<!DOCTYPE article PUBLIC "-//NLM//DTD JATS (Z39.96) Journal Archiving and Interchange DTD v1.0 20120330//EN" "JATS-archivearticle1.dtd">
<article xmlns:xlink="http://www.w3.org/1999/xlink">
  <front>
    <journal-meta />
    <article-meta>
      <contrib-group>
        <aff id="aff0">
          <label>0</label>
          <institution>Ole Kallehave, Mikael B. Skov, Nino Tiainen HCI Lab, Department of Computer Science, Aalborg University Selma Lagerlöfs Vej 300</institution>
          ,
          <addr-line>9220 Aalborg East</addr-line>
          ,
          <country country="DK">Denmark</country>
        </aff>
      </contrib-group>
      <pub-date>
        <year>2010</year>
      </pub-date>
      <abstract>
        <p>"#$#%&amp;!'($&amp;%)*$+,(!-&amp;*.(,/,0+&amp;1!2)3! 4,56#$&amp;%!7*+&amp;(*&amp;8!79)(1&amp;)!:(+;&amp;%1+$&lt;! 79)(1&amp;)8!:=8!7&gt;?!@AA! B6C&amp;1/)53,/*.+)%8!5C/C9+/1,(DE19)(1&amp;)C)*C#F! ! .*7"I*&amp;A;4"</p>
      </abstract>
      <kwd-group>
        <kwd>G)H&amp;+%)!'($&amp;%)*$+</kwd>
        <kwd>&amp;!-&amp;*</kwd>
        <kwd>(</kwd>
        <kwd>/</kwd>
        <kwd>0+&amp;1!'(1$+$#$&amp;!</kwd>
        <kwd>(+</kwd>
        <kwd>&amp;%1+H)H&amp;!H)!G)H&amp;+%)! 4)56#1!</kwd>
        <kwd>(+</kwd>
        <kwd>&amp;%1+$I%+</kwd>
        <kwd>!H)!A&amp;($&amp;)H)! "#(*</kwd>
        <kwd>)/8!JKKKLMJK8!A</kwd>
        <kwd>%$#0)/! +)(E#5)C6$! ! !7?7="J</kwd>
        <kwd>4"</kwd>
      </kwd-group>
    </article-meta>
  </front>
  <body>
    <sec id="sec-1">
      <title>-</title>
      <p>"#$%&amp;'()*!+,!
&gt;*%?'*"@'A*BC$A8(?*%"D"3*E"FG"H?A'$7"
@/$-.3A3$4:%
9+E'&amp;05$-+G01&amp;#6%
:+(186%
9$:3#-%!$4:+":3;$%($?)-151#6%
9&amp;#$-KE#4$I116%
G"-"#$,$-.%1A%K3215"4%93:14/$4%
=+C'&amp;1.+$9+'DE$+#($!+/"C$%+'('+F6%
7+/.1K6$
!"##$%&amp;'(')'*"+,-.'
!"#$%&amp;%%'%% ()$%*+#,$-.$/%0)1223-#%(4155$67%*-%*,83$-.%93:25"6%(1%!41;3/$%
0)122$4:%&lt;3.)%=1-'&gt;8;31+:%!41/+?.%@-A14,".31-%
!"#$%&amp;'()$*+&amp;,+$-+.#&amp;/+&amp;01$+#($2,"##1$3"41'56$
!"#$%B%'%% !$4:+":31-%@-'03.+7%0)1223-#%A14%C$"5.)6%D11/%3-%0+2$4,"4E$.:%</p>
      <p>7.1$-+..18+,1)$9&amp;/+1.$%6$:/",$+#($;&amp;#"$&lt;&amp;+&amp;#1#6%
!"#$%FF%'%% (1&lt;"4/:%"%G1835$%*2253?".31-%.1%H4$".$%0$/$-."46%*&lt;"4$-$::%</p>
      <p>=&amp;&gt;5$=1.1&amp;&gt;#51)$?+'0$*+#$@+.01'1#$+#($!+#$A&amp;1/8"BB6%
!"#$%FI%'% G&gt;=*JH*7%*%!$4:+":3;$%!$4:1-"5%G1-3.143-#%06:.$,%.1%0+2214.%
%
%
%
%
%
%
%
$
%
%
!"##$%&amp;'/')'0-.$1#'
!"#$%FL%'% K+35/3-#%!$4:+":31-%!41A35$:%3-%.)$%M35/7%N:3-#%G1835$%9$;3?$:%":%
!"#$%O&amp;%'%% =+/#3-#%N:$4:%(1&lt;"4/:%!43;"?6%1-%G1835$%9$;3?$:%
31C1DD+$%+.1C+/")$H1('"$I1"#)$@+J&amp;F$?.FE8&amp;F1(&amp;)$H+0'&amp;D/$-1..1K)$
!"#+08+#$9E4+#)$?.155+#('"$?DLE&amp;50&amp;)$I"''&amp;1$M'+#"'$+#($;"'F+#$
!"#$%OB%'%% D41,%P.)3?:%.1%Q"5+$:%3-%.)$%9$:3#-%1A%G1835$%!@=H%</p>
      <p>!+#10$A+,&amp;5R%
!"#$%&amp;F%'%% &gt;2214.+-3.3$:%"-/%H)"55$-#$:%3-%G3-3-#%K$)";314"5%P?1-1,3?:%.1%
!"##$%&amp;'2')'0&amp;"345'
!"#$%&amp;I%'%% S".)$43-#%"-/%!4$:$-.3-#%01?3"5%D$$/8"?E%.1%H)"-#$%91,$:.3?%</p>
      <p>P5$?.43?3.6%H1-:+,2.31-%
9+0081N$:0E(.1K)$:&amp;F"#$M8+FC1'5)$3E08$3100&amp;1$+#($-1,&amp;#$%E'D81..6%
!"#$%&amp;L%'%% (1&lt;"4/:%P#1?$-.43?%D+$5%PAA3?3$-?6%D$$/8"?E%</p>
      <p>&lt;&amp;+4"$M+F+D8")$O&amp;.&amp;G1$PE&amp;#0+.)$9&amp;D81..1$:D"00)$*+55&amp;.&amp;5$-"50+/"5$+#($Q+#$
!"#$%T&amp;%'%% H4$".3-#%UH115V%G1835$%($?)-151#3$:%(1%J$/+?$%($$-%P-$4#6%N:$%</p>
      <p>A+#&amp;1.$O&amp;00"#)$!+#10$31+()$3E551..$%1+.1)$%1#$M"N+#$+#($2E/+#4$=E"6$
!"#$%TB%'%% =+/#3-#%!$125$%".%M14E%"-/%&gt;.)$4%()34/'!"4.6%W1?".31-:R%</p>
      <p>9+R$I6$S&amp;.5"#)$A1'1/$O"501')$:8+E#$I+N5"#$+#($:&amp;F"#$T((&amp;5"#%
The Augmented Shopping Trolley: An Ambient Display To
Provide Shoppers with Non-Obvious Product Information
Jon Bird, Vaiva Kalnikaité and Yvonne Rogers</p>
      <p>Pervasive Interaction Lab</p>
      <p>The Open University</p>
      <p>Milton Keynes, MK7 6AA, UK
{j.bird, y.rogers}@open.ac.uk, vaivak@gmail.com
ABSTRACT
The Augmented Shopping Trolley consists of an ambient
handlebar display connected to a scanner. When a shopper
scans an item the handlebar lights up to provide them with
information about the product, such as its nutritional,
ethical or environmental attributes, that are not obvious
from its packaging or label. The system is designed to
seamlessly integrate with a shopping experience: it uses
familiar supermarket technologies; it keeps both of a
shopper’s hands free; and the simple ambient display
facilitates the ‘fast and frugal’ decision-making typically
observed in a supermarket. Our initial lab-based study
shows that the display can be understood at a glance and
used to select items based on a product’s nominal properties
(for example, it is organic), ordinal properties (for example,
it has low, medium or high food miles), as well as a
combination of the two at the same time. Where as usability
was the focus of our initial design, ethical issues have come
to the fore as we develop the system for use in
supermarkets and we discuss how these are influencing our
design.</p>
      <p>Author Keywords
Persuasive technologies,
product information, ethics.</p>
      <p>ambient
display,</p>
      <p>shopping,
ACM Classification Keywords
H5.m. Information interfaces and presentation (e.g., HCI):
Miscellaneous.</p>
      <p>INTRODUCTION
In a supermarket, shoppers tend to make snap judgments
based on just a few salient cues (low price, recognized
brand and attractive packaging) and they rarely take time to
read product information labels [7]. However, recent
consumer surveys indicate that shoppers want more
Permission to make digital or hard copies of all or part of this work for
personal or classroom use is granted without fee provided that copies are
not made or distributed for profit or commercial advantage and that copies
bear this notice and the full citation on the first page. To copy otherwise,
or republish, to post on servers or to redistribute to lists, requires prior
specific permission and/or a fee.</p>
      <p>Copyright © 2011 for the individual papers by the papers' authors.</p>
      <p>
        Copying permitted only for private and academic purposes. This volume
is published and copyrighted by the editors of PINC2011..
information about the global consequences of their
consumer decisions [
        <xref ref-type="bibr" rid="ref2">2</xref>
        ]. Our goal is to provide
‘nonobvious’ nutritional, ethical and environmental product
information, that is, information that is not immediately
obvious from an item’s packaging or label, in a form that is
as salient as the features that typically inform consumers’
decision making. The Augmented Shopping Trolley (Figure
1) is designed so that it fits as seamlessly as possible into a
supermarket shopping experience. We use familiar
supermarket technologies: augmenting a standard shopping
trolley by attaching a scanner and embedding an ambient
display in the handlebar. This gives our system two
advantages over using mobile devices to provide product
information. First, the trolley scanning technology is faster
[4] and second, because the ambient display is built into the
trolley handlebar a customer’s shopping experience is not
disrupted by having to repeatedly access and store a mobile
display. Underhill [10, see chapter 4] emphasizes the
importance of having both hands free during shopping.
Our approach to designing an effective ambient display,
first outlined in [9], is motivated by studies of ecological
rationality which investigate how people make reasonable
decisions given the constraints of limited time, information
and computational resources that characterize most real
world situations [6, 8]. This research indicates that most
natural decision making is made on the basis of ‘fast and
frugal’ heuristics – short-cut strategies where people ignore
most of the available data and instead focus on the most
useful information and process it quickly. Often people
make a decision based on a single reason as this strategy is
quick and simple and avoids having to weigh up trade-offs
between multiple and potentially conflicting options. This
approach is not rational in certain environments, namely,
those where available pieces of information are
approximately equally useful. However, in a shopping
environment, the distribution of information usefulness is
highly skewed, that is, the most useful piece of information
is a lot more important than the second most useful, which
in turn is considerably more important than the third, etc.
      </p>
      <p>Our handlebar ambient display consists of just sixteen
LEDs. When a shopper scans a product, a few pieces of
non-obvious information, such as whether it contains nuts,
is fair trade or has low food miles, are displayed as a salient
pattern on the display.</p>
      <p>Given that information salience influences a person’s
behaviour unconsciously [1], rather than through rational
reflection, this raises ethical concerns about the Augmented
Shopping Trolley, chief of which is that this system could
potentially manipulate people into behaving in ways that
they would not otherwise do, and furthermore, that they
might not be aware that they had been manipulated. This
concern, and also issues to do with privacy and clarifying
how our system benefits shoppers, form the ethical
considerations that are influencing how we deploy the
Augmented Shopping Trolley in a supermarket.</p>
      <p>The paper is structured as follows: first, we describe the
display hardware and how it conveys product information;
second, we describe a lab-based evaluation of the system
that demonstrates the efficacy of the ambient handlebar
display for conveying non-obvious product information;
and third, we describe the ethical issues that are informing
the development of the system for use in supermarkets.</p>
      <p>AMBIENT HANDLEBAR DISPLAY DESIGN
The handlebar display was designed to provide shoppers
with salient and easy to read information about a scanned
product’s nominal properties (for example, whether it is
organic or contains nuts), its ordinal properties (for
example, if it has low, medium or high food miles), as well
as a combination of the two at the same time. We
constructed the display by attaching 16 bicolour LED units
to a piece of wood inside a transparent plastic tube (Figure
1). This replaced the plastic handlebar in a standard
shopping trolley. The LEDs are controlled using 2
TLC5940 chips (Texas Instruments) that are driven by an
Arduino microcontroller. In our lab-based study this is
attached via a USB cable to a laptop running a Processing
application. Each LED unit can be set to red, green or
orange (when both the green and red LEDs are on). Each
time a product is scanned, the display changes in the
following way. First, it goes from an all green background
(idle state) to a half second sweeping movement of orange
that indicates scanning is in progress. There is then a beep,
as typically heard at a checkout counter, to signal that
scanning is completed and the display then changes to a
new state that provides relevant information about the
product. If the display is configured to show a nominal
property of the product, then it flashes green if the property
is present and shows the idle state if it is not. If the display
is providing ordinal information about the product, the
display employs a bar graph metaphor, with the number of
red pixels indicating the degree to which an item has a
property. Specifically, if an item has a low degree of a
property then pixels 1-3 turn red and 4-16 turn green; if
medium then pixels 1-8 turn red and pixels 9-16 turn green;
and pixels 1–13 turn red and 14-16 turn green if the item
has a high degree of a particular property. Finally, both
these representations can be combined to show the value of
a nominal and an ordinal property at the same time. In our
study, after a participant selected or discarded an item, the
display changed back to the all green idle state.</p>
      <p>LAB-BASED SYSTEM EVALUATION
5 adults (1 female, 4 male, aged between 20 and 40) took
part in a lab-based evaluation of the Augmented Shopping
Trolley. Each participant completed 12 shopping scenarios
where they were asked to pick up and scan 5 items of a
particular product type and only select those items that met
specified criteria. A scanner was attached to the shopping
trolley (Figure 1) but was non-functional and the handlebar
display was changed using a Wizard of Oz methodology.</p>
      <p>On the basis of the changes in the patterns on the handlebar
display, participants had to decide whether to select the
item and place it in their trolley or discard it and place it on
an adjacent table. Since this was an exploratory study, we
were intentionally vague about the operation of the ambient
display as we wanted to see whether participants could
understand it intuitively. We only told participants that the
display patterns would change depending on whether a
product had a specific property (yes/no), the degree to
which a product had some property (high/medium/low) or a
combination of the two. Participants were allowed to scan
the items as many times as they wanted and in any order,
before they made their decision about whether to select a
particular item. We used 4 product types: milk; breakfast
cereal; wine; and juice. Each shopping scenario used one of
the product types and participants were asked to select from
5 different items. For example, select those bottles of wines
that meet the specified criterion (fair trade) and put them in
the trolley, and place the others on the discarded items
table. Each of the items was a real product but we masked
any product information on the packaging and told
participants to only use the handlebar display to decide
whether they should select an item or not. The experimenter
playing the Wizard of Oz role sat at a table on which the 20
shopping items were grouped by product type. Each item
was individually numbered so that the experimenter could
change the display appropriately when the participants
scanned a particular item.</p>
      <p>In the first 4 shopping scenarios the handlebar display
indicated whether a scanned item had a particular nominal
property or not: whether a milk product was organic;
whether a breakfast cereal contained nuts; whether a bottle
of wine was fair trade; and whether a carton of juice
contained added sugar. In 2 of these scenarios the
participants had to select items that had a particular
property and in the other half they had to discard items if
they had a particular property. For example, in the first
shopping scenario participants had to select a milk product
if it was organic and discard it if it was non-organic; in the
second shopping scenario participants had to select a
breakfast cereal if it did not contain nuts and discard it if it
did.</p>
      <p>In the next stage of the evaluation, the participants
completed 4 shopping scenarios where the display indicated
whether a product contained a low, medium or high value
of a particular ordinal property. The task was to select items
that had a specified property to a particular degree.</p>
      <p>Specifically, participants were asked to select milk with a
medium fat content, cereals with a high sugar content, wine
with low food miles and juice with a medium water content.</p>
      <p>In none of these scenarios were participants asked to
discard items if they had properties of a particular degree.</p>
      <p>The final 4 shopping scenarios tested whether participants
could understand the display when it simultaneously
showed information about both a nominal and an ordinal
property of a scanned item. Participants were asked to
select milk that was organic and low fat, cereals that
contained nuts and had a medium sugar content, juice that
had added sugar and high water content and wine that was
not fair trade and had medium food miles. Only in the wine
scenario did participants have to reject items on the basis of
information about a nominal property of the product.</p>
      <p>USABILITY RESULTS
4 out of the 5 participants were able to interpret the ambient
handlebar display and complete all the tasks without any
mistakes. The other participant made one consistent error in
2 of the first shopping scenarios where the task was to
discard items if they had a particular nominal property: they
selected, rather than discarded, them, but did not repeat this
error in the final shopping scenario which also required an
item to be discarded if it had a particular nominal property.</p>
      <p>Several participants reported that they found the tasks
where they had to discard items with particular properties
more difficult and it did seem to increase the cognitive load
in all participants, resulting in a slightly slower response
time (approximately 2 seconds, rather than 1 second for the
other conditions). This could be due to the colours used in
the display: a nominal property is indicated by a green
blinking display, a colour that many people associate with
positive properties, rather than ones that should be avoided.</p>
      <p>All participants reported that the display was intuitive to
use and were able to quickly read it even though they were
not given explicit information on the meaning of the display
patterns. Only two participants scanned items more than
once and this was exploratory activity at the beginning of
the evaluation when they were seeing how the interface
worked.</p>
      <p>ETHICAL ISSUES AND FURTHER DEVELOPMENT
Whereas usability issues informed our initial design, ethical
considerations are shaping the development of the
Augmented Shopping Trolley for use in supermarkets. This
is because our ambient display not only provides salient
product information for shoppers, but also potentially
influences what they purchase. The use of persuasive
technologies raises ethical concerns for many people. For
example, Page and Kray [3] used an online questionnaire to
investigate people’s views on the ethics of using persuasive
technologies to encourage healthy living. 72 participants
rated the ethical acceptability of a number of different
scenarios which varied in 3 different factors: whether a
participant chose to use the technology or an external
agency initiated its use; whether there was a clear benefit
for the participant or not; and the technology used (text
messages to the participant’s mobile phone; public
announcements in the participant’s location; Facebook
messages; restrictions on the participant’s bank account;
and electric shocks). The results indicated that the majority
of the participants viewed the use of persuasive
technologies in most of the questionnaire scenarios as
unethical. When there was no clear benefit to the
participant, mobile phone were considered the most ethical
persuasive technology. However, approximately the same
proportion of participants (40%) considered them very
ethical or ethical as the proportion that considered very
unethical or unethical when. A large majority of
participants found the other technologies very unethical or
unethical. In scenarios where the use of a technology would
clearly benefit the participant, for example, save their life,
then this usage was considered slightly more ethical than
the cases where the technology did not benefit the
participant. However, it is not clear whether these
differences were statistically significant. When people were
able to freely choose whether to use a persuasive
technology or not, then texts, public announcements and
Facebook messages were considered ethical by the majority
of respondents, in comparison to the situation where the use
of the persuasive technology was initiated by an external
entity (for example, the UK’s National Health Service).</p>
      <p>Electric shocks and bank account restrictions were
considered very unethical or unethical by the majority of
respondents, even when a participant chose to use them.</p>
      <p>Page and Kray’s findings seem to concur with a central
factor identified by applied philosophical analyses of
ethical behaviour, for example, the use of persuasion in
advertising [5]. Namely, the ethics of an action are
determined, to a large degree, by the extent to which that
action impacts on an individual’s autonomy, that is, their
capacity to choose how to act and determine their own life.</p>
      <p>Page and Kray’s research also highlights that privacy and
the extent to which a participant benefits are important
issues for determining the ethical acceptability of
persuasive technologies. All three of these ethical
considerations (autonomy, privacy and benefits) are
shaping the development of the Augmented Shopping
Trolley.</p>
      <p>To ensure shopper’s autonomy, they will be free to decide
whether they use the Augmented Shopping Trolley and also
able to choose which particular non-obvious product
information they want to be informed about. Given that
users can configure the system to provide different product
information, privacy is not compromised, even though the
handlebar will be visible to other shoppers, as they will not
understand what particular LED patterns mean. Some of the
product information that will be provided by the
Augmented Shopping Trolley can clearly benefit a
participant, for example, nutritional data, whereas other
information, such as food miles, may not have direct
personal benefits. In fact, trying to minimize food miles
may lead, literally, to a personal cost. However, we assume
that if participants choose to be informed about a particular
type of product information then they do so because it is of
benefit to them and in keeping with their lifestyle choices.</p>
      <p>We are currently considering how to use the display to
provide aggregate information about the contents of a
participant’s trolley. The display could indicate how
averaged values of all the participant’s purchases relate to
some norm(s), for example, is the weekly shop below or
above the average shopper’s food miles. Clearly, there are
normalization issues to be resolved to enable such
comparisons to be made. One ethical consideration with
this type of display is that even if an observer did not know
what aspect of product information the aggregate display
encoded, under certain conditions it could be evident
whether a participant was above or below a norm, thereby
compromising a shopper’s privacy. For example, if the
observer had also used the display themselves and the
colour encoding was fixed. One way to ensure privacy is to
allow participants to customize aspects of the display, such
as the colour encoding used. A second ethical concern with
this sort of display is that norms, like salience, typically
influence people unconsciously. To ensure that the
autonomy of participants is not compromised it seems
important to inform them about the methods used in a
display and how these typically influence behaviour before
they choose to use the Augmented Shopping Trolley
CONCLUSIONS
Our lab-based study shows that participants can rapidly
read a shopping trolley handlebar display to determine both
nominal and ordinal properties of a scanned product. Our
display is intuitive to use and requires no training.</p>
      <p>Participants find it easier to select items when they have
desirable properties than to not select them because they
have undesirable properties. The Augmented Shopping
Trolley makes non-obvious nutritional, ethical and
environmental product information salient to shoppers and
facilitates the fast and frugal decision making typically used
in a supermarket. Some of the global consequences of
selecting particular products can now be made salient to
shoppers at the point of decision making, potentially
facilitating changes in consumer behaviour. We argue that
our system is an ethical persuasive technology as it
enhances the ability of shoppers to buy choose products in
accordance with their individual values.</p>
      <p>Persuasion In-Situ:
Shopping for Healthy Food in Supermarkets
ABSTRACT
Healthy lifestyle is a strong trend at the moment, but at the
same time a fast growing number of people are becoming
over-weight. Persuasive technologies hold promising
opportunities to change our lifestyles. In this paper, we
introduce a persuasive shopping trolley that integrates two
tools of persuasiveness namely reduction and suggestion.</p>
      <p>The trolley supports shoppers in assessing the nutrition
level for supermarket products and provides suggestions for
other products to buy. A field trial showed that the
persuasive trolley affected the behaviour of some shoppers
especially on reduction where shoppers tried to understand
how healthy food products are. On the hand, the suggestion
part of the system was less successful as our participants
made complex decisions when selecting food.</p>
      <p>Author Keywords
Shopping, health, persuasive, supermarkets.</p>
      <p>ACM Classification Keywords
H5.m. Information interfaces and presentation (e.g., HCI):
Miscellaneous.</p>
      <p>INTRODUCTION
Healthy lifestyles is a hot topic in most Western societies as
a rapid growing number of citizens are either over-weight
or obese, e.g. more than 50% of the adult population in
Denmark are either over-weight or obese [9]. Over-weight
problems come from several circumstances, e.g. the lack of
exercise or unhealthy food, but in general people buy and
consume food that contains a lot of sugar or fat. Thus, we
need to alter people’s behaviour and attitude while they
shop groceries and other food products in supermarkets.</p>
      <p>When supermarket shopping, more studies have shown that
consumer behaviour is highly controlled by routine and is
not simply changed or altered [8]. In fact, even if shoppers
want to change their shopping behaviour and patterns, they
find it difficult to understand the nutritious values of many
Copyright © 2011 for the individual papers by the papers'
authors. Copying permitted only for private and academic
purposes. This volume is published and copyrighted by the
editors of PINC2011
products, e.g. they cannot understand nutrition labels or
how much sugar or fat the product contains [5]. Further,
one of the fundamental problems resides in the fact that we
are confronted with an overwhelming number of different
food products and it is often difficult to identify and choose
the more healthy ones. Iyengar and Lepper showed in an
experimental study that consumers were more satisfied
with their own selections when they have fewer options to
select from [5]. Schwartz refers to this as the paradox of
choice claiming that the huge number of choices decreases
people’s real choice and decision-making [10]. Thus,
people are likely to continue their current routine type of
behaviour (as illustrated by Park et al. [8]) and this could
potentially prevent them from making healthier choices.</p>
      <p>
        Emerging technologies are increasingly being used to alter
people’s opinions or behaviour, e.g. smoking cessation [4]
or promoting sustainable food choices [7]. Fogg refers to
such technologies as persuasive technologies or captology
[3]. Fogg states that contemporary computer technologies
are currently taking on roles as persuaders including
classical roles of influence that traditionally were filled by
doctors, teachers, or coaches [3]. Research studies within
different disciplines are increasingly concerned with such
persuasive technologies that may be used to create or
change human thought and behaviour. As examples, Chang
et al. [
        <xref ref-type="bibr" rid="ref2">2</xref>
        ] propose the Playful Toothbrush that assists parents
and teachers to motivate young children to learn thorough
tooth brushing skills while Arroyo et al. [1] introduce the
Waterbot that motivates behaviour at the sink for increased
safety. Both these examples propose rather simple, yet
potentially powerful input and feedback that aim to inform
users of their own behaviour.
      </p>
      <p>Todd et al. [11] illustrate theoretically how nudging could
persuade shoppers to select healthy food products based on
simplified information to the shoppers in-situ, but call for
empirical understandings of persuasive shopping. We
propose a persuasive shopping trolley application called
iCART that attempts to motivate change towards more
healthy shopping behaviour. First, we outline the idea
behind the design of the trolley application and then reports
from field studies of use on its effects on behaviour change.
iCART: INFLUENCING SHOPPING BEHAVIOUR IN-SITU
iCART is a persuasive application mounted on a shopping
trolley that attempts to persuade the shopper’s behaviour
and awareness. The system was implemented in C# using
Windows Presentation Foundation for the interface and a
Microsoft SQL server.</p>
      <p>From our previous research [6], we learned that many
consumers actually attempt to buy healthy products when
supermarket shopping, but often they would find it difficult
to assess the nutrition value or energy level. In fact, several
consumers are actually unsure what a healthy food product
is. Shoppers find it difficult to understand the nutrition
information labels on the food products and they usually
don’t bother consulting this information. Supermarket
products and groceries are rather diverse, e.g. ranging from
simple non-processed products (e.g. an apple) to more
complex processed products (e.g. a pizza). Usually people
find it difficult to assess how healthy processed products
are. Furthermore, people find it difficult to change behavior
and usually choose well-known products while shopping.</p>
      <p>The overall idea of iCART is that all food products and
items in a supermarket can be classified according to
nutrition level and this classification will be presented to
the user of the trolley every time the shopper puts an item
into the trolley. For our persuasive system, we adapt the
nutrition label initiative called Eat Most from the Danish
Veterinary and Food Administration. For our purpose, it
provides a simple classification of food products based on
the nutrition values of a product. The classification label
includes a table for calculating the value of all food
products. According to the label, all products can be
classified as Eat Most, Eat Less, or Eat Least.</p>
      <p>The typical use situation could be as follows (illustrated in
figure 1): The user walks around the supermarket with the
trolley, chooses food products and places them in the
trolley (a), the trolley recognizes the product and displays
its classification according to the Eat Most label (b), and
the system updates the status for the entire trolley on
numbers of Eat Most, Less, and Least food products (c).</p>
      <p>(a) (b) (c)</p>
      <p>Figure 1: Illustrating the process of using iCART
Interaction Design
We adapted three persuasive design tool principles from
Fogg namely reduction and suggestion [1]. The persuasive
shopping trolley should 1) present or visualize product
nutrition in a simple way and 2) present alternatives to less
healthy products. Finally, we decided that the system
should be a walk-up-and-use system on a shopping trolley.</p>
      <p>Reduction reduces complex behaviour to simple tasks in
order to increase the benefit/cost ratio and thereby
influence the user to perform the behaviour [3]. As stated
above, consumers find it difficult to assess the overall
nutrition level for products. The persuasive trolley reduces
this nutrition value assessment through the simplification in
the Eat Most classification and thereby the assessment now
becomes a simple task. This is illustrated in figure 2 where
different products have been classified, e.g. milk as eat less
(middle picture).
We colour-coded the three categories with green, yellow,
and red. Figure 3 shows the classification for a cereal
product called Havrefras and this product is an eat least
product. The implementation in iCART reduces the action
of assessing the nutrition value of a product by providing a
simple classification of only three categories.</p>
      <p>Suggestion means that persuasive technologies have greater
power if they offer suggestions at opportune moments [3].</p>
      <p>Consumers find it difficult to choice healthier alternatives
as they often have limited understanding of the relative
levels of nutrition between more products. The persuasive
trolley offers suggestions for alternative products (Eat
Most) within the same product group when the shopper
choices an Eat Less or Eat Least product in the trolley. We
consider this an opportune moment as the shopper often
will find the alternatives in their present supermarket area
(as illustrated in figure 4 where two alternative cereals are
suggested for the cereal in figure 3).</p>
      <p>FIELD TRIALS
We conducted field trials with the shopping trolley at the
local supermarket called føtex. It was rather important to us
to understand the use of the system in-situ to facilitate the
whole shopping experience.
11 shoppers were recruited through public announcements
and we required that they shopped for food products on a
regular basis. The shoppers were between 27 and 58 years
old and represented different kinds of households and
worked in diverse job professions. We asked them to fill in
a questionnaire on their supermarket shopping experiences
prior to the trials. Some of the participants were highly
concerned with nutritious food while others were less
concerned. The participants were divided into two groups
one group used iCART while the other group served as a
control group using a regular shopping trolley. We
balanced them in the two groups based on their
selfreported knowledge and attitudes towards nutritious food.</p>
      <p>Before the trials, we carried out a pilot test to verify and
adjust the process and our instructions. Participants were
not informed about the purpose of the study in order to
minimize study impact and iCART participants were told
about the system but not its focus on healthy food products.</p>
      <p>The trials consisted of a three parts namely an introduction,
the actual shopping, and a debriefing. We instructed the
participants to shop items from a pre-generated shopping
list using their own normal criteria for food selection. Thus,
they should try to shop as they normally would. The
shopping list contained 12 items, e.g. milk, cheese, pate.</p>
      <p>The list included only general product groups (except for
one item) leaving the participants to choose within the
group, e.g. cheese where they could choose more 20
different cheese products. They were free to choose in
which order they would collect the items.
303 food items were entered into a SQL database
representing all items in the store within the groups from
the shopping list. Data collection was done through 1) a
trolley-mounted video camera that captured verbal
comments and shopping behaviour and 2) the system
logged and time stamped all user interactions enabling to
reproduce action sequences afterwards. The sessions were
done during normal trading hours and they were not
required to check out the collected items.</p>
      <p>We evaluated iCART as a Wizard of Oz experiment where
one of the authors acted as wizard implementing the actions
taken by the participant. When a food product was put into
the trolley, the wizard would update this information in the
system. Another person observed the participant while
shopping in order to facilitate the following interview. The
same procedure was used for the control group, but without
the trolley-mounted display. The total time spent ranged
from 12:08 to 40:28 minutes. Finally, a debriefing session
including questionnaires and semi-structured interview was
conducted immediately afterwards, e.g. they were asked to
assess their own session and the collected items.</p>
      <p>OBSERVATIONS AND DISCUSSION
The five participants using iCART expressed that they
liked the system and they would possibly use it if available
in supermarkets. While food products in supermarkets
already have different labels for determining the health or
nutritious level, iCART became a personal technology that
guided the shopper while shopping. This also had the
advantage that shoppers always knew where to look for the
nutritious information for all products. Today, this
information is located on the packaging of the product and
thereby distributed in the store.</p>
      <p>The reduction element of iCART was quite successful. Out
of the 60 food products selected by the participants using
the system, 30 were classified as Eat Less or Eat Least.</p>
      <p>Thus, half of the selected products were less healthy. In
several cases, the participants were surprised to realize that
a certain product was less healthy. For example, one of the
participants chose a bag of carrot buns and got surprised to
see that these buns were Eat Least: “I thought they were
healthy as they contain carrots”.</p>
      <p>On the other hand, several shoppers chose less healthy food
products and were aware of it – even without the help from
iCART. But the classification made them reflect upon their
choices and several of them started talking about nutrition
and healthy food. One participant said: “But the Eat-Least
classification makes you think and questions whether you
have made the right choice”. From our analysis, it seemed
that they acted out of routine behaviour and that they
partially knew the consequences of these choices. This
confirms the findings by Park et al. [8] on changing
shopping routine behaviour. In summary, the reduction
element of iCART was quite successful as it raised the
awareness of the shoppers on the nutritious level of the
chosen products.</p>
      <p>The suggestion component of iCART was less successful
compared to the reduction. The participants changed their
choices 3 times out of 30 (10%). This low number was
somewhat surprising, but shoppers gave several reasons for
this. Some would not change their choice, as they would
rather buy an unhealthy food product that was biodynamic
than buy a healthy product that was not. So the shoppers
would implement their own classification schemes based
on other aspects than nutrition. Also, some shoppers stated
that they never bought any light or zero products, which
often were the products suggested by our system. They said
that they would rather eat less of the unhealthy products
than buy a light product.</p>
      <p>During the field trials, 18 times did the shoppers take a look
at the suggestions made by iCART, but in most situations
(14 times) they chose not to follow the suggestion. This
indicates that the shoppers are interested in receiving
suggestions but the actual suggestions made by the system
in the situation were not good enough. As illustrated above,
they had different objectives when shopping and perhaps
suggestion functionality should be carefully organized.</p>
      <p>We identified an interesting observation concerning trust to
the system. Some users expressed scepticism towards the
suggestion part of the system while none of them really
questioned the reduction part. Most of them stated that
nutrition labelling whether on the actual product or
implemented in an interactive system on the trolley should
be controlled and accredited by public authorities. They
were more critical when it concerned suggestions than
reductions. The problem with suggestion could reside in
that it could feel like ads or commercials for other products.</p>
      <p>That could be a potential problem when implementing
suggestion tools. However, as expressed by one of the
female participants: “It is cool to be guide. I don’t mind
help or receive suggestions, I’m a grown-up who can make
my own decisions”. This could imply that to change
behaviour designers should focus on providing reduction in
complexity of assessing the food product, but they should
perhaps not suggest or give recommendations to the user.</p>
      <p>Shopping in supermarkets is noisy and complex and it can
be stressing due to several multimodal inputs. We noticed
how several participants missed reductions or suggestions
on the screen while acting in the environment. Thus, they
would actually not receive the information proposed by the
system. Also, one participant stated that shopping is private
even though it takes place in a public environment.</p>
      <p>The participants who shopped without the persuasive
guidance appeared to have fewer reflections on nutrition
and health. In fact, the iCART participants eventually
bought 25 food items classified as Eat Least whereas the
other participants bought 34 Eat Least products. The
difference cannot only be explained in terms of the
suggestion tool implemented in iCART, but the interaction
made them reflect.</p>
      <p>CONCLUSION
We presented the persuasive shopping trolley iCART that
guides supermarket shoppers in choosing more healthy
food products by classifying all products in three groups
namely Eat More, Eat Less, and Eat Least. Field trials with
11 shoppers showed that iCART proved to provide good
input on reduction, e.g. reducing the complex task of
assessing whether a product is healthy or less healthy. Our
participants noticed when the system classified a product as
Eat Least and usually they would start reflecting upon this.</p>
      <p>Only a few times did this result in change of behaviour
where the user changed the original choice. But mostly the
suggestion part of the system was less successful. This was
mainly due to the fact that several participants had rather
specific requirements to their products, e.g. they should be
biodynamic or they never bought light-products.</p>
      <p>Based on our findings, we see a number of future research
avenues. First, rather than optimizing the algorithms behind
suggestion tools, we propose that we should design systems
that enables shoppers to make their own decisions in-situ.</p>
      <p>This could require a different approach to reduction. Also,
we need to understand the long-term effects of such
systems and we plan to conduct more longitudinal studies.</p>
      <p>ACKNOWLEDGMENTS
We would like to thank the shoppers from the field trial as
well as reviewer comments on earlier versions of the paper.
Towards a Mobile Application to Create Sedentary</p>
      <p>Awareness
Gijs Geleijnse, Aart van Halteren and Jan Diekhoff</p>
      <p>Philips Research</p>
      <p>Eindhoven, The Netherlands
gijs.geleijnse@philips.com , aart.van.halteren@philips.com
ABSTRACT
Prolonged sitting time is a potential health risk, not only for
people with an inactive lifestyle, but also for those who do
meet the recommended amount of physical activity. In this
paper, we evaluate SitCoach, a mobile application to nudge
people from their seats. The application is targeted to office
workers. SitCoach monitors physical activity and sedentary
behavior to provide timely feedback by means of
suggesting sitting breaks. A pilot experiment with a group
of 8 users learned that the general awareness of the
importance of sitting breaks is low. Combined with the
belief that the ability to take sitting breaks is highly
dependent on external factors, a strategy of proposing break
reminders may not be the most successful for this target
group. Future work should focus on raising awareness of
the problem and providing insights into personal sitting
behavior.</p>
      <p>Author Keywords
Sitting time, mobile persuasion, sedentary awareness,
physical activity.</p>
      <p>ACM Classification Keywords
H5.m. Information interfaces and presentation (e.g., HCI):
Miscellaneous.</p>
      <p>INTRODUCTION
In the past years, a substantial amount of research has been
devoted to physical activity promotion through mobile
devices. Using the accelerometer embedded in a mobile
phone or in a dedicated device, the energy expenditure of
the user can be estimated. The user may receive feedback
on his past physical activity level in minutes or burned
calories.</p>
      <p>
        Several strategies have been explored to influence the
UHVX¶EDKLRYGQWHSUPLJKFDOV\WYH
Most notably, the usage of virtual rewards [
        <xref ref-type="bibr" rid="ref2">1,2</xref>
        ], social
support [3,9] and goal setting [8] have shown to be
Copyright © 2011 for the individual papers by the papers' authors.
      </p>
      <p>Copying permitted only for private and academic purposes. This volume
is published and copyrighted by the editors of PINC2011."
successful persuasive strategies to establish an increased
amount of physical activity.</p>
      <p>Recent medical literature reports that not only an inactive
lifestyle may lead to adverse health effects, but also
sedentary behavior itself is harmful. Prolonged sitting time
is also dangerous for people who meet the WHO guidelines
of 30 minutes of physical activity per day [4,12]. The
reduction of sedentary behavior is hence identified as a
target behavior that contributes to a healthy lifestyle.</p>
      <p>S6XRUW RW FUHDW UHVQDZ RI H¶RVQ HGVQWDU\ EDHKLRUY
may be beneficial. However, as Owen et al. state in [12],
HLY³JQ HWK UWHFQ LUHFQRWJ RI WLKV HSKRQP RI WR
much sitting, there are not yet any recommended clinical
guidelines. Commonsense might suggest that it may be
prudent to try to minimize prolonged sitting with 5 minute
In this paper, we describe SitCoach, a mobile application
that assists the user to create sedentary awareness and to
have regular sitting breaks. Such an application can be
combined with additional physical activity promotion
features. To the best of our knowledge, SitCoach is the first
prototype mobile application aimed to reduce sitting time.</p>
      <p>Using SitCoach, the goal is to collect insights into
SLEHROWV RW HLIOXFQ SHRVO¶ LVWJQ EDHKLRUY XLVJQ D
mobile device.</p>
      <p>SitCoach targets office workers, a group which is often also
assisted by break reminder applications on their PCs. Such
applications are developed to prevent their users from
repetitive strain injuries. Although such applications show
to be successful in reducing complaints [7], they may not
always be pleasant to use [10]. Morris et al. [10] introduced
SuperBreak, which stimulates break compliance for
computer usage. Instead of the usual breaks offered by
software packages such as XWrits and WorkRave,
SuperBreak offers the possibility to make the break time
more productive. By offering the user the possibility to
interact with the PC through gestures during the break,
break compliance is promoted and the productivity during
the break time is increased. Hence, although SuperBreak
may increase break compliance for computer work, it does
not target a reduction in sitting time. Moreover, neither of
the computer packages support break compliance during
other sedentary time, e.g. during meetings or while reading.</p>
      <p>After describing the SitCoach application in the next
chapter, we present a first pilot user experiment to assess
the usability of the application. Through a locus of control
questionnaire and by means of a semi-structured interview,
we gather additional insights on opportunities and
techniques to promote sitting break compliance.</p>
      <p>INTRODUCING SITCOACH
SitCoach is an iPhone application that measures physical
activity by means of the built-in accelerometer. The
application records active time and sitting time at a
granularity of one minute.</p>
      <p>To fight sitting time and inspire people to take a break once
in a while, the SitCoach reminds users after a configurable
number of in-active minutes via visual, acoustic and tactile
messages. Users set their goals in terms of maximum
number of consecutive sitting minutes and number of active
minutes per day.</p>
      <p>Identifying Sitting Time
Using the built-in accelerometer in the smart phone, the
UHVX¶ DFWLY\ VL FODVLIHG QL DQ DFWHLY GDQ LDFWHQY DWHV
Every sHFGRQ D DHVUPXQW RI WHK RSKH¶VQ [ \ GDQ ]
positioning is taken by the accelerometer. These three
values are compared with the previous measurement. When
the difference for x,y or z exceeds 0.3 the accelerometer
recognizes a movement. The 0.3 was determined
empirically: it is low enough to pick up the walking
movement of the user without getting a false reading from
other possible movements like a small turn with the chair
while sitting.</p>
      <p>To distinguish walking from other smaller movements like
a small turn or just standing up from a chair the movement
will be monitored over a certain interval of time. An
empirically determined value of 5 seconds proved to be
sufficient.</p>
      <p>Creating Sedentary Awareness
To motivate users to become more active, the application
stores the number of active minutes per day for each of the
users. This provides a social nudge for users to see how
others are doing and to comply with the social norm.</p>
      <p>When it is time to take a break, SitCoach emits a tactile
(vibration) and an acoustic warning. Users can override the
acoustic warning. A visual indicator at the main screen
shows when a user is moving, giving the user immediate
feedback about their current behavior. Figure 1 provides a
screenshot of the main screen of SitCoach. The green circle
indicates that the application has detect that the user is
currently moving and hence the number of active minutes is
increasing while in this state. In the state displayed in the
figure, the user is nine inactive minutes away from a break
reminder. However, if the user is active for a period equal
to the actual time of the sitting break, the break timer will
be reset.</p>
      <p>A FIRST USER EVALUATION
To assess the usability and user acceptance of the
application, SitCoach has been evaluated with users. This
evaluation also provides insights into HWK SDUWLFQV¶
current sitting behavior and their awareness of the
harmfulness of sedentary behavior. The goal of the study is
to identify future directions for persuasive applications
targeting sedentary awareness.</p>
      <p>In the study, the participants are provided with an iPhone
with the SitCoach application and are invited to use the
application throughout a day at the office. At the end of the
day, a semi-structured interview is conducted, to discuss
experiences. Moreover, the participants are questioned
about current sitting break habits and the awareness of the
importance of such breaks is assessed. Apart from the
interview, two questionnaires were handed to the
participants: one focusing on the utilitarian and hedonic
qualities of the application [5,6] and a second one focusing
on the locus of control that people perceive with respect to
possibilities to reduce their sitting time [13].</p>
      <p>Participants
Eight participants (four females) were invited to participate
in the experiment, during one working day. All participants
were knowledge workers with high computer dependability.</p>
      <p>Procedure and Design
The participants were scheduled on a day they described as
a typical office day. Per participant, a day was selected
without having appointments outside the office during
working hours.</p>
      <p>In the morning after arriving at the office, the participants
received a fully charged iPhone 3G. SitCoach was the only
application installed, apart from the standard software. The
participants were instructed not to use the phone for other
purposes. No SIM card was installed, limiting the
functionalities of the phone.</p>
    </sec>
    <sec id="sec-2">
      <title>During the intake meeting, the participants were explained</title>
      <p>the functionality of the applications and guided through the
features and settings. The standard break timer was set to
60 minutes, prompting for a 5 minute break. The standard
activity goal was set to 50 minutes. The participants were
free to change the settings throughout the day.</p>
      <sec id="sec-2-1">
        <title>URGX$Q OFRN¶ LQ WHK DWIRHUQ HWK SDUWLFQV UHZ</title>
        <p>interviewed based on a list of pre-defined questions on their
sitting behavior, sedentary awareness and the SitCoach
application. Moreover, the two questionnaires were handed.</p>
      </sec>
    </sec>
    <sec id="sec-3">
      <title>The Attrakdiff2 questionnaire was presented to assess both</title>
      <p>the pragmatic and hedonic qualities of SitCoach [5,6]. His
scores on both qualities are important for the prolonged
usage of a product. Specifically, the questionnaire measures
perceived pragmatic quality, hedonic quality identification
HL GRHV HWK SURFWGX RFWUHLEXQ RW WHK HUV¶X LGHWQ\ LQ D
social context?), hedonic quality stimulation (i.e., does the
product help to develop skills or knowledge) and
attractiveness (is the product good, bad or ugly?). Each of
those four categories contains seven word-pairs on a seven
point semantic-differential scale (e.g. discouraging vs.
motivating, complicated vs. simple).</p>
      <sec id="sec-3-1">
        <title>7R HDVWKSHUGFLY ROXV RIFWUQO RHFOXLQIR¶V</title>
        <p>sitting behavior, a locus of control questionnaire was
assessed [13]. The commonly used questionnaire,
developed by Wallton et al., is adapted for sitting behavior.
The questionnaire measures whether the control over the
sitting behavior is determined internally (i.e. self-control;
example statement: If I take care of myself, I can avoid long
sitting periods), by others (e.g. Whenever I feel I sit too
much and too long, I should consult a trained professional .)
or by chance (e.g. No matter what I do, I 'm likely to have
long sitting periods).</p>
        <p>Results
All participants indicated that they were not aware of the
harmfulness of sedentary behavior itself. When taking a
break and getting up from their desk, the participants did so
because they were aware of the adverse effects of
prolonged computer usage and the healthfulness of physical
activity. Half of the participants reported to be unhappy
with the amount of sitting time during a day in the office.</p>
      </sec>
    </sec>
    <sec id="sec-4">
      <title>Suitable moments to take a sitting break are in between tasks and when feeling less concentrated. The time spent during such breaks is not seen as productive.</title>
    </sec>
    <sec id="sec-5">
      <title>The lack of control is seen as the largest source of</title>
      <p>annoyance with PC break applications. Only one of the
participants is using an RSI prevention program on the PC,
which is installed by default. The others have disabled it.</p>
    </sec>
    <sec id="sec-6">
      <title>For a mobile application to create sedentary awareness, the perceived control over the sitting breaks should remain with the user.</title>
    </sec>
    <sec id="sec-7">
      <title>The interviews showed that the phone vibration to signal break alerts was appreciated as it is discrete and easy to ignore when needed, for example during meetings. On the other hand, the buzzing signal was experienced to be</title>
      <sec id="sec-7-1">
        <title>GWUDFLVQJ :³ QHK , DP ZRLQUJN , GRWQ¶ DWZQ WR EH</title>
      </sec>
      <sec id="sec-7-2">
        <title>UEGWXHLV´</title>
        <p>The Locus of Control questionnaire revealed that six out of
eight participants scored low on the internality dimension
(scores &lt; 18 on a range from 6 to 36), while the other
scored moderate (18  score  24). This implies that the
office workers participating in the study believe that they
have little control over their sitting behavior. With overall
higher scores on the powerful others dimension, it is
believed that others (colleagues, managers) strongly</p>
      </sec>
      <sec id="sec-7-3">
        <title>GLQHWUSKPDFVE¶JRY</title>
      </sec>
    </sec>
    <sec id="sec-8">
      <title>The Attrakdiff2 questionnaire results show favorable scores</title>
      <p>on the pragmatic dimension, implying that the participants
are generally positive about the interaction with the</p>
    </sec>
    <sec id="sec-9">
      <title>SitCoach application. No remarks were made about any</title>
      <p>inaccuracies of the application. This suggests that the
current implementation is well usable to distinguish sitting
time from active time. Lower scores were reported on the
hedonic dimensions, most notably on attractiveness.
ontrol questionnaire.</p>
      <sec id="sec-9-1">
        <title>Participant I nternality Powerful others externality</title>
      </sec>
      <sec id="sec-9-2">
        <title>Chance externality</title>
      </sec>
    </sec>
    <sec id="sec-10">
      <title>Moderate</title>
    </sec>
    <sec id="sec-11">
      <title>Moderate Low Low Low</title>
      <p>Low
Low
Low</p>
    </sec>
    <sec id="sec-12">
      <title>Moderate Low</title>
    </sec>
    <sec id="sec-13">
      <title>High</title>
    </sec>
    <sec id="sec-14">
      <title>High</title>
    </sec>
    <sec id="sec-15">
      <title>High</title>
    </sec>
    <sec id="sec-16">
      <title>Moderate</title>
    </sec>
    <sec id="sec-17">
      <title>Moderate</title>
    </sec>
    <sec id="sec-18">
      <title>High</title>
    </sec>
    <sec id="sec-19">
      <title>High</title>
    </sec>
    <sec id="sec-20">
      <title>Moderate</title>
    </sec>
    <sec id="sec-21">
      <title>Moderate</title>
    </sec>
    <sec id="sec-22">
      <title>Moderate</title>
    </sec>
    <sec id="sec-23">
      <title>Moderate Low Low</title>
    </sec>
    <sec id="sec-24">
      <title>High</title>
      <p>Some of the participants reported battery problems with the
smart phone. Although the participants received a fully
charged phone, the battery time was not enough for the
application to run for the whole working day. Hence, in
future work, solutions should be researched that take the
energy consumption of the phone into account when
running such accelerometer-based applications.</p>
    </sec>
    <sec id="sec-25">
      <title>The functionality to share the activity minutes on FaceBook or other social media was not well received. Similar to the</title>
      <p>Pragmatic Hedonic Hedonic
Quality Quality Quality</p>
      <p>I dentification Stimulatio</p>
      <p>n
High
High
findings of Munson et al. [11], participants did not feel the
need to bother their social network with such details.</p>
      <p>AttrakDif2 questionnaire.
CONCLUSION AND FUTURE WORK
In this paper, we presented an application to assist people to
control their sitting behavior. The mobile application
combines feedback on physical activity with insights on the
UHVX¶ LWVQJ SHULRGV SitCoach was developed to gain
VWLQJKRSHO¶ awareness of their sedentary behavior
and the user acceptance of a break reminder application.</p>
      <p>With SitCoach, we have created an application that detects
sitting time with fair accuracy. However, the users involved
in the trial showed not to be in the right stage of change to
be responsive to the strategies applied in SitCoach.</p>
      <p>Persuasive strategies to stimulate the user to take sitting
breaks are likely to be more successful after having
established awareness of the adverse health effects of sitting
behavior. This can be done by first providing insights in
¶HRQ LWJVQ EDHKLRUY QDG EHTXVWOQ\ VHXWLJQ
opportunities to reduce sitting time. For users who are
aware of the problem and the adverse effects of their
behavior, the triggers applied in SitCoach may be revisited.</p>
      <p>ACKNOWLEDGMENTS
This work was funded by the European Commission, within
the framework of the ARTEMIS JU SP8 SMARCOS
project ± 100249 - (http://smarcos-project.eu).</p>
      <p>REFERENCES
1. Consolvo, S., Everitt, K., Smith, I., &amp; Landay,
-$ 'HVLJ³Q THLU5XWPQV RUI 7RLVOQJHFK DWK
RFHU(DJQX 3LFDVK\O F$WLY´\ 3VJUGRLQFHI ,+&amp;
457-66.
3.
9.</p>
      <p>E6WUX +% K¶6)LVQHWS³ RFU(DQXLJ 3LFDOVK\
WFL$Y\KZDQ,WHUFLYS&amp;RXP*DH´ S8ERL&amp;P
2006.
with Personal,</p>
      <p>-63.</p>
      <p>Fujiki, Y (2010). iPhone as a Physical
Activity Measurement Platform. In Proceedings of the
2010 ACM Conference on Human Factors in Computing
Systems (CHI).</p>
      <p>Hamilton, M.T., Healy, G.N., Dunstan, D.W.,
Zderic, T.W., and Owen, N. (2008). Too little exercise
and too much sitting: Inactivity physiology and the need
for new recommendations on sedentary behavior. Current
Cardiovascular Risk Reports 2(4), 292-298.</p>
      <p>Hassenzahl, M. (2006) Hedonic, emotional and
experiental perspectives on product quality. In Ghaoui, C.
(ed) Encyclopedia of Human-Computer Interaction.</p>
      <p>Hershey: Idea group, 226-272.</p>
      <p>Hassenzahl, M. (2010) Attrakdiff. Retrieved
August 11th 2010 from
http://www.attrakdiff.de/en/AttrakDiff-/What-isAttrakDiff/Scientific-Background.</p>
      <p>Heuvel, S.G. van den, Looze, M de, Hildebrandt,
V.H., and The, K.H (2003). Effects of software programs
stimulating regular breaks and exercises on work-related
neck and upper-limb disorders. Scand J Work Environ</p>
      <p>Health 29(2):106± 116.</p>
      <p>MONARCA: A Persuasive Personal Monitoring System to
Support Management of Bipolar Disorder</p>
      <p>Gabriela Marcu
Human-Computer Interaction Institute</p>
      <p>Carnegie Mellon University
5000 Forbes Ave, Pittsburgh, PA, USA</p>
      <p>gmarcu@cs.cmu.edu
ABSTRACT
MONARCA is a persuasive mobile phone application
designed to support the treatment and management of bipolar
disorder. Behavioral data is monitored through both sensing
and manual patient input, while timely feedback is provided
based on clinical recommendations to help patients adjust
their behavior and manage their illness. This paper presents
the design process behind the MONARCA system and
initial findings on the challenge of designing a persuasive
system for the management of bipolar disorder. We discuss
how difficult the design of such technology has turned out
to be, for two primary reasons: (1) the inherent challenges
of using persuasive metaphors with a complex mental
illness, and (2) the tradeoffs encountered due to varying, and
sometimes conflicting, stakeholder needs.</p>
      <p>Author Keywords
Bipolar disorder, mental illness management, user-centered
design, personal monitoring systems
ACM Classification Keywords
H.5.2 Information Interfaces and Representation: User
Interfaces – User-centered design. J.4 Social and behavioral
systems: Psychology.</p>
      <p>INTRODUCTION
Persuasive personal monitoring systems seem promising for
the management of mental illnesses such as bipolar disorder.</p>
      <p>Bipolar disorder is characterized by recurring episodes of
both depression and mania, with treatment aiming to reduce
symptoms and prevent recurrence throughout a patient’s
lifetime. By applying pervasive healthcare technologies to
the treatment of bipolar disorder, we can monitor patients’
behavioral and mood data, and provide timely feedback to
them in order to help them adjust their behavior. This data
supports the treatment and management of the illness in a</p>
      <p>Jakob E. Bardram</p>
      <p>IT University of Copenhagen
Rued Langaards Vej 7, Copenhagen, Denmark
+45 7218 5311
bardram@itu.dk
multitude of ways. For example, patients and their clinicians
can use the data to determine the effectiveness of
medications, find illness patterns and identify warning signs, or test
potentially beneficial behavior changes. Behavioral data
collected could be used to predict and prevent the relapse of
critical episodes.</p>
      <p>Despite the plethora of research into personal monitoring
systems targeting behavior change [8], health-related
behavior change (e.g., physical activity [5, 1], diet [9], cardiac
rehabilitation [6], and others [3]), and even the management
of chronic illnesses (e.g., diabetes [7, 11], chronic kidney
disease [10], asthma [4]), mental illness has remained
relatively unexplored. One explanation for this untapped
potential is the complexity and variation of a mental illness like
bipolar disorder, which causes uncertainty in how to manage
it. Moreover, there is no simple connection between
measurable parameters and the course of treatment; mental illness is
fundamentally complex and is often tied into physical health
problems as well as social problems. In the MONARCA
project we aim to overcome this challenge by developing a
system that, through pervasive data collection and feedback
to the patient, supports the treatment of bipolar disorder.</p>
      <p>
        As such, the MONARCA system can be classified as a
persuasive technology [
        <xref ref-type="bibr" rid="ref2">2</xref>
        ], similar to other persuasive
healthrelated ubiquitous computing systems. The design of such
persuasive systems is, however, extremely difficult. It is
very unclear how feedback should be given to the patient in
order to influence and change behavior. Numerous studies
have proven that that trying to change unhealthy behavior
such as smoking, drinking, or lack of exercise is extremely
difficult even with the use of intensive counseling. Medicine
compliance is also a fundamentally hard problem in
healthcare. Therefore, it is quite challenging – some would
say naïve – to rely on non-human actors like computers and
mobile phones to be able to change unhealthy behavior.
      </p>
      <p>In this paper, we describe the user-centered design process
and initial findings on the challenge of designing a
persuasive system for the management of bipolar disorder. We
discuss how difficult the design of such technology has
turned out to be, for two primary reasons: (1) the challenges
of using persuasive metaphors with a complex mental
illness, and (2) the tradeoffs encountered due to varying, and
sometimes conflicting, stakeholder needs.</p>
      <p>METHOD</p>
    </sec>
    <sec id="sec-26">
      <title>Patients and clinicians of a bipolar disorder treatment pro</title>
      <p>gram took part in an in-depth participatory design process.
They were instrumental in decision-making about features
through collaborative design workshops and iterative
prototyping. Patients participated in semi-structured interviews
about the treatment and management of their own illness to
further inform the design process. Notes and artifacts from
these design activities were analyzed for 1) an
understanding of each stakeholder's motivations and needs, and 2)
indicators of tradeoffs that arose in the design of the
system.</p>
      <p>Workshops were held every other week for six months. At
every workshop, 1-3 individuals attended from each of the
following three stakeholder groups: patients, clinicians, and
designers. The designers led each three-hour workshop by
facilitating discussion about particular design goals and
issues; system features and functionality; and feedback on
mockups and prototypes of the system. During initial
workshops, overall goals of the system were introduced from
both clinical and technical perspectives. Sharing these
perspectives of the project involved drawing from their
respective best practices: both medically and practically,
clinicians know what works with patients; and designers are
aware of related systems and technologies.</p>
      <p>Design activities at workshops began in the early stages
with hands-on brainstorming. We provided materials such
as documents summarizing the goals of the system, images
of existing tools and methods, large poster paper, writing
materials, scissors, tape, etc. The sketches that came out of
this initial brainstorming formed the basis for the first
mockups. For the rest of the process, at each workshop we</p>
    </sec>
    <sec id="sec-27">
      <title>1) discussed a few design goals and system features in depth, and 2) received feedback on the next iteration of the mockups. Mockups presented during workshops progressed from sketches to wireframes to interactive prototypes.</title>
      <p>SYSTEM DESIGN</p>
    </sec>
    <sec id="sec-28">
      <title>The design process resulted in 5 focus areas for a persuasive system for bipolar disorder: self-assessment, activity monitoring, historical data overview, coaching &amp; selftreatment, and data sharing.</title>
      <p>Self-assessment
Subjective data is collected through a mobile phone using a
simple one-page self-assessment form. Less than 10 items
are entered by the patient on a daily basis, including mood,
sleep, level of activity, and medication. Some items are
customizable to accommodate patient differences, while
others are consistent to provide aggregate data for statistical
analysis. A simple alarm reminds the patient to fill out the
form.</p>
      <p>Activity monitoring</p>
    </sec>
    <sec id="sec-29">
      <title>Using sensors in the phone, objective data is collected to</title>
      <p>monitor level of engagement in daily activities (based on</p>
    </sec>
    <sec id="sec-30">
      <title>GPS and accelerometer), and amount of social activity (based on phone calls and text messages). This data is abstracted for analysis, to protect the patient’s privacy while still supporting self-assessment using objective data.</title>
      <p>Historical overview of data</p>
    </sec>
    <sec id="sec-31">
      <title>The patient and clinician will both have access to the data through a web interface. This will give them the means to explore the data in depth by going back and forth in time, and focusing on specific sets of variables at a time.</title>
      <p>Coaching &amp; self-treatment</p>
    </sec>
    <sec id="sec-32">
      <title>Psychotherapy will be supported through everyday rein</title>
      <p>forcement in two ways. Customizable triggers can be set to
have the system notify both patient and clinician when the
data potentially indicates a warning sign or critical state.</p>
    </sec>
    <sec id="sec-33">
      <title>Second, after patients are advised by their clinicians about which actions to take in response to warning signs, they can keep track of and review them through the system.</title>
      <p>Data sharing
In order to strengthen the psychotherapy relationship data
and treatment decisions are shared between the patient and
his/her clinician. Similarly, sharing data with family
members or other caregivers empowers the patient to support the
treatment process. Finally, sharing data among patients
helps with personal coping and management efforts by
reassuring patients that they are not alone, and helping them
see how others manage their illness.</p>
      <p>CHALLENGES WITH A PERSUASIVE METAPHOR
One of the main original goals of the user-centered design
process was to design a persuasive system for bipolar
patients, which could help them constantly adjust their
behavior to manage their own illness. In particular, the design
process revealed the following three parameters were
crucial to keeping a bipolar patient stable:
1. adherence to the prescribed medication – i.e., ensuring
that the patient takes his or her medication on a daily
basis</p>
    </sec>
    <sec id="sec-34">
      <title>2. stable sleep patterns – e.g., sleeping 8 hours every night and going to bed at the same time</title>
    </sec>
    <sec id="sec-35">
      <title>3. being physically and socially active – e.g., getting out</title>
      <p>of the home, meeting with people, going to work.</p>
      <p>Now – at first glance, this may seem simple, but numerous
studies have shown that each of the above three things are
very difficult to achieve for many patients, and achieving
all three consistently is inherently challenging in
combination with a mental illness. Hence, the core challenge is to
create technology that would help – or “persuade” – the
patient to do these three things every day.</p>
      <p>Most persuasive health-related Ubicomp systems have
adopted different metaphors with the goal of motivating the
patient to perform healthy behavior. Examples of such
metaphors include a garden that grows when the person is
physically active; a fish that grows when the person walks
more; and a dog that is happier when the person eats
healthy meals. Common to these metaphors is a
simple-tounderstand relationship between behavior (e.g. exercise)
and visualizations in the metaphor (e.g. more flowers in the
garden).</p>
      <p>In the design of the MONARCA project, we tried to adopt
the same strategy of creating a metaphor. In total of 5
different metaphors were tested and tried out in a series of
design workshops. These metaphors included the use of an
abstract color picture, a landscape with a river, a dartboard,
a music equalizer, and a scale. The patients and clinicians
rejected all of these metaphors – one after the other.</p>
      <p>Why did this happen? First we thought that maybe we were
just bad at designing the metaphors, and we kept on trying
with new ones. But since it turned out to be a persistent
“problem”, we think that something more fundamental was
at stake, which was expressed by one of the patients as:</p>
      <p>“I do not want my illness to be reduced to a game.”
We think that this is an important insight into the design of
persuasive technologies for healthcare and
selfmanagement. Many of the technologies and metaphors
reported so far deal with personal lifestyle related health
management, which is fundamentally different from
patients with a diagnosed mental illness. We think that the
design of feedback to the patient needs to follow another
pattern other than using a metaphor.</p>
      <p>DESIGN TRADEOFFS
During the user-centered design process, we discovered
several tradeoffs in the design of the system due to
conflicting stakeholder needs and motivations. These tradeoffs
relate to the clinical efficacy of the system, the patient’s
privacy, sustained use of the system, and other issues. In this
section, we highlight two of the primary tradeoffs we dealt
with during the design of MONARCA.</p>
      <p>Clinically driven vs. patient driven strategies
If a system has a strong clinical focus – meaning that it
adopts only clinically proven treatment strategies – it could
miss out on patient-driven approaches that may be helpful to
some patients. In addition, the system may also ignore novel
technological solutions that the clinical field has yet to
evaluate. Since our system was designed for a clinical
context, it was important that it adhere to clinical practices so
that it could be evaluated as a valid intervention. In addition,
considering clinical practices was crucial in designing a
system to be viable for adoption and acceptance into a patient's
treatment, which includes everyday use by the patient and
occasional use by the clinician.</p>
      <p>The clinicians that took part in our design activities shared
with us scenarios, anecdotes, and commonalities about the
treatment of their patients. We understood the context we
were developing the system for by understanding the
practices of clinicians with their patients. A recurring theme was
clinicians' limited resources. This turned into a limitation for
the functionality of the system, because if something took
too much time or attention on the clinician's part, the
clinicians would reject it. An example of one such feature was
the system suggesting that the patient contact the clinic if
data collected indicated possible warning signs – and
making it easy for the patient to place this call. The motivation
behind this feature was to encourage the patient to reach out
for help when needed, but the clinicians ultimately rejected
the idea because we could not find a reasonable protocol to
make the benefits to the patient outweigh the burden on the
clinic's resources. Features of the system also couldn't
present a liability for clinicians, so they were more likely to
reject ideas and limit the role of the system to be on the safe
side. Any kind of text messages or notes written by the
patient and made available to the clinic were kept out of our
design, because we could not ensure that the clinicians
would always read these messages, so we could not make
them liable for their content.</p>
      <p>We therefore realized that designing our system with
primarily a clinical focus was limiting. The clinicians we
worked with were clearly most comfortable with strategies
that they were familiar with, they had evidence for based on
their experiences with patients, and were backed by clinical
trials. Deviating from these practices somewhat, and pushing
our clinicians a little bit out of their comfort zone, enabled
us to explore other potential strategies, from the perspectives
of the patients and the designers.</p>
      <p>An additional example of a debated feature is reported stress
level. A stress level scale was strongly rejected by a
clinician who argued that stress is not a clinically useful
measure, nor is there any clinical definition of stress that would
support accurate data collection. Interestingly, a second
clinician was the one who suggested the stress level scale, and
argued for it from a very patient-centered perspective based
in psychotherapy. This clinician found that external stressors
play a significant part in the mood of her patients, and it was
useful for her to consider a patient's reported stress level
when assessing how that patient was doing. She also
believed that patients would find it useful to assess their own
level of stress, regardless of the fact that they would be
interpreting its meaning for themselves in the absence of a
clinical definition. The patients tended to agree with her, so
although this feature was under debate for several weeks, the
designers opted to keep it in the design because enough
participants believed there could be personal value in assessing
one's stress.</p>
      <p>The patients were creative in suggesting strategies based on
their personal experiences. Knowing what behavioral
changes have worked for them in the past, and imagining
what new strategies might work for them, patients explored
technological solutions unrestrained by considerations of
clinical efficacy. This unrestrained creativity was productive
during the design process for two reasons. First, it revealed
what would motivate the patients to use the system, which is
critical to adoption and acceptance. Second, it helped us
realize which measures, though clinically significant, would
ultimately fail because they were too intrusive for the patient
to collect, or were not interesting enough to the patient to
motivate collection.</p>
      <p>Egocentric patient bias vs. clinician generalizations
Although patients provide valuable insights into the
experience of living with and managing bipolar disorder, their
input tends to be egocentric, since their knowledge about the
disorder mostly comes from their own personal experience
with it. Discussions about the amount and type of data to
collect were complex due to the different experiences and
motivations of the stakeholders: clinicians were interested in
data they knew to be relevant for assessment based on
clinical studies or their own experiences treating patients; and
patients were interested in data they thought would be useful
to themselves personally for self-reflection. To balance these
sometimes opposing interests, designers focused on what
data would be easy and convenient to collect. Without
nonintrusive data collection methods, the system will be
overloaded with features and burden the patients, who are
responsible for collecting the data every day. Here, the
designers play an important role in keeping in perspective the
implications of collecting different amounts and types of data.</p>
      <p>Patients and clinicians disagreed about how to include
customizable personal warning signs, which patients would
personalize and track on a daily basis. In addition to the
universal warning signs that we selected with the help of
clinicians to be applicable to most, if not all, patients, we
discussed including personal warning signs that each patient
could customize based on personal symptoms. Clinicians
argued that there should be as few of these items as possible,
even stating that one personal warning sign was difficult
enough for patients to attempt to track in their daily life. On
the other hand, patients argued that having more flexibility
would allow them to explore multiple warning signs at once
in order to determine which ones applied to them. One
patient, who had difficulty understanding her illness and could
not identify any of her personal warning signs, asked for a
lot flexibility because she would have no idea what to track,
so she would need to try many different items. The designers
found a solution by suggesting that the feature be limited but
flexible. The agreed upon solution would allow patients the
option to include as few as one personal warning sign, but
no more than three. Those patients who would only be able
to handle one item at a time could customize the system to
show only one at a time.</p>
      <p>CONCLUSION
In the design of a persuasive personal monitoring system
for bipolar disorder, we ran into several challenges unique
to using persuasive technology for the management of
mental illness. Our findings demonstrate that the design of a
system for bipolar disorder is quite different from that of
systems that have been explored for other health purposes
such as nutrition, physical activity, and chronic physical
illnesses. In this paper we have highlighted some of the
main issues that emerged during our design process,
including using a persuasive metaphor, balancing clinical- and
patient-centered strategies, and dealing with the biases of
patient and clinician participants. Our work revealed major
challenges due to the complexity of the illness, stigma
surrounding the illness, and the often-conflicting needs of
clinicians and patients.</p>
      <p>ACKNOWLEDGMENTS
This work has been partially funded by the EU Contract
Number 248545 - MONARCA under the 7th Framework
Programme. We would like to thank our participants for
their contributions to this project and enthusiasm for the
work.</p>
      <p>Building Persuasion Profiles in the Wild: Using Mobile
Devices as Identifiers.</p>
      <p>Maurits Kaptein</p>
      <p>Eindhoven University of Technology / Philips Research</p>
      <p>Den Dolech 2, 5600MB, the Netherlands. m.c.kaptein@tue.nl
ABSTRACT
Tailoring — presenting the right message at the right
time — has long been identified as one of the core
opportunities of persuasive systems. In this paper we
describe a scenario in which an adaptive persuasive
system which identifies users by the Bluetooth key of their
mobile phone is used to promote energy savings. By
describing this simplistic system and its possible
implementation we identify several key-criteria of adaptive
persuasive systems.</p>
      <p>Author Keywords
Persuasive Technology, Influence strategies
ACM Classification Keywords
H.1.2 User/Machine Systems: Software psychology.</p>
      <p>INTRODUCTION
CHI2010 attendees were presented with a choice on
entering the conference hotel: A large revolving door
provided access to the hotel while next to it was a
sliding door—some things simply do not fit through a
revolving door. With the air conditioning in full
operation revolving doors are efficient at keeping the heat in.</p>
      <p>Sliding doors, however, are not. To help save energy a
paper-sign was put up: “Please take the revolving door”.</p>
      <p>A brief observation proved the paper-sign to be
effective just over half the time: 60% of the visitors took
the revolving door. This scenario, the “Revolving Door
Problem”, offers a framework to describe adaptive
persuasive systems. By further elaborating this scenario
and exploring a solution we describe the neccesities and
difficulties that arise when designing adaptive
persuasive systems.</p>
      <p>The Promises of Persuasive Technology
There are three reasons why employing a persuasive
system might be more effective than the current
papersign: (1) Persuasive technologies function as social
actors and can use social influence strategies, (2) they can
be context aware, and (3) they can adapt to individual
users [5, 8]. While the paper-sign is probably located
at the right place and at the right time—when visitors
make their choice—the current version does not
implement social influence strategies and does not adapt to
its users.</p>
      <p>
        Social Influence Strategies
Cialdini [
        <xref ref-type="bibr" rid="ref2">2</xref>
        ] shows how small changes to messages—such
as the message on the door—can increase their
effectiveness. For example, a message in a hotel room asking
guests to “reuse their towels” compared to a message
stating “Join your fellow citizens in helping to save the
environment ” led to a difference in towel re-usage of
28.4% [7]. To structure thes types of messages Cialdini
[
        <xref ref-type="bibr" rid="ref2">2</xref>
        ] identifies six social influence strategies: Authority,
Consensus, Reciprocity, Liking, Scarcity, and
Commitment. The message in the towel re-usage example
implements the Consensus strategy: people act like other
people do. A message (e.g.) stating that “The general
manager of this hotel requests you to re-use...” would
implement the Authority strategy. These social
influences strategies can easily be used to improve upon the
effectiveness of the paper-sign.
      </p>
      <p>The final promise of persuasive technologies however—
adapting influence attempts to individuals—will
require some kind of interactive system. While
adaptation of persuasive strategies to responses by
users is mentioned early on in the literature on
persuasive technologies Fogg [5, e.g.] we are unaware
of any actual implementations.</p>
      <p>Individual Differences
There is growing evidence that individuals differ in their
responses to influence strategies: Constructs like Need
For Cognition [1] predict the response of individuals to
the usage of social influence strategies. More concretely,
Kaptein et al. [9] show that usage of influence strategies
for individuals who are low susceptible to these
strategies can lead to backfiring: for a portion of participants
in their study compliance to a request was lower when
the social influence strategy was presented. Next to this
overall tendency to respond to influence strategies, some
individuals seem more likely to respond to one specific
strategy—e.g. an authority argument—while others are
more influenced by implementations of other strategies.</p>
      <p>Cialdini et al. [3] shows that there are sizable and stable
individual differences in people’s responses to the
commitment strategy. Similar results have been obtained
when looking at the consensus strategy: Self-reported
susceptibility to this strategy highly correlates with
behavioral responses to this strategy [10].</p>
      <p>These individual differences in susceptibility to
different persuasive strategies imply that persuasive systems
should personalize the way in which they attempt to
influence individuals. Such a class of systems, which we
call adaptive persuasive systems, are an unexplored area
in that we still need to understand how to model, design
and build these systems. This paper takes a concrete
but simple example that encapsulates the quintessence
of this problem to discuss how to address these
challenges.</p>
      <p>SOLVING THE REVOLVING DOOR PROBLEM?
Returning to the revolving door problem, let us consider
what is involved in implementing an adaptive persuasive
system. We need to (A) identify the visitors entering the
lobby—minimally by giving each a unique ID, and (B)
measure the effectiveness of a presented message. The
Bluetooth key of visitor’s mobile phone could be used
for identification [11]. This will capture around 12% of
the visitors entering the lobby. This same identification
method can also be used to measure the effectiveness of
each persuasive attempt: One Bluetooth scanner next
to the revolving door and one next to the sliding door
could determine which entrance was used by the current
visitor. Based on this knowledge about the visitor and
records of earlier decisions a message implementing the
right influence strategy can be selected. In the
remainder of this paper, we focus on the mechanism by which
these strategies can be selected.</p>
      <p>Suppose we have only two messages to show, one
implementing the authority strategy—“The general manager
of this hotel urges you to...” (A)—and one
implementing the consensus strategy—“80% of our visitors always
use...etc.” (B). The system then needs a mechanism to
choose the message that is most likely to be effective
for the current visitor. It is intuitive that for a new
visitor the system should present the message which has
lead to the highest compliance for other, previously
observed, visitors. If this message is successful then there
is no need to try different messages on subsequent visits.</p>
      <p>However, when the selected message is not effective, it
might become attractive to present another message on
the next visit. This decision logically depends on the
initial succes probabilities of the messages under
consideration, the variance of effectiveness of messages
between visitors, and the number of succes’s or failures
observed for the current visitor. A collection of estimates
of the effectiveness of different influence strategies for
an individual is called a Persuasion Profile and can be
used to select the most-likely-to-be effective message on
a next visit.</p>
      <p>Formalizing the Adaptation Problem
The probability of a single visitor taking the revolving
door on multiple occasions can be regarded a binomial
random variable B(n, p) where n denotes the number
of approaches the visitor has made to the doors and p
denotes the probability of success: the probability of
taking the revolving door. Given M messages one can
compute for each individual, for each message,
probability pm = km/nm where km is the number of observed
successes after representation of message m, nm times
to a specific visitor. It makes intuitive sense to present
a visitor with the messages with the highest pm.</p>
      <p>For a large number of observations N of one visitor this
would make perfect sense. However, this will not inform
a decision for a newly observed visitor. For a new visitor
one would present the message m for which pm is
maximized over previously observed visitors1. Actually—
given Stein’s result [4]—for every user a weighted
average of the pm for an individual user and those of other
users—one where the estimated pm for an individual is
“shrunk” toward the population mean—will provide a
better estimate than an estimate based on observations
of a single visitor alone. E.g., if the authority message is
effective 70% of the time over all visitors and only 30%
percent of the time for the specific visitor under
consideration, the best estimate of the (real) effectiveness of
the authority message pA for this visitor is a weighted
average of these two.</p>
      <p>Adapting to Individuals
To include both the known effectiveness of a message
for others, and a specific visitors previous responses to
that same message, into a new estimate of message
effectiveness, pm, we use a Bayesian approach. A
common way of including prior information in a binomial
random process is to use the Beta-Binomial model [12].</p>
      <p>The Beta Beta(α, β) distribution functions as a
conjugate prior to the binomial. If we re-parametrize the
beta distribution as follows</p>
      <p>π(θ|µ, M ) = Beta(µ, M )
where µ = α+αβ and M = α + β, then the expected
value of the distribution is given by: E(θ|µ, M ) = µm.</p>
      <p>In our scenario this represents the expected probability
of a successful influence attempt by a specific message.</p>
      <p>The certainty of this estimated success probability is
represented by:</p>
      <p>V ar(θ|µ, M ) = σ2 =
µ(1 − µ)</p>
      <p>M + 1
After specifying the probability of success µm of
message m and the certainty about this estimate σm2 we can
treat this as our prior expectancy about the
effectiveness of a specific message and update this expectancy
by multiplying it by the likelihood of the observation(s)
to obtain the distribution of our posterior expectation:
p(θ|k) ∝ l(k|θ)π(θ|µ, M )
=</p>
      <p>Beta(k + M µ, n − k + M (1 − µ))
1This is assuming the error costs—the effects of presenting
the wrong message—are equal for each message.
!"#$%&amp;'("# ) *+&amp;,"-%.* ) /0# ) %-/('+-&amp;%-1 ) &amp;,0%&amp;+.2 )!"#$%&amp;$'()*
+-&amp;0*!"..+.)")-'*3+#)0/)*+"-.)45625789)
:"-; ) !+#.'".%&lt;+ ) .$#"$+1%+.2 ) .'&amp;, ) ". ) .+(/=*0-%$0#%-12)
!+#.0-"(%&gt;"$%0-2)$"%(0#%-12)"-?).0&amp;%"()&amp;0*!"#%.0-)45782)#+(;)
0- ) %-/0#*"$%0- ) "30'$ ) $,+ ) '.+#@. ) &amp;0-$+A$ ) "-? ) "&amp;$%&lt;%$%+.9)
B-?++?2 ) $C0 ) 0/ )D+#?%&amp;,+&lt;.E; ) "-? ) F+'+-.&amp;,C"-?+#@.)
!#%-&amp;%!(+.)!0%-$)$0)!#'+&amp;,-)".)")&lt;"('+)0/)!"#$%&amp;'("#)&amp;0-&amp;+#-G</p>
      <p>BHI J,+)&amp;#+"$0#.)0/)")!+#.'".%&lt;+)$+&amp;,-0(01;)*'.$)+-.'#+)
$,"$)%$)#+1"#?.)$,+)!#%&lt;"&amp;;)0/)'.+#.)C%$,)"$)(+".$)".)
*'&amp;,)#+.!+&amp;$)".)$,+;)#+1"#?)$,+%#)0C-)!#%&lt;"&amp;;9
HI K+#.'".%&lt;+ ) $+&amp;,-0(01%+. ) #+(";%-1 ) !+#.0-"()
%-/0#*"$%0- ) "30'$ ) " ) '.+# ) $0 ) " ) $,%#? ) !"#$; ) *'.$ ) 3+)
&amp;(0.+(;).&amp;#'$%-%&gt;+?)/0#)!#%&lt;"&amp;;)&amp;0-&amp;+#-.9)4L8
:03%(+ ) !,0-+. ) &amp;"- ) &amp;"!$'#+ ) "- ) '-!#+&amp;+?+-$+? ) "*0'-$ ) 0/)
%-/0#*"$%0- ) "30'$ ) $,+ ) '.+#2 ) .'&amp;, ) ". ) (0&amp;"$%0- ) &amp;00#?%-"$+.2)
&amp;"((.2)"-?)$+A$)*+.."1+.2)"&amp;&amp;+-$'"$%-1)$,+)-++?)/0#)"$$+-$%0-)
$0)!#%&lt;"&amp;;)45M89)D'$)&amp;,"--+(.).'&amp;,)".)"'?%02)!,0$01#"!,.2)
"-?)!#0A%*%$;)"(.0)&amp;"!$'#+)%-/0#*"$%0-)"30'$)0$,+#.)-+"#3;
N%-?%#+&amp;$).$"E+,0(?+#.)4O89)B-)$,+%#)+*!%#%&amp;"().$'?;)0/)$++-)
."/+$;).&amp;+-"#%0.2)P&gt;+.E%.)"-?)&amp;0((+"1'+.)(+"#-+?)$,"$)$++-.)
C+#+ ) *0#+ )#+('&amp;$"-$ )$0) %-?%#+&amp;$(;) .,"#+ )%-/0#*"$%0- )"30'$)
$,+%#)&amp;0-$+A$)"-?)"&amp;$%&lt;%$%+.)C%$,)/#%+-?.@)!"#+-$)$,"-)$0).,"#+)
.'&amp;, ) %-/0#*"$%0- ) C%$, ) $,+%# ) 0C- ) !"#+-$. ) 4O89 ) J,'.2 ) %- ) ")
*03%(+)&amp;0-$+A$2)%$)%.) )%*!0#$"-$)$0)&amp;0-.%?+#)$,+)!#%&lt;"&amp;;)0/)
&amp;0*!"-%0-.)"-?)3;.$"-?+#.N-0$)0-(;)$,+)'.+#9
Q($,0'1,)!#%&lt;"&amp;;)%.)%*!0#$"-$)$0)*"-;)KBFP).$#"$+1%+.2)C+)
.,0'(? ) 10 ) 3+;0-? ) !#%&lt;"&amp;; ) $0 ) "&amp;&amp;0'-$ ) /0# ) &lt;"('+. ) .'&amp;, ) ".)
'.")/'/-0 * ,(%#/"$-2 ) "-? ),&amp;12)"$$) 45R8 ) C,+- ) $,+; ) "#+)
%*!(%&amp;"$+? ) 3; ) $,+ ) *+"-. ) '.+? ) $0 ) "//+&amp;$ ) 3+,"&lt;%0#9 ) ) S0#)
+A"*!(+2 ) &amp;0-.%?+# ) $,+ ) &lt;"('+ ) 0/ )'.")/'/-2 ) T!+0!(+@.)
'-?+#.$"-?%-1 ) 0/ ) C,0 ) $,+; ) "#+ ) 0&lt;+# ) $%*+U ) 45R89 ) J,+)
!+#.'".%&lt;+).$#"$+1;)0/)$(,'&amp;1*1"&amp;#)')32)!#0&lt;%?%-1)T*+"-.)$0)
03.+#&lt;+)0$,+#4.8)C,0)"#+)!+#/0#*%-1)$,+%#)$"#1+$)3+,"&lt;%0#.)
"-?)$0).++)$,+)0'$&amp;0*+.)0/)$,+%#)3+,"&lt;%0#U)45782).,0'(?)3+)
*0#+ ) +//+&amp;$%&lt;+ ) C,+- ) 03.+#&lt;+#. ) .,"#+ ) "- ) %?+-$%$; ) C%$, ) $,+)
03.+#&lt;+?9)S'#$,+#2)%/)C+)"#+)T*"##%+?U)$0)0'#)&amp;+(()!,0-+.2)
C+ ) C%(( ) 3+ ) *0#+ ) "$$"&amp;,+? ) $0 ) "!!(%&amp;"$%0-. ) $,"$ ) #+/(+&amp;$ ) 0'#)
%?+-$%$%+.9)Q.)"-0$,+#)+A"*!(+2)&amp;(%#/"$- *"-? ),&amp;12)"$$) "#+)
%*!(%&amp;"$+?)3;)$+&amp;,-0(01%+.)$,"$)'.+)$,+)$%33"$/'()).$#"$+1;9)
Q($,0'1,).'11+.$%0-.)*'.$)3+)1%&lt;+-) )"$)$,+)#%1,$)$%*+)"-?)
!("&amp;+)$0)"//+&amp;$)3+,"&lt;%0#)45682).'11+.$%0-.).,0'(?)3+)!0(%$+)
"-? ) "((0C ) $,+ ) '.+# ) $0 ) #+*"%- ) !+"&amp;+/'( ) "-? ) &amp;0*!0.+?N
'-(+..)$,+#+)%.)"-)0&lt;+##%?%-1)#+".0-)$0)0$,+#C%.+9)
!"#$%&amp;'(#)$*+$#,-)$./&amp;01#/$%&amp;'(#)2
Q.)-0$+?)%-)$,+)%-$#0?'&amp;$%0-2)&lt;"('+.)'-?+#(;)!+#.'".%0-9)B-)
!+#.'"?%-1).0*+0-+)$0)"&amp;$)%-)0-+)C";)"-?)-0$)"-0$,+#2)C+)
"#+)"..+#$%-1)$,"$)$,+)?+.%#+?)3+,"&lt;%0#)C%(()#+.'($)%-)")3+$$+#)
0'$&amp;0*+9 ) D+$$+# ) /0# ) C,"$V ) D+$$+# ) /0# ) 0'# ) ,+"($,2 ) /0# ) 0'#)
/"*%(;@. )."/+$;2 )/0#)-"$%0-"().+&amp;'#%$;2 )/0# )$,+)+-&lt;%#0-*+-$2)
"-?).0)0-9)B*!(%&amp;%$)%-)+&lt;+#;)"&amp;$)0/)!+#.'".%0-)%.)")&lt;"('+)$,+)
!+#.'"?+#)C"-$.)$0).'!!0#$2)")$"#1+$)&lt;"('+9
D+#?%&amp;,+&lt;.E;)"-?)F+'+-.&amp;,C"-?+#)"??#+..)$,#++)!#%-&amp;%!(+.)
$0)$,+)+-?.)0/)!+#.'".%0-G</p>
      <p>BI</p>
      <p>J,+)%-$+-?+?)0'$&amp;0*+)0/)"-;)!+#.'".%&lt;+)$+&amp;,-0(01;)
.,0'(?)-+&lt;+#)3+)0-+)$,"$)C0'(?)3+)?++*+?)'-+$,%&amp;"()
%/ ) $,+ ) !+#.'".%0- ) C+#+ ) '-?+#$"E+- ) C%$,0'$ ) $,+)
$+&amp;,-0(01;)0#)%/)$,+)0'$&amp;0*+)0&amp;&amp;'##+?)%-?+!+-?+-$(;)
0/)!+#.'".%0BBI J,+)*0$%&lt;"$%0-.)3+,%-?)$,+)&amp;#+"$%0-)0/)")!+#.'".%&lt;+)
$+&amp;,-0(01;).,0'(?)-+&lt;+#)3+).'&amp;,)$,"$)$,+;)C0'(?)3+)
?++*+? ) '-+$,%&amp;"( ) %/ ) $,+; ) (+? ) $0 ) *0#+ ) $#"?%$%0-"()
!+#.'".%0-9
HBBBI )J,+)W0(?+-)X'(+)0/)K+#.'".%0-G)J,+)&amp;#+"$0#.)0/)")
!+#.'".%&lt;+)$+&amp;,-0(01;).,0'(?)-+&lt;+#).++E)$0)!+#.'"?+)
" ) !+#.0- ) 0# ) !+#.0-. ) 0/ ) .0*+$,%-1 ) $,+; ) $,+*.+(&lt;+.)</p>
      <p>C0'(?)-0$)&amp;0-.+-$)$0)3+)!+#.'"?+?)$0)?09)4L8
Q(( ) $,#++ ) !#%-&amp;%!(+. ) /0&amp;'. ) 0- ) '-"&amp;&amp;+!$"3(+) +-?. ) /0#)
!+#.'".%0-9 ) J,+; ) !#0&lt;%?+ ) -0 ) 1'%?"-&amp;+ ) ". ) $0 ) C,"$ ) +-?.)
C0'(?)3+)?+.%#"3(+9)Q$$+-$%0-)$0)&lt;"('+.)&amp;"-)(+"?)$0)?+.%#"3(+)
+-?. ) /0# ) 3+,"&lt;%0# ) &amp;,"-1+9 ) B-?++?2 ) *'&amp;, ) !+#.'".%&lt;+)
$+&amp;,-0(01;),".)+A!(%&amp;%$(;)$"#1+$+?),+"($,)0#)+-&lt;%#0-*+-$"()
.'.$"%-"3%(%$;9 ) Q($,0'1, ) $,+.+ ) "#+ ) ("'?"3(+ ) 10"(.2 ) !+#,"!.)
C+ ) .,0'(? ) "(.0 ) 3+ ) ?+.%1-%-1 ) !+#.'".%&lt;+ ) $+&amp;,-0(01; ) $,"$)
,+(!.)'.)$0)0&lt;+#&amp;0*+)0'#)#"&amp;%"()3%".+.)Y4#"".(2*4#(2*5'&amp;$I2)
&amp;0-$#0()0'#)"-1+#)Y,&amp;12)"$$I2)"-?)(+"#-)$0),+(!)"-?)#+(;)0-)
0'#)-+%1,30#.)Y/#%$/I9)S'#$,+#2)%$)%.)%*!0#$"-$)$0)'-?+#.$"-?)
$,+)&lt;"('+.)0/)$,0.+)C+)"#+)?+.%1-%-1)/0#9
3&amp;'(#$/#,)4*,)
J,+ ) *0.$ ) 03&lt;%0'. ) &lt;"('+ ) $+-.%0-. ) %- ) KBFP ) $+&amp;,-0(01; ) !%$)
?+.%#+? ) 3+,"&lt;%0# ) &amp;,"-1+. ) "-? ) ) $,+ ) &lt;"('+. ) $,+; ) %*!(%&amp;"$+)
"1"%-.$ ) $,+ ) %-$+-$%0- ) $0 ) &amp;,"-1+ ) 3+,"&lt;%0# ) "-? ) *+$,0?.) /0#)
?0%-1).09)J,"$)%.2)+-?.)&amp;"-)3+)%-)$+-.%0-)C%$,)*+"-.9)Z+)
.++)!#0*0$%-1),+"($,2)+-&lt;%#0-*+-$"().'.$"%-"3%(%$;2)"-?).0)
0-2)&lt;+#.'.)!#+.+#&lt;%-1)"'$0-0*;2)!#%&lt;"&amp;;2)"-?).0)0-9)
[0C+&lt;+#2)$,+.+)"#+)-0$)$,+)0-(;)$;!+.)0/)$+-.%0-.9))S%#.$2)$,+)
"&amp;$ ) 0/ ) !+#.'".%0- ) %-,+#+-$(; ) !#%&lt;%(+1+. ) $,+ ) &lt;"('+. ) 0/ ) $,+)
!+#.'"?+# ) 0&lt;+# ) $,0.+ ) 0/ ) $,+ ) !+#.'"?+?9 ) D; ) ".E%-1 ) ;0' ) $0)
&amp;,"-1+);0'#)3+,"&lt;%0#2)B)"*).";%-1)$,"$)*;)&lt;"('+.)"#+)*0#+)
%*!0#$"-$)$,"-);0'#)&lt;"('+.)Y0#)"$)(+".$2)$,+)&lt;"('+.);0').++*)
$0 ) 3+ ) "&amp;$%-1 ) 0-I9 ) B- ) $,+ ) 3+.$ ) &amp;".+2 ) ". ) %- ) 3+,"&lt;%0# ) &amp;,"-1+)
.'!!0#$).;.$+*.2)$,+)!+#.'"?+#)"-?)$,+)!+#.'"?+?)"1#++)0-)")
&lt;"('+ ) .'&amp;, ) ". ) ,+"($, ) 0# ) +-&lt;%#0-*+-$"( ) .'.$"%-"3%(%$;\ ) $,+)
!+#.'"?+# ) !#0&lt;%?+. ) %-/0#*"$%0- ) 0# ) .'!!0#$ ) $0 ) ,+(! ) $,+)
!+#.'"?+?)"&amp;$)%-)"&amp;&amp;0#?"-&amp;+)C%$,)$,%.).,"#+?)&lt;"('+9)
]+&amp;0-?2 ) !+0!(+ ) *"; ) "1#++ ) 0- ) &lt;"('+. ) 3'$ ) ?%."1#++ ) 0-)
!#%0#%$%+.9)Z+)*%1,$)"1#++)$,"$)+-&lt;%#0-*+-$"().'.$"%-"3%(%$;)
%.)C0#$,C,%(+N3'$)B)*%1,$)#"$+)$,+)&amp;0*/0#$)0#)+A&amp;%$+*+-$)
0/ ) ?#%&lt;%-1 )". ) *0#+ )%*!0#$"-$9 )B-?++?2 )X0E+"&amp;, )&amp;0*!"#+?)
%-?%&lt;%?'"(.@)&lt;"('+).;.$+*.).0(+(;)0-)$,+)3".%.)0/)?%//+#+-&amp;+.)
%-)$,+%#)#"-E%-1.)0/)").+$)0/)!#+?+/%-+?)&lt;"('+.)4R589
5&amp;6#$7#"&amp;%4*08$-4++#0#,/$%&amp;'(#)
S%-"((;2))!+0!(+)*";)"1#++)0-)")?+.%#+?)3+,"&lt;%0#2)3'$),"&lt;+)
?%//+#+-$ ) #+".0-. ) /0# ) &lt;"('%-1 ) $,"$ ) 3+,"&lt;%0#9 ) S0# ) +A"*!(+2)
/%&lt;+ ) !+0!(+ ) *%1,$ ) &amp;,00.+ ) $0 ) ?#%&lt;+ ) 3+(0C ) $,+ ) .!++? ) (%*%$2)
!"#$ % &amp;'( % )$!*( % '+, % (!"-',-.% )' % '/!0 % )$! %!"#1 % )' % 2(')!#)%
$"%&amp;'(1% )'% 2("#)*#! %')*+%'1 % )' % (!34#! % 3!2!,3!,#! % ', % &amp;'(!*5,%
'*6%",3%2(')!#) %,"'+-,"!.$&amp;/0*+'(1%'(%)'%(!34#!%)$!%,!!3%&amp;'(%
'*6%3(*66*,5%",3%#',)(*/4)!%)'%&amp;,1+*-,2&amp;,'"!.$0$'"+,"3+!+'(4
7-%8'55%2'*,)-%'4)9%)$!%:'/*6!%2$',!%*-%",%*,)*:")!%3!;*#!%
&lt;=&gt;?%@&amp;%*)%3'!-%,')%-$"(!%'4(%5'"6-9%/4)%(")$!(%$"-%5'"6-%'&amp;%*)-%
'+,9 %+!%&amp;!!6 %/!)("0!3 %&lt;A&gt;?%B$! %-":!%+'463%-!!: %)'%$'63%
&amp;'(%;"64!-?%C422'-!%)$")%:0%$*5$!-)%;"64!%*-%)$!%-"&amp;!)0%'&amp;%
:0 % #$*63(!,? % @&amp; % @ % "3'2) % " % :'/*6! % "226*#")*', % )' % $!62 % :!%
";'*3%-2!!3*,59%",3%*)%-$'+-%:!%2*#)4(!-%'&amp;%2'6"(%/!"(-9%@%
+*66 % /! % 42-!)? % D!#"4-! % *) % #$"66!,5!- % :0% ;"64!-9 % @ % -!! % )$!%
"226*#")*', % "- % " % )$(!") % )' % :0% "4)',':09 % ",3 % @ % !E2!(*!,#!%
2-0#$'6'5*#"6 % (!"#)",#! % &lt;F&gt;G6!"3*,5 % :! % )' % 3(*;! % !;!,%
&amp;"-)!(?%@,-)!"39%@%-$'463%/!%(!:*,3!3%'&amp;%:0%;"64!%'&amp;%-"&amp;!)0?
@%-!!%)+'%"22('"#$!-%)'%"33(!--*,5%*,3*;*34"6%4-!(-H%;"64!-?%
8*(-)9 %3!-*5,!(-H %;"64! %#'::*):!,)-%-$'463%/!%:"3! %#6!"(%
)$('45$%/(",3*,5%",3%)$!%*,&amp;'(:!3%#',-!,)%2('#!--9%-'%)$")%
4-!(-%#",%:"I!%*,&amp;'(:!3%#$'*#!-?%C!#',39%*,)!(&amp;"#!-%-4#$%
"-%B'339%J'5!(-9%",3%K"0,!H-%*,&amp;'(:")*;!%5('#!(0%-$'22*,5%
#"() % &lt;LM&gt; % -$'463 % /! % )"*6'("/6!? % B$!0 % -$'463 % 42$'63 % 4-!(%
"4)',':0% /0% "66'+*,5 % 4-!(- % )' % #$''-! % +$*#$ % *,&amp;'(:")*',%
":',5 % ;"64!N6"3!, % '2)*',- % O!?5?9 % -4-)"*,"/*6*)09%
$!"6)$&amp;46,!--9 % ",3 % #'-)P % )' % 3*-26"0 % :'-) % 2(':*,!,)60? % 7%
3",5!(%*-%)$")%4,3*-#6'-!39%*,;'64,)"(0%)"*6'(*,5%:"0%#('--%
&amp;(':%2!(-4"-*',%)'%:",*246")*',%&lt;FQ9FR&gt;?
!"#!$%&amp;'"#
7))!,)*', % )' % ;"64!- % :"0 % #',)(*/4)! % ,') % ',60 % )'%
4,3!(-)",3*,5%!)$*#"6%*--4!-%'&amp;%:'/*6!%K@ST%)!#$,'6'50G
/(*,5*,5 % "))!,)*', % )' % #',#!(,- % /!0',3 % 2(*;"#0 % ",3%
3*-#6'-4(!G/4) % "6-' % )' % *,#(!"-*,5 % )$!*( % -#'2! % ",3%
!&amp;&amp;!#)*;!,!--G)$!*(%2'+!(%)'%3'%5''3%*,%)$!%+'(63?%84()$!(%
+'(I%-$'463%#6"(*&amp;0%('6!%'&amp;%)$!-!%;"64!-%)$('45$%!:2*(*#"6%
",3%)!#$,*#"6%*,;!-)*5")*',-%'&amp;%K@ST%)!#$,'6'50?
()*)()#!)&amp;
F?76!"$:"39%B?9%!)%"6?%8*-$*,5%&amp;'(%-4-)"*,"/*6*)0.%B$!%!&amp;&amp;!#)-%'&amp;%
*,3*(!#)%",3%3*(!#)%2!(-4"-*',?%@,.56'4.73$'*"/'$.89:.;&lt;&lt;=9%7TU%</p>
      <p>K(!--%OLVV=P?
L?7,3!(-',9%C?%T'!(#*',?%@,%&gt;)&amp;.?'",%-*@.5,/(/!-A&amp;@+".-% .</p>
      <p>B)+!-$-A)(%OLVVWP9%$))2.XX26")'?-)",&amp;'(3?!34X!,)(*!-X#'!(#*',
M?D!(3*#$!;-I09%Y?%",3%S!4!,-#$+",3!(9%Z?%B'+"(3%",%!)$*#-%'&amp;%</p>
      <p>2!(-4"-*;!%)!#$,'6'50?%878C%[L9%Q%OU"0%FAAAP9%QFNQ=?
[?T*"63*,*9%J?D?%:,%!0&amp;,/&amp;D.&gt;)&amp;.?/+&amp;,/&amp;.-%.B&amp;*$0"$+-,9%T'66*,-9%</p>
      <p>(!;*-!3%!3?%OFAA=P?
Q?T\!-I*-9%7?9%!)%"6?%K"(!,)*,5%&amp;(':%)$!%2'#I!).%]"64!%)!,-*',-%",3%
)!#$,*#"6%3*(!#)*',%&amp;'(%-!#4(!%",3%2(*;")!%2"(!,)N)!!,%:'/*6!%
-"&amp;!)0?%@,%B*-/4.?EFB?.;&lt;G&lt;9%7TU%K(!--%OLVFVP?
W?Y";*-9%^?%Z)$*#"6%3!-*5,%:!)$'3-%&amp;'(%2!(-4"-*;!%)!#$,'6'50?%@,%</p>
      <p>B*-/4.B5H?F7?:I5.;&lt;&lt;J9%7TU%K(!--%OLVVAP?
R?Z-6":/'6#$*6"(9%K?9%_*6-',9%U?`?9%a"I6!09%@?%K@ST.%K!(-4"-*',9%
*,&amp;64!,#!9%,435!9%",3%#'!(#*',%)$('45$%:'/*6!%3!;*#!-?%B'%
"22!"(K.56'4.73$'*"/'$.89:.;&lt;GG9%7TU%K(!--%OLVFFP?
Y?%Z#I6!-%O!3-?P9%C-3+!&amp;.B&amp;*$0"$+-,K%C)",&amp;'(3%T"2)'6'50%U!3*"%</p>
      <p>OLVVRP9%QNFF?
A?8'559%D?^?%@,#(!"-*,5%2!(-4"-*',%)$('45$%:'/*6*)0?%@,%D?^?%8'55%
",3%Y?%Z#I6!-%O!3-?P9%C-3+!&amp;.B&amp;*$0"$+-,K%C)",&amp;'(3%T"2)'6'50%</p>
      <p>U!3*"%OLVVRP9%FQQNFWM?
FV?8'559%D?^?%B&amp;*$0"$+1&amp;.&gt;&amp;/),-!-L(D.F$+,L.8-2A0'&amp;*$.'- .</p>
      <p>8)",L&amp;.M)"'.M&amp;.&gt;)+,N.",@.O-K.U'(5",%b"4&amp;:",,%OLVVMP?%
FF?8(*!3:",9%D?9%c'+!9%Y?9%",3%8!6)!,9%Z?%@,&amp;'(:!3%T',-!,)%*,%
)$!%U'\*66"%D('+-!(.%@:26!:!,)*,5%]"64!NC!,-*)*;!%Y!-*5,?%@,%
B*-/&amp;&amp;@+,L$.-%.')&amp;.PQ').9"#"++.:,'&amp;*,"'+-,"!.8-,%&amp;*&amp;,/&amp;.-, .</p>
      <p>?($'&amp;2.?/+&amp;,/&amp;$%OLVVLP?
FL?8(*!3:",9%D?9%b"$,9%K?c?%^(?9%",3%D'(,*,59%7?%]"64!%C!,-*)*;!%</p>
      <p>Y!-*5,%",3%*,&amp;'(:")*',%-0-)!:-.%B$(!!%#"-!%-)43*!-?%@,%K?%d$",5%
",3%Y?%e"66!))"%O!3-?PK.%902",R8-2A0'&amp;*.:,'&amp;*"/'+-,.",@ .</p>
      <p>C","L&amp;2&amp;,'.:,%-*2"'+-,.?($'&amp;2$D.S-0,@"'+-,$4%U?%Z?%C$"(2!%</p>
      <p>OLVVWP9%M[=NMRL?
FM?8(*!3:",9%D?9%",3%S*--!,/"4:9%c?%D*"-%*,%#':24)!(%-0-)!:-?%</p>
      <p>78C.&gt;E:?%GT9%MOFAAWP9%MMVNM[R?
F[?^'$,-',9%Ye?9%",3%U46;!09%^?U?%7##'4,)"/*6*)0%",3%#':24)!(%</p>
      <p>3!#*-*',%-0-)!:-?%878C.P=K.FL%OFAAQP9%Q=NW[?
FQ?b"2)!*,9%U?%",3%Z#I6!-9%Y?%C!6!#)*,5%!&amp;&amp;!#)*;!%:!",-%)'%",0%</p>
      <p>!,3?%@,%B*-/4.B5H?F7?:I5.;&lt;G&lt;9%`STC%WFMR%OLVFVP9%=LNAM?
FW?`!;*,!9%Y?%f-*,5%)!#$,'6'50%)'%2(':')!%-!E4"6%$!"6)$?%@,%D?^?%
8'55%",3%Y?%Z#I6!-%O!3-?P9%C-3+!&amp;.B&amp;*$0"$+-,K%C)",&amp;'(3%</p>
      <p>T"2)'6'50%U!3*"%OLVVRP9%FQNF=?
FR?U*#$"6-I*9%^?%Z)$*#"6%3",5!(-%'&amp;%:'/*6!%2!(-4"-*',?%@,%D?^?%
8'55%",3%Y?%Z#I6!-%O!3-?P9%C-3+!&amp;.B&amp;*$0"$+-,K%C)",&amp;'(3%</p>
      <p>T"2)'6'50%U!3*"%OLVVRP9%FMRNF[L??
F=?a*,"-Nb4II',!,9%c?%D!$";*'(%#$",5!%-422'()%-0-)!:-.%7%
(!-!"(#$%:'3!6%",3%"5!,3"?%@,%B*-/4.B5H?F7?:I5.;&lt;&lt;=9%`STC%</p>
      <p>QVMM%OLVV=P9%FW[NFRW?
FA?a*,"-Nb4II',!,9%c?%",3%c"(g4:""9%U?%%7%-0-)!:")*#%
&amp;(":!+'(I%&amp;'(%3!-*5,*,5%",3%!;"64")*,5%2!(-4"-*;!%-0-)!:-?%@,%</p>
      <p>B*-/4.B5H?F7?:I5.;&lt;&lt;=9%`STC%WFMR%OLVFVP9%[NF[?
LV?K"5!9%J?Z?%",3%b("09%T?%Z)$*#-%",3%2!(-4"-*;!%)!#$,'6'50.%7,%
!E26'(")'(0%-)430%*,%)$!%#',)!E)%'&amp;%$!"6)$0%6*;*,5?%@,%B*-/4.S+*$' .
:,'4.M-*N$)-A.-,.U0@L&amp;.",@.:,%!0&amp;,/&amp;.')*-0L).C-3+!&amp;.O&amp;1+/&amp;$9%
85FH.M-*N$)-A.B*-/&amp;&amp;@+,L$.VJ&lt;%OLVFVP9%FANLL?
LF?J'I!"#$9%U?%&gt;)&amp;.U"'0*&amp;.-%.902",.I"!0&amp;$?%8(!!%K(!--%OFARMP?
LL?B$"6!(9%J?%c?%",3%C4,-)!*,9%T?J?%U0@L&amp;D.:2A*-1+,L.O&amp;/+$+-,$ .</p>
      <p>"3-0'.9&amp;"!')K.M&amp;"!')K.",@.9"AA+,&amp;$$K%h"6!%f,*;!(-*)0%K(!--%</p>
      <p>OLVV=P?
LM?B'339%K?U?9%J'5!(-9%h?9%",3%K"0,!9%C?^?%S435*,5%)$!%#"()%*,%
)$!%-42!(:"(I!)1%c'+%:4#$%*-%!,'45$%*,&amp;'(:")*',%&amp;'(%&amp;''3%
-$'22!(-i%@,%B*-/4.S+*$'.:,'4.M-*N$)-A.-,.U0@L&amp;.",@.:,%!0&amp;,/&amp; .
')*-0L).C-3+!&amp;.O&amp;1+/&amp;$9%85FH.M-*N$)-A.B*-/&amp;&amp;@+,L$.VJ&lt;.</p>
      <p>OLVFVP9%LMNLW?
L[?_"-$*,5)',9%^?%B$!%,!+%3*5*)"6%3*;*3!?%O&amp;$.C-+,&amp;$.H&amp;L+$'&amp;*.</p>
      <p>O^",4"(0%A9%LVFFP9%F779%Q77?
LQ?_("09%J?%7&amp;(*#"%-!!-%:"--*;!%5('+)$%*,%:'/*6!%+!/%4-"5!9%</p>
      <p>L0"*@+",4/-40N%OY!#!:/!(%L9L%LVVAP9%
$))2.XX+++?54"(3*",?#'?4IX)!#$,'6'50XLVVAX3!#XLLX:'/*6!2$',
!-N*,)!(,!)?
Opportunities and Challenges in Mining Behavioral
Economics to Design Persuasive Technology</p>
      <p>Min Kyung Lee
Human-Computer Interaction Institute</p>
      <p>Carnegie Mellon University
Pittsburgh, PA 15213 USA</p>
      <p>mklee@cs.cmu.edu
ABSTRACT
Behavioral economics examines people’s decision making
processes in everyday situations. I argue that behavioral
economics can provide a repertoire of a tool that can inform
the design of persuasive technology. In this position paper,
I propose strategies drawn from behavioral economics, and
identify opportunities and challenges in applying the
strategies to the design of persuasive technology. This
position paper is a modification of the paper [16].</p>
      <p>Author Keywords
Persuasive technology, behavioral economics, decision
making, decision bias, choices
ACM Classification Keywords
H5.m. Information interfaces and presentation (e.g., HCI):
Miscellaneous.</p>
      <p>General Terms
Design
INTRODUCTION
The role of information technology in people’s daily
decision making is steadily growing. For example, we
decide which route and transportation to take to visit a
friend’s house, which restaurant to go for dinner, or which
grocery products to buy based on the information and
choices presented in information technology applications.</p>
      <p>This change offers tremendous opportunities for
humancomputer interaction (HCI) researchers to provide
interventions to assist people to make self-beneficial or
prosocial choices.</p>
      <p>As one way to promote self-beneficial choices, we suggest
approaches drawn from the field of behavioral economics.</p>
      <p>Behavioral economics examines the gamut of large and
small decisions people make about such choices as how
much to invest in retirement savings, whether to join a
health club, and whether to eat a delicious but caloric candy
bar. The persuasive element in this approach consists of
presenting choices in a way that leverages people’s decision
processes and induces them to make self-beneficial choices
[17].</p>
      <p>We argue that designs for HCI that leverage behavioral
economics theory and research are a highly promising
avenue for persuasive technologies. Although widely
discussed outside the HCI and design communities in both
academic and popular arenas (e.g., [24]), this approach has
not yet influenced our field. The message of behavioral
economics is simple: people are susceptible to decision
bias, which often makes it hard for them to make
selfbeneficial choices. Thus, we should present choices in a
way that helps people to make self-beneficial choices and
understand the implications of their decisions as well—all
without restricting their freedom of choice.</p>
      <p>In this paper, I explain several behavioral economics
theories and discuss opportunities and challenges in
applying the theories to the design of persuasive
technology.</p>
      <p>APPLYING BEHAVIORAL ECONOMICS
Departing from the premise of economics that people make
rational choices, behavioral economists have shown that
people’s decision making processes are biased by various
situational factors, such as the manner in which options are
presented and the times when the choices are offered, and
the emotional or visceral state of the person at the time of
choice [1, 12]. This understanding of people’s decision
biases provides a rich repertoire of tools that designers can
leverage. In this section, we present five decision biases and
discuss how these biases can be leveraged in the design of
persuasive technology.</p>
      <p>Default Bias
When people make choices, they tend to favor the default
option or the status quo, rather than taking the time to
consider and then adopt an alternative state [11, 21]. People
tend to take “the path of least resistance,” and keep doing
what they have been doing, or doing what comes
automatically, even when they can make improvements.</p>
      <p>The reasons for this decision bias could have roots in
people’s limited attention and tendency to “satisfice” [21],
their perception that an organization’s selection of a default
option constitutes a recommendation (see [6]), and the
implied popularity of the default option.</p>
      <p>Default biases have been blamed for a wide range of
undesirable outcomes, including Americans’ excessive
consumption of fries and large sodas as part of “supersized”
meals at McDonald’s [17]. Yet if carefully designed, the
default bias can be a powerful tool to propel people toward
self-beneficial behaviors (see [5, 23]).</p>
      <p>Opportunities
Convenience and salience. HCI design can leverage the
default bias in many ways, by making healthy choices more
convenient and salient physically and cognitively. In the
domain of snacking, featured healthy snacks can be made
easy to access, e.g., on websites, on vending carts, and so
forth. For example, on a website, the checkbox of healthy
snacks among available options could be selected as the
default, reducing the need to select one of these options
explicitly. Or when presenting sale items at a bakery, a
system could filter and first offer items that are made with
whole grain flours. For a kiosk system, the placement of
buttons, the number of clicks or the number of screens a
user has to access to choose an item could be decreased or
increased to change the perceived priority of a snack or
sandwich order.</p>
      <p>An eldercare robot working in a nursing home could
organize the physical placement of food in a way that the
healthy food is placed closer to an elder’s room. In addition,
a snack delivery robot might only deliver healthy snacks to
people’s offices, but require people to walk to the robot to
get unhealthy snacks.</p>
      <p>Convenience can be further leveraged using sensing
technologies that tell people when they are near healthy
snacks. For instance, if shoppers are in a food court in a
mall, the system could present healthy choices to them via
mobile phone as convenient food options.</p>
      <p>Default bias is different with other biases presented in the
paper; leveraging default bias can be effective, even with
those who are not motivated to change their potentially
problematic behaviors, or are not aware of issues with their
current behaviors [16].</p>
      <p>Attention span. People might be more subject to default
bias when their attention spans are limited or when they do
not have enough time to do exhaustive search. HCI
technology can target moments when people’s attention
spans are limited, such as when they are using mobile
devices on the move, or when people are making decisions
with limited time, such as when they are ordering food in a
fast-food restaurant, or making choices in a public kiosk.</p>
      <p>Interface components can be also designed to manipulate
people’s attention spans. The use of banners or graphic
images may be distracting [1], reducing people’s
attentiveness and efforts in making decision.</p>
      <p>Challenges
Depending on the way it is implemented, the default
strategy may harm people’s experience of making a choice
[16]. Explicitly suggesting a certain options as default may
cause people to feel forced to make those choices. Careful
design of the strategy and iterative testing of its efficacy
and its impact on people’s experiences will be important.</p>
      <p>Another caveat in using default strategy might be its lack of
educational effect. In comparison to persuasive techniques
that use informative messages (e.g., indicating
consequences of choices), the default strategy do not
provide any information that people can use to reflect on
their behaviors and learn the consequences of their choices.</p>
      <p>If users are subsequently put in a new environment without
the interventions, the changed behaviors may not continue.</p>
      <p>Designers using the default strategy should be aware of this
potential problem, and consider using them with
educational methods. New research is needed to understand
the long-term effects of these techniques.</p>
      <p>Present-biased preference
Present-biased preferences represent people’s tendency to
weigh the pros and cons of present choices more heavily
than future choices, and to underestimate their needs in the
future. This decision bias is also known as “time
discounting” [18]. The tendency typically promotes
unhealthy eating because the immediate pull of tasty food is
likely to eclipse considerations of future health
consequences. However, present-biased preferences can be
used to encourage healthier choices if people are asked to
plan ahead. Read and van Leeuwen [19] gave their
participants a choice of snack to be eaten in one week or at
the time of eating, the next week. They found that their
participants chose far more unhealthy snacks for immediate
choice than for advance choice.</p>
      <p>Opportunities
Strategic design of timing of choice. Present-biased
preferences can be leveraged by strategically designing the
time that technology applications prompt users to make
certain choices. Researchers in context-aware technology
have been designing applications that can sense the current
activity of people and learn their routines over time [4]. A
meal planning application or a restaurant reservation system
that nudges people to make a choice when they are less
likely to be hungry (i.e., 1-2 hours after their lunch) might
be as effective as the application that uses persuasive
messages or calorie information, and it might be felt to be
less intrusive.</p>
      <p>Challenges
The success of the planning strategy may depend on
people’s satisfaction with the choice made previously at the
time of consumption. Even when people spontaneously
made choices that would have long-term benefits and
delayed gratification (e.g., granola bars over more delicious
chocolate bar), they may not like their choices anymore at
the moment when they experience the outcomes of their
choices. If this experience continues, people may stop using
the technology or change their minds at the time of
consumption. Systems would need to help people stick with
their choices and influence them to stay happy with their
choices. Messages that remind people of the positive
aspects of their choices may mitigate potential negative
feelings.</p>
      <p>Diversification heuristic
Diversification heuristic or naïve diversification means
people’s tendency to seek variety when making several
choices at once [20, 22]. This bias applies to a lesser degree
when people make the same type of choices sequentially
over time. For example, when people are asked to pick four
snacks for one month at once, they tend to choose four
different snacks; on the other hand, when people are asked
to pick a snack each week, they tend to choose their favorite
snack, having the same four snacks for one month.</p>
      <p>Opportunities
Diversification heuristic can be leveraged by prompting
people to make another choices for the future when they
make short-sighted choices. For example, when people
order an unhealthy snack to eat immediately, the system can
prompt them to make a choice for their next snack. Both
diversification heuristic and present-biased preference
suggest that people are more likely to choose healthy
snacks as their next snack. On the other hand, when people
make healthy choices for immediate consumption, the
system may not prompt them for future choices, so that they
do not choose unhealthy choices for the sake of diversity.</p>
      <p>Challenges
Providing incentives for people to make choices for future
(e.g., a discount) will be important to encourage people to
take another step to make a future choice.</p>
      <p>Licensing effect
Licensing effect refers to people’s tendency to indulge
themselves (i.e., making vice choices) after they make
choices that activate a positive self-concept (i.e., making
virtue choices) [13]. For example, people may feel that they
deserve a high-caloric dessert after having a healthy salad
for lunch. Some research suggests that prior choices can
influence subsequent choices even in different domains. For
instance, after donating their money to a charity, people
may feel licensed to buy a luxurious item for themselves.</p>
      <p>Opportunities
Persuasive technology can adaptively change its
information presentation to help people avoid licensing
effect biases. In a system that tracks people’s previous
choices, when they have made virtuous choices (e.g.,
exercising instead of watching TV on a couch, or
carpooling instead of driving), the system may not show or
emphasize the tracked behaviors in order not to encourage
any licensing behaviors.</p>
      <p>Challenges
There is little consensus on how people make decisions in
responses to their prior choices. Transtheoretical model
suggests that the system needs to applaud people making
progresses in changing their behaviors in relation to their
goals [8]. Licensing effects suggest that emphasizing their
previous good behaviors can induce people to feel deserved
to deviate from the good behaviors. More research is
needed to better understand what factors cause the
differences in their subsequent choices [10].</p>
      <p>Asymmetrically dominated choices
People tend to make choices that are easier to judge as
superior than other alternatives. One example of this
tendency is the “asymmetric dominated choice” [9], which
means placing a choice option next to an inferior option to
increase its attractiveness.</p>
      <p>Opportunities
Asymmetrically dominated choices can be leveraged by
intentionally including an inferior option when presenting
many options. For instance, consider a cookie as compared
to a large, shiny Fuji apple and a small withered apple. By
pairing the Fuji with the withered apple, the Fuji’s value
seems much higher, and choices of the Fuji will increase.</p>
      <p>Challenges
Paring only a few options with obviously inferior ones can
make users feel suspicious about the systems. In addition,
in many choices, finding a clearly inferior option is
difficult, which makes this approach practical only to a
certain type of choices.</p>
      <p>NEEDS FOR SYSTEMATIC DESIGN AND EVALUATION
In the previous sections, I described several decision biases
drawn from behavioral economics, and opportunities and
challenges in leveraging them in the design of persuasive
technology. Theory-based design should be implemented
through iterative design processes and evaluated
systematically to test its efficacy as documented in [16].</p>
      <p>Previous research has showed that some design features do
not work in the real world, even when theory predicted their
effect [1, 16]. In the real world, there might be other factors
that may eclipse the power of the intervention strategy.</p>
      <p>Characteristics of different design media (website, mobile
phone, and/or robot) can influence how theory would work.</p>
      <p>CONCLUSION
Behavioral economics research suggests that extremely
simple changes in user interfaces can have a substantial
impact on people’s choices. In this workshop, I hope to
have a lively discussion on strengths and weaknesses of
design strategies drawn from behavioral economics, and
identify domains and situations where these approaches
would be most appropriate and useful.</p>
      <p>Gathering and Presenting Social Feedback to Change</p>
      <p>Domestic Electricity Consumption
Matthew Studley and Simon Chambers</p>
      <p>University of the West of England
matthew2.studley@uwe.ac.uk</p>
      <p>Ruth Rettie and Kevin Burchell</p>
      <p>Kingston University
r.rettie@kingston.ac.uk
ABSTRACT
This paper describes the CHARM Energy Study in which
mobile technology is used to study the impact of social group
feedback on household energy consumption. We describe
the background and rationale behind the study, the
technology which supports the study, and the study’s methodology.</p>
      <p>The work described herein builds upon similar studies by
using mobile technology and on-line feedback to increase the
frequency of accurate social group feedback to the
participants.</p>
      <p>Author Keywords
Nudge, Social Norms, Smart Meters
ACM Classification Keywords
H.5.2 Information Interfaces and Presentation: User
Interfaces—Evaluation and Methodology
INTRODUCTION
It is widely recognized [10] that lowering domestic energy
consumption could make a significant contribution in
reducing CO2 emissions and hence mitigate against the risk of
anthropogenic climate change and promote economic
wellbeing. There are significant challenges to the achievement of
this goal; to change a household’s energy consumption the
householders must be motivated to change and to have the
tools available to enact this change.</p>
      <p>CHARM is a three-year EPSRC funded UK project that
evaluates the impact of individual and social group feedback
on behaviour in three different contexts, including
electricity consumption. The research aims to develop, evaluate
and understand the ways in which digital technology can be
used to shape individual behaviour by informing and thereby
challenging ‘normal’ practice. Social norm research
suggests that we can influence behaviour by telling people what
other people do [14].</p>
      <p>Traditional approaches that try to change behaviour by
directly influencing attitudes and intentions often prove
inefCopyright (c) 2011 for the individual papers by the papers’ authors.
Copying permitted only for private and academic purposes. This volume is
published and copyrighted by the editors of PINC2011.</p>
      <p>PINC2011
fective [1]. Rather than telling people what to do, it can
be more effective to use ‘social proof’ [6]; influencing
behaviour by showing people what others do. Studies in
several related disciplines suggest that everyday practices are
malleable, and can be ‘nudged’ in a socially desirable
direction by subtle forms of social influence [21]. In particular,
research indicates that feedback on an individual’s level of
performance (e.g. electricity consumption) can change their
behaviour, and moreover, that this effect is enhanced if
supplemented by feedback on the performance of a relevant
social group.</p>
      <p>THEORETICAL FRAMEWORK
Writing from a sociological perspective, Shove [18] explores
the social organization of normality and argues that patterns
of consumption are shaped by the taken-for-granted
practices of everyday life: ‘much consumption is customary,
governed by collective norms and undertaken in a world of things
and socio-technical systems that have stabilizing effects on
routines and habits’ (p. 9). Shove emphasises the
collective conventions that underlie individual conceptions of
basic needs such as cleanliness and comfort. Thus, a
yearround indoor temperature of 22◦C has become an accepted
standard of comfort that shapes buildings, clothing habits
and energy consumption patterns, while daily showering has
become an accepted cleanliness practice in the UK, with
consequent impact on energy and water consumption. These
expectations are taken-for-granted, and treated as inherent
aspects of ‘comfort’ and ‘cleanliness’, but their contingency
is demonstrated by historical and global variation. Although
Shove highlights the complex socio-technical, economic,
cultural and symbolic systems that underlie conceptions of
‘normal’ practices, she argues that what people take to be
normal is not fixed but ‘immensely malleable’ (p. 199).
Consequently, she claims, it is important to understand the
‘dynamics of normalization’, that is, how do the habits and
practices of everyday life change and evolve?
Whereas Shove avoids a rational choice model with its
focus on individual choices, the relatively new field of
behavioural economics retains a focus on individual choice,
but contests the assumption of a rational economic agent,
in the light of research on the psychology of choice. Thaler
and Sunstein[21] argue that choices are inevitably influenced
by the context or ‘choice architecture’, and that it is
legitimate to deliberately ‘nudge’ people’s behaviour in order to
improve their lives. A ‘nudge’ is ‘any aspect of the choice
architecture that alters people’s behaviour in a predictable
way without forbidding any options or significantly
changing their economic incentives’ (p. 6). Thaler and Sunstein
highlight research in social psychology that shows one can
nudge people simply by telling them what other people do.</p>
      <p>Whereas earlier research on conformity [5] [12] relied on
overt social pressure, more recent research [7] has focused
on subtle, indirect influences of which participants may be
unaware; these are more analogous to nudges. Cialdini et
al. [8] distinguish between two types of social norms,
descriptive and injunctive. The former simply state what most
people actually do, the latter express an overtly normative
message about what people should do. Both can be effective,
but descriptive norms are less invasive. Social norm research
typically [14] includes descriptive social norms, e.g. ‘70%
of students on this campus do not take drugs’, and has been
widely used in social-norm marketing campaigns aimed at
alcohol and substance abuse among young people. Research
suggests that the impact of social norms depends on the
extent to which they are focal (i.e. salient) and in alignment
[7].</p>
      <p>Two field studies are directly relevant to electricity efficiency.</p>
      <p>In these studies participants’ electricity meters were read by
research assistants who provided feedback on door-hangers.</p>
      <p>Nolan et al. [13] tested descriptive social norms such as:</p>
      <p>In a recent survey of households in your
community, researchers at Cal State San Marcos found that
77% of San Marcos residents often use fans instead of
air conditioning to keep cool in the summer. Using fans
on energy instead of air conditioning — Your
Community’s Popular Choice!
The study found that these had significantly more effect on
consumption than injunctive appeals to self interest,
protection of the environment or social responsibility, although
respondents in an earlier study (reported in the same
paper) thought that the descriptive norm message would be
least motivational. A study using a similar methodology
by Schultz et al., [17] again used door-hangers, giving
participants feedback on their individual and local
neighbourhood electricity usage figures. This research compared a
feedback only condition (descriptive social norm) with an
intervention than combined feedback with a positive or
negative emoticon or ‘smiley’ (descriptive and injunctive social
norms). In the feedback only condition, participants who
were using more than their neighbours used significantly
less after the intervention, but those who were using less
moved towards the norm, and started to use more
electricity (the ‘boomerang’ effect). In the second condition, when
descriptive and injunctive social norms were combined, the
‘destructive’ movement towards the norm was avoided:
usage of those below the norm remained stable while the usage
of those above declined. Note, these two studies used
personal meters readers attached handwritten feedback to
respondents’ front doors; this personal element may have
enhanced the normative effect of the communication. A large
scale year long trial conducted by Cialdini at Positive Energy
(O Power) combines descriptive and injunctive social norms
in energy bills, with promising results [3].</p>
      <p>
        The study by Schultz et al. combined individual and
social group feedback, but did not distinguish between the
impacts of these two interventions. There is considerable
research on the impact of individual feedback in energy
efficiency. Darby [9] identifies feedback as the single most
promising method for reducing household energy
consumption, and calls for more field testing. Research shows that
more frequent feedback is more effective, and that feedback
can be effectively conveyed through a website [
        <xref ref-type="bibr" rid="ref2">2</xref>
        ]. Research
on social group feedback in energy bills is more
equivocal. Surveys conducted in the US and Norway indicate that
consumers are receptive to comparisons of their energy
consumption with relevant social groups, but Roberts et al. found
the idea of social comparison was unpopular in UK focus
group research [15]. Iyer [11] reviews different expressions
and formats of comparative social feedback and advocates
small comparison groups preferably based on physical
location.
      </p>
      <p>Methodology
We performed two pilot tests, the former involving ten
participants recruited from University staff, the latter twenty
participants recruited from two coherent geographical areas
chosen to represent different socio-economic groups. Due
to the small size of the pilots no statistically valid
inferences can be drawn from their output; these trials were
performed to test technology, recruitment and communications.</p>
      <p>The main study includes four hundred and twenty
participants professionally recruited in these two target areas.
Participants are paid an incentive for their participation.
Recruiters administered a pre-trial questionnaire (e.g.
ascertaining house type, the number of rooms in the house,
heating type, et c..). A matching questionnaire will be
administered after the trial to see what change has taken place in
the way the participants see themselves and their behaviour.</p>
      <p>We believe that the CHARM Energy Study is unique in
using mobile technology to study the effect of frequent
online social feedback in a UK study large enough to enable
statistically-valid conclusions to be drawn.</p>
      <p>Households were randomly assigned to one of three
conditions; control (no feedback), individual feedback only, or
both individual and social group feedback. The control groups
have their energy use monitored but receive no
communications from the team during the study, and do not receive any
feedback on their energy use. We will use the data on the
control groups’ usage to account for environmental factors
which effect electricity use (cold weather, mass use of TV
to watch landmark events, et c.) and to allow us to take into
account the fact that simply having an ‘electricity monitor’
in the home may have an effect on the energy behaviours of
the household.</p>
      <p>In addition to the questionnaires, we will conduct
approximately 35 face-to-face semi-structured interviews, with a
purposive sample of subjects. Interviews will occur in
respondents’ homes and involve as many adult household
members as feasible, and will include observation and discussion
of home configuration, energy efficiency features, types of
energy consumed and appliances used. A number of
respondents will be interviewed both before and after the
experiments, in order to benchmark conceptions and practices and
to facilitate identification of changes (these respondents will
be excluded from the field trial analysis). A number of
respondents will be re-interviewed at least six months after the
trial to identify any long term changes in overall levels and
underlying practices. Respondents will receive an additional
incentive for their participation in the interviews. In
addition, we plan three professionally moderated focus groups,
to elicit discussion of the trials and normative discourse in
a social context; the focus groups will be reconvened after a
period of six months to explore the longevity of any changes
in practices.</p>
      <p>Technology
Each respondent who volunteers to take part in the study is
supplied with a box containing three components
1. A current-clamp which attaches to the meter tail and which
transmits usage data every two seconds via a 433 MHz
wireless link.
2. A monitor which stores this data and sends the data to our</p>
      <p>server via GPRS using a roaming SIM.
3. A power adapter which supplies the monitor with power</p>
      <p>for operation.</p>
      <p>There is no real-time display visible to the individuals in the
household. It has been shown [4] that real-time displays are
a powerful tool in effecting behavioural change since they
promote experimentation to see what effect individual
appliances have upon power consumption, but have not been
included in this study in order to focus on the effects of
social feedback.</p>
      <p>The monitor and current-clamp make use of a
commerciallyavailable off-the-shelf home energy monitor with a real-time
display. We hide the display from view in the box that
contains the GPRS modem and microcontroller. Using a COTS
solution allowed a significant saving in development time
and the time taken to meet regulatory and safety
requirements.</p>
      <p>As a result of field-testing in the pilot studies, the embedded
controller has evolved through several iterations to account
for network outages, automatically reloads new versions of
firmware as we release them, and can be remotely controlled
in situ to trigger recovery from several abnormal conditions.</p>
      <p>Usage information is gathered via GPRS upload by the HTTP
‘GET’ mechanism to a web-server where it is logged in a
relational database. The web-server provides an
passwordcontrolled management interface which allows us to track
the performance of each monitoring unit and participant
household, to determine for example when participants in a
household have not viewed their data on the website, and to track
the frequency of data transmission from monitors enabling
the team to track network outages, request user interventions
such as checking the unit is receiving power, ask the
householder to reboot the unit, et c..</p>
      <p>Feedback
Information is supplied to the participants in the individual
and social experimental groups in a number of ways. They
can view information about their electricity use on the
website (see below). They receive weekly emails which
encourage them to maintain their participation in the study.
Individuals known to be infrequent visitors to the website may
receive SMS text messages prompting them to participate, a
mechanism which was shown to be an effective way of
encouraging re-engagement in the initial field trial.
As previously stated, households are assigned to one of three
experimental groups which define the type of feedback they
receive. The feedback provided to households in the social
feedback category is illustrated in fig. 1. We hope to
create the conditions where we may most easily see an effect
of social proof in changing behaviour in the following ways.</p>
      <p>Firstly, we attempt to increase saliency as recommended in
[7] and focus on small geographic areas as recommended in
[11]. Secondly, we provide descriptive and injunctive
feedback in the form of emoticons after Schultz [17] to reduce
the possibility of the ‘boomerang’ effect. Finally, we
provide easy access to energy saving tips which we hope will
provide householders with the means to lower their energy
consumption. The website also provides the user with views
of his electricity consumption in a context suited to his
experimental group for previous time periods; yesterday, last
week, and the whole of the study thus far.</p>
      <p>Initial results from the participants in the twenty-strong
second test indicate that the feedback is viewed as both
interesting and useful, and we look forward to reporting the results
of the full trial in the near future. Recruitment for the main
trial started in January, 2011, and we expect to present
results after the trial in the Autumn of that year.</p>
      <p>Novelty
The CHARM Energy Study differs from the work reviewed
above in the following ways. There have been studies
involving more people with monthly feedback on paper-based
bills [3], and studies involving small numbers of people with
weekly paper-based feedback [17]. We believe that ours is
the first study testing the social norm approach with frequent
automated data collection and feedback. Further, ours is the
first such study in the UK where there may be resistance to
the social norm approach [15].</p>
      <p>Conclusion
It is planned [19] that all UK homes will have Smart Meters
installed by 2020, and the EU Smart Meter market has been
predicted [16] to be worth 25 Billion Dollars US in the ten
years from 2010 to 2020. Although the emerging UK
standard [20] mandates that UK Smart Meters will provide
bidirectional communications and support in-house displays, we
are unaware that there is yet a standard for the type of
information that will be displayed to the consumer.</p>
      <p>If the study shows a real reduction in domestic electricity
use resulting from social feedback methods, we hope that we
may influence the emerging Smart Meter standard to provide
for this means of change.</p>
      <p>Acknowledgements
This work was partly funded by the Engineering and
Physical Sciences Research Council (EPSRC) and is one of a
series of projects operating under the Research Councils UK
(RCUK) ‘Digital Economy’ Programme. Data transmission
costs have been subsidised by the UK M2M provider,
Wyless Plc in partnership with UK mobile telephony provider,
O2.</p>
      <p>Towards Egocentric Fuel Efficiency Feedback</p>
      <p>Ian Oakley
Madeira Interactive Technologies Institute (M-ITI)</p>
      <p>Funchal, 9000-390, Portugal
{tiago, filipe, mscott, vassilis, ian}@m-iti.org
ABSTRACT
Motivated by anecdotal evidence, we hypothesize that
an egocentric approach is more appropriate and relevant
to providing fuel efficiency feedback than a systemic
approach. In this paper we describe a proposed study to
test this hypothesis, and present the design of a fuel
efficiency feedback system for public transit bus drivers.</p>
      <p>Author Keywords
Feedback systems, fuel efficiency, public transit bus drivers
ACM Classification Keywords
H5.m. Information Interfaces and Presentation (e.g.,
HCI): Miscellaneous
Introduction
In 2010 the public transport authority in Madeira,
Portugal, installed onboard electronic equipment that
gauged driving fuel efficiency by presenting the driver with
very simple feedback: 3 green lights progressively
suggested that efficiency was increasingly optimum, while
3 red lights progressively suggested that driving
efficiency was increasingly sub-optimal. The system was
intended to give drivers feedback on their driving and
to help them achieve optimal driving efficiency. The
result was negative: drivers complained to human
resources that the system constantly showed 3 red lights,
suggesting that their driving was bad. Human resources
complained to operations that the system was bad for
morale.</p>
      <p>In response, operations attempted to “calibrate” the
system by tweaking its thresholds. The result was that
the feedback became useless and largely inaccurate,
ultimately resulting in the abolishment of the system. In
our discussions with the transport authority, it became
clear that in addition to the misinterpretation of the
feedback by the professional drivers as a rating of their
driving, the mountainous terrain of Madeira caused
genuinely inefficient driving. There was simply no way to
avoid steep hills that took a significant toll on fuel
consumption, thereby skewing the feedback towards
inefficient driving. The attempts at calibrating the
sysCopyright c 2011 for the individual papers by the papers’ authors.
Copying permitted only f or private and academic purposes. This volume is
published and copyrighted by the editors of PINC2011.
tem failed because, effectively, the on-board equipment
measured pure fuel consumption which in turn was
intricately related to the steep terrain of the environment.</p>
      <p>On the other hand, drivers perceived the feedback as a
reflection of their skills.</p>
      <p>Our anecdotal experience with the public transport
authority’s feedback system caused us to hypothesize that
providing feedback on specific driver behaviour, as
opposed to overall fuel efficiency, may be a more
appropriate way for motivating driver behaviour change.
Adopting a systemic approach to this issue, we argue that
existing feedback mechanisms relating to efficiency
provide a view of the complete system, parts of which the
driver has simply no way of effecting (such as the steep
terrain). Hence we argue that efficiency feedback
focusing on parts of the system that the driver can
effect (such as acceleration) may result in more efficient
driving behaviour. We term this approach to feedback
egocentric.</p>
      <p>In this paper we describe a fuel efficiency reporting
and advisory system that takes advantage of the
multisensor and interactive nature of modern smart-phones
to present feedback to drivers. More specifically, we
are interested in deploying the system in public transit
buses to measure its effectiveness on positively
influencing drivers’ behavior. By continuously capturing
realtime sensor data, we can calculate the Vehicle Specific
Power (VSP), a surrogate variable that strongly
correlates with both fuel consumption and pollutant emission
levels, providing a systemic view of efficiency [11].
Crucially, we are able to manipulate the calculation of VSP
to ignore environment variables and provide egocentric
feedback. Taking advantage of this manipulation, we
propose a study where we intend to test our
hypothesis about the benefits of egocentric over systemic
feedback. We believe that through the use of our system we
can promote not only short-term but also
medium/longterm positive changes in public transit bus drivers’
behaviours.</p>
      <p>
        Related Work
Research suggests that it is possible to achieve up to
15% of fuel consumption decrease when appropriate
driving behavior is used [
        <xref ref-type="bibr" rid="ref2">2, 6–8, 12</xref>
        ]. Independent of
contextual settings, appropriate driving behavior is
characterized by a combination of two main factors: speed and
acceleration. Specifically, it is believed that smoothness
of driving (i.e. slow acceleration levels) has a
considerable effect on fuel consumption. Therefore, fuel
efficiency systems should be dedicated to promoting
adequate driver feedback in relation to these two
essential factors, i.e., reasonable speeds and low
acceleration/deceleration levels. Accurately accounting for all
factors that influence fuel consumption and consequent
pollutant emissions can be a complex exercise.
Nevertheless, And &amp; Fwa present a possible vehicular fuel
consumption explanatory framework [1]: Physical
characteristics of the vehicle; vehicle usage and route
characteristics; road characteristics; and driver’s behavior.
      </p>
      <p>Of these factors, engine efficiency (physical
characteristics of the vehicle) is considered the most important [4].</p>
      <p>Still, the driver’s attitude and behavior towards the
maneuvering of the vehicle can considerably impact fuel
consumption levels. Therefore, it is commonly argued
that smoothness of driving leads to higher efficiency of
fuel consumption.</p>
      <p>Raw fuel consumption levels and pollutant emissions
can be calculated through the use of Portable
Emissions Measurement Systems (PEMS). These are
connected to vehicles through their On-Board Diagnostic
(OBD) interface, letting the PEMS system access the
vehicle’s on-board computer and calculate multiple
parameters [13]. Still, PEMS systems work primarily as
a diagnostic/analysis tool, not as a feedback support
mechanism. Furthermore, PEMS systems fail to reflect
contextual characteristics such as road gradient values.</p>
      <p>It is common to augment PEMS with GPS for analysis
purposes [13].</p>
      <p>The Vehicle Specific Power (VSP) approach is used to
approximate and predict actual emissions levels and fuel
consumptions [10, 11]. VSP is a model that tries to
explain consumption and emission levels from a physical
perspective; it corresponds to the Power Demand or
Vehicle Engine Load values, therefore correlating strongly
with fuel consumption and pollutant emission levels [13].</p>
      <p>The VSP model depends on three variable factors: speed,
acceleration, and road grade. Through the combination
of these factors, along with vehicle specific air and roll
resistance coefficients, VSP values are calculated as
follows [11]:</p>
      <p>V SP = v ∗ (a + g ∗ sin(ϕ) + rcoef ) + acoef ∗ v3 (1)
where v is speed in m/s, a is acceleration in m/s2, g is
9.807 m/s2, ϕ is the road gradient value, rcoef is the
rolling resistance term coefficient, and acoef is the air
drag term coefficient. Another characteristic of VSP
is its ability to support payload modeling, especially
important in situations where this value has noticeable
impact, such as is the case with public transit buses
[11]. Still, VSP does require that we calibrate the model
for each type of vehicle, as it is necessary to obtain
the ground truth for fuel consumption and pollutant
emission levels for the model to be effective.</p>
      <p>Devices such as smart-phones possess a wide variety of
sensors, like GPS and accelerometers, that enable
calculation of vehicle dynamics and consequently VSP values.</p>
      <p>It is then possible to approximate fuel consumption
using solely internal smart-phone sensors. These devices
can be easily incorporated into vehicles, and their
ability to provide a rich and extensible interaction platform
make them a feasible alternative mechanism to provide
drivers with fuel efficiency feedback. Furthermore, and
comparing with usual commercial systems such as
Scania Fuel-Saving Driver Support System1, smart-phones
are not restricted to specific vehicles, and can even be
device independent, which is the case when using
development platforms such as Google’s Android.</p>
      <p>Receiving timely feedback is key to motivating behaviour
change, people need to be aware of their behaviour in
order to change it. Fischer found the most successful
feedback was given frequently, clearly presented, used
computerised tools and allowed historic or normative
comparisons [9]. Our mobile interface reflects these types of
feedback. Utilising a mobile display allows frequent
opportunities for self-reflection and should increase driver
awareness of their behaviour.</p>
      <p>Consolvo, McDonald, and Landay [3] suggest a
number of design strategies for persuasive technologies that
wish to motivate behaviour change. These strategies
are based on psychological theories and recent
persuasive technology research and we have chosen to follow
some of their guidelines.</p>
      <p>First, we make use of abstractions rather than counting
solely on raw data to display to drivers. Secondly, the
data shown should be unobtrusive. This is of paramount
importance for safety reasons, as we need the mobile
display to support ignorability and not distract the driver
unnecessarily. Thirdly, since the data is to be presented
in public, we need to present it in a way that the driver
will not feel uncomfortable if others are aware of it.</p>
      <p>Fourthly, we decided to ensure that only positive
feedback is given, not punishing any “bad” behavior.
Concretely, we aim at rewarding possible low consumption
levels, but not use punishment for poor performance.</p>
      <p>This decision is supported by the notion that positive
feedback can indeed increase intrisic motivation by
affirming competence [5]. The anecdotal evidence from
the use of a commercial system by the public transit
company also supports this notion. Finally, we have
chosen to provide historical feedback. Doing so allows
the driver to reflect on past behaviours in order to make
more informed decisions on current behaviour.</p>
      <p>Research Methodology
We propose an experimental approach to study to what
extent we can, through the use of egocentric feedback,
1http://www.scania.com/media/featurestories/sustainability/every-drop-of-fuel-counts.aspx</p>
      <p>VSP
egoVSP
influence public transit bus drivers driving behavior. In
our study we are interested in the following research
questions:
• Can we accurately establish driving behavior profiles</p>
      <p>for bus drivers through the use of VSP calculations?
• To which extent can we positively influence driving
behavior through the use of egocentric feedback
techniques?
• Is the use of real-time more effective than the use
of historic feedback, or is a combination of the two
approaches most effective?
Consequently, and based on the previous mentioned
research questions, we raised the following hypotheses:
• H1. The use of the VSP surrogate variable (and its
derivatives) allows for accurate driving profile
characterisation
• H2. The use of egocentric driver feedback improves</p>
      <p>average fuel consumption levels
• H3. The use of real-time feedback does not
signifi</p>
      <p>cantly influence driving behavior
To test these hypotheses we propose to develop an
Android based software to continuously collect sensor
information so that trip instantaneous parameters, such
as speed and acceleration, can be calculated. We will
also consider the use of additional variable(s) to model
the influence of passenger payload on the overall vehicle
weight. Then, we intend to install equipment on-board
public transit buses and calibrate the VSP model. The
ground truth establishment of instantaneous fuel
consumption levels is a necessary condition for the success
of the VSP model. This may be achieved through the
use of a PEMS system or a similar mechanism.
Subsequently, we will develop a derivative of VSP called
egoVSP, which ignores road gradient and is defined as
follows
egoV SP = v ∗ (a + rcoef ) + acoef ∗ v3
Terms of the equation are defined equally as in eq. 1.</p>
      <p>These two fuel efficiency models, VSP and egoVSP, are
one of the two variables we intend to manipulate in our
study. The other variable is the type of feedback to
provide: real-time versus historical. Table 1 shows the
possible combinations of these two variables.</p>
      <p>Ongoing Work
As it stands, the system is a working prototype.
Targeted mainly at public transit bus drivers, the system</p>
      <p>RawInput
Sensor
Data</p>
      <p>Real-time Processing</p>
      <p>Pipeline
. .</p>
      <p>CompNonent
Storage</p>
      <p>User
Interface
Real-time
feedback</p>
      <p>VSP Acc.
10l 50 0.5
Historical
feedback</p>
      <p>Driver
is flexible and extensible enough to provide support for
any kind of vehicle.</p>
      <p>An overview of the architectural design is seen in Fig.
1, where the mechanism that is used to produce the
final output to the driver is visible. Raw sensor data is
sampled at several times per second, before it is passed
to a real-time processing pipeline. This allows us to
execute tasks in parallel that may require some
computational complexity, therefore increasing system
overall speed and responsiveness. The advantage of such a
scheme becomes more evident when, for example, the
system is required to perform continuous sensor data
integration by means of a Kalman Filter.</p>
      <p>The calculation of the vehicle dynamics and the VSP
modeling is also included in the processing pipeline.
After exiting the pipeline, the transformed output is then
fed to the feedback mechanism, which transmits
specific information to the driver, according to the type
of feedback used. All data is continuously stored in a
local database, so that further off-line analysis may be
performed. Repeated sampling from sensors will
undoubtedly drain the battery in its full in a matter of
hours, so there is the need of ensuring that the device
is fed continuous power by connecting it to the vehicle’s
internal electric circuit.</p>
      <p>Drivers initiate interaction through the system’s main
menu (see Fig. 2). In order to use the system, drivers
must register themselves before receiving a 3 digit PIN
code that uniquely identifies them. Vehicles registration
and VSP model calibration is also required to be
performed, but this may be done by the developers before
the system is made available to the drivers. This will
be the case when doing the experimental study with the
public transit bus drivers. Besides the VSP model
calibration, it is also possible to calibrate both the device
accelerometer, as well set up the desired orientation of
the phone inside the vehicle. This last step has some
limitations, as currently we are working with a phone
with only one accelerometer and no gyroscope, which
limits the phone’s orientation recognition. Just before
starting a trip, the driver introduces his PIN code and
indicates the vehicle that he is currently using. After
this the trip is marked as initiated.</p>
      <p>In order to test the effectiveness of the feedback system,
we propose using two different types of feedback:
realtime and historical. In the first, we will show a real-time
VSP graph that represents an approximation to the
actual VSP value. The graph is an abstract
representation, where it goes from green (low VSP values) to red
(high values) with an approximate quadratic function
increase. Additionally, actual fuel consumption, speed,
and acceleration values are to be represented.</p>
      <p>In regard to the historical feedback, our system will
make available two modes to the driver. The first will
show the distribution of time in the pre-defined VSP
bins, and the second will show a heat map of the route,
indicating VSP “hot zones”. The use of historical
feedback gives the driver a more broad perspective of his
driving behavior, as it recalls and identifies potential
patterns that may be improved. Furthermore,
historical feedback will only take place when the driver is not
actively driving.</p>
      <p>Conclusion
In this paper we have argued that egocentric feedback
on fuel efficiency can be more effective than systemic
feedback on motivating driving behaviour change.
Motivated by anecdotal evidence, we hypothesise that an
egocentric approach is more appropriate and relevant.</p>
      <p>By re-defining the VSP surrogate metric, we are able to
switch between systemic and egocentric feedback while
maintaining minimal changes between our
experimental conditions. Orthogonal to the manipulation of the
efficiency model, we describe our interest in testing the
effect of instantaneous versus historic data in the
feedback system.</p>
      <p>Acknowledgments
This work is supported by the Portuguese Foundation
for Science and Technology (FCT) grant CMU-PT/
HUMACH/ 004/ 2008 (SINAIS). This work is also
supported by the European Union project INTERVIR+
and the local public transit company, Horarios do
Funchal, S.A.
!"#$%&amp;'()*!++,-).+/&amp;,#)0#12'+,+(&amp;#3)0+)4#561#)0##')
!"#$%&amp;'()#!</p>
      <p>1%#',*2"#'
K%9102,%./0+,-12+#'0.3-'*).
80#9,-:#+;.'&lt;.E#-(#0L"1(.</p>
      <p>E#-(#0L"1(.</p>
      <p>E@M.ANN7.8C.</p>
      <p>EH?H!'P10G2:HO"1(H12H*I.
!
"#$%&amp;"'%!
/0.+"#:.)1),-.P,.)-,:,0+.10.'9,-9#,P.10%.#0#+#1$.P'-I.&lt;-'(.
1. -,:,1-2". )-'T,2+. 2-,1+#0L. U2''$V. ('O#$,. +,2"0'$'L#,:. +'.
,%*21+,. 10%. #0&lt;'-(. +,,01L,-:. #0. '-%,-. +'. -,%*2,. +",#-.
,0,-L;.*:,H.N,,01L,-:.1-,.1$-,1%;.O,2'(#0L.2'0:*(,-:.10%.</p>
      <p>P#$$. &lt;'-(. +",. 0,W+. L,0,-1+#'0. '&lt;. P'-I,-:7. "'(,'P0,-:7.
(101L,-:.10%.)'$#2;.(1I,-:X.1.$'0L#+*%#01$.2"10L,.#0.+",#-.
"1O#+:. 2'*$%. "19,. "*L,. #()12+H. 5'P,9,-7. #+. #:. 0'+'-#'*:$;.
%#&lt;&lt;#2*$+. +'. ,0L1L,. P#+". +,,01L,-:. 10%. ,&lt;&lt;,2+. 2"10L,:. #0.
+",#-. 1++#+*%,:. '-. 12+#'0:H. N,,01L,-:. 1-,. '&lt;+,0. (':+.
('+#91+,%. O;. +",#-. ),,-. L-'*). 10%. P"1+. #:. 2*--,0+$;. U2''$V.
'-. U*02''$VH. N",. 2"1$$,0L,:. '&lt;. +"#:. P'-I. 1-,. 0'+. '0$;. +",.
2-,1+#'0. '&lt;. ),-:*1:#9,. ('O#$,. +,2"0'$'L#,:. +'. ,02'*-1L,.
+,,01L,-:. +'. -,%*2,. +",#-. ,0,-L;. *:,7. O*+. +'. (1I,. +",:,.
+,2"0'$'L#,:. :*&lt;&lt;#2#,0+$;. U2''$V. +"1+. +",;. 1-,. %,:#-1O$,. 10%.
:'2#1$$;. 122,)+1O$,. ,0'*L". +'. :*))'-+. 1%')+#'0. 10%.
1))-')-#1+#'0. O;. +,,01L,-:H. /0. 1%%#+#'0. +'. )-'9#%#0L.
),-:'01$#:,%. 10%. 1LL-,L1+,. ,0,-L;. *:1L,. %1+1. 10%.
,%*21+#'01$. #0&lt;'-(1+#'0. #0. 1. (,10#0L&lt;*$. P1;7. +",. ('O#$,.
+,2"0'$'L#,:. P,. 1-,. %,:#L0#0L. P#$$. 1$$'P. &lt;'-. 1))-')-#1+#'0.
#0. U2''$V. P1;:. +",-,O;. &lt;':+,-#0L. 10. 12+#9,. 2'((*0#+;. '&lt;.
+,,01L,-:.P",-,.#+.#:.2''$.+'.(#0#(#:,.,0,-L;.*:,H..
"()*+,!-./0+,12!
B0,-L;.8:,7.N,,01L,-:7.Y'O#$,.N,2"0'$'L#,:..</p>
      <p>3/4"#5'6/*''
D,)1-+(,0+.'&lt;.!'()*+,-.Q2#,02,.</p>
      <p>QP10:,1.80#9,-:#+;.</p>
      <p>Q#0L$,+'0.&gt;1-I.</p>
      <p>QP10:,1.QKA.R&gt;&gt;7.8C.</p>
      <p>SH3*'G:P10:,1H12H*I.
!
"'3!'452267685)6+9!-./0+,12!
5MH(H. /0&lt;'-(1+#'0. #0+,-&lt;12,:. 10%. )-,:,0+1+#'0. 4,HLH7. 5!/6Z.</p>
      <p>Y#:2,$$10,'*:H..
:;%&amp;&lt;=&gt;'%:&lt;;!
3'9,-0(,0+:. 12-'::. +",. P'-$%. 1-,. 0'P. 2'((#++,%. +'.
-,%*2#0L.![A.,(#::#'0:.10%.'0,.I,;.1-,1.&lt;'-.#()-'9,(,0+.
#:.-,%*2+#'0.#0.%'(,:+#2.10%.),-:'01$.+-10:)'-+1+#'0.,0,-L;.
*:1L,H. /0. +",. "'(,. ![A. #:. -,$,1:,%. )-#(1-#$;. #0. +",.</p>
      <p>L,0,-1+#'0. '&lt;. ,$,2+-#2#+;7. +",. 2'(O*:+#'0. '&lt;. L1:. 10%. '#$. &lt;'-.
",1+#0L.10%.2'(O*:+#'0.'&lt;.&lt;*,$.#0.+-10:)'-+H.\#+"#0.+",.)1:+.</p>
      <p>A].;,1-:.+",-,."1:.O,,0.1.:+,1%;.#02-,1:,.#0.+",.0*(O,-.'&lt;.
1))$#102,:.#0.+",.('%,-0."'(,.2'*)$,%.P#+".L-'P+".#0.+",.
'P0,-:"#). '&lt;. ,0,-L;. "*0L-;. %,9#2,:. :*2". 1:. +*(O$,. %-#,-:.
10%.)$1:(1.N^:.10%.10.#02-,1:,.#0.+",.*:,.'&lt;.%,9#2,:.P#+".
:+10%O;. &lt;12#$#+#,:. _M`H. Y10;. '&lt;. +",. ,$,2+-#21$. %,9#2,:.
2'0+-#O*+#0L. +'. +",. -#:,. #0. %'(,:+#2. ,0,-L;. 1-,. *:,%. 10%.
:'(,+#(,:. 'P0,%. O;. +,,01L,-:H. ?,:,1-2". #0. +",. 8C. "1:.
#0%#21+,%.+"1+.aMb.'&lt;.+,,01L,-:."1%.1.N^7.(*:#2.:;:+,(.'-.
)"'0,.#0.+",#-.-''(:7.P#+".+P'.+"#-%:."19#0L.1$$.+"-,,._@c`H.</p>
      <p>K.:,)1-1+,.:+*%;.-,)'-+,%.+"1+.d]].:*-9,;,%.+,,01L,-:.1L,%.
@c. +'@a. P,-,. 2'$$,2+#9,$;. P1:+#0L. ,0'*L". ,0,-L;. +'. )'P,-.
d7e]A. :2"''$:. 10%. 1. +"#-%. '&lt;. +",. ,0,-L;. O,#0L. *:,%. P1:. 1.
%#-,2+.2'0:,f*,02,.'&lt;.U:+10%O;V.O,"19#'*-._@`H.
[*-. P'-I. '0. +",. U+1I#0L. '0. +",. +,,01L,-:V. )-'T,2+:.
4PPPH(1%d0-LH'-L6. P#$$. ,0L1L,. ;'*0L. ),')$,. 41L,%. @A&amp;
@a@6. #0. -,%*2#0L. +",#-. 'P0. ),-:'01$. ,0,-L;. *:,. 10%. (1I,.
............................................................
@./+.#:.)-'O$,(1+#2.-*00#0L.:+*%#,:.P#+".+,,01L,-:.&lt;-'(.1L,.
@d&amp;@M. #0. :2"''$:. #0. +",. 8C. P",0. +",;. O,L#0. )-,)1-#0L. &lt;'-.
3!QB. ,W1(#01+#'0:7. P,. +",-,&lt;'-,. 1$:'. +1-L,+. )-,&amp;+,,0:. +'.
,0:*-,. P,. 210. P'-I. +",. :1(,. :*OT,2+:. &lt;'-. +",. c. ;,1-.
%*-1+#'0.'&lt;.+",.)-'T,2+H.
!"#$%$&amp;'( )*+,-'#( $,( +%%$%./'#( %"0+1/#( ','1-2( .#'( %*+%( 0$33(
3+#%( %*1".-*( +/.3%*""/4( 5*$#( 0$33( 6'( +)*$'&amp;'/( %*1".-*( %*'(
)1'+%$",( "7( 8"6$3'( %')*,"3"-$'#( 9)+33'/( :;&lt;=( :+&gt;'( ;(
&lt;$77'1',)'?(%"('/.)+%'(%'',#(+6".%()*"$)'#(%*'2()+,(8+&gt;'(%"(
1'/.)'( ','1-2( .#'( +,/( !1"&amp;$/'( 7''/6+)&gt;( ",( ','1-2( .#+-'4(
:"6$3'( %')*,"3"-$'#( 0$33( +3#"( 6'( .#'/( %"( -+%*'1( ','1-2(
.#+-'( $,7"18+%$",( %*1".-*( #'37@1'!"1%( +,/( #',#$,-(
%')*,"3"-$'#A( 7"1( 'B+8!3'( /'%')%$,-( 0*$)*( %1+,#!"1%(
8'%*"/#( +1'( 6'$,-( .#'/A( $,( +//$%$",( %"( 8"1'( .#.+3( ','1-2(
8",$%"1$,-( $,( %*'( *"8'4( 5*'#'( 8"6$3'( %')*,"3"-$'#( 0$33(
8+&gt;'( !'1#",+3$#'/( +,/( +--1'-+%'/( ','1-2( .#+-'(
$,7"18+%$",( +))'##$63'( $,( 8'+,$,-7.3( 0+2#( %"( ',+63'(
)"8!+1$#",( +,/( )"8!'%$%$",( 6'%0'',( !''1#( %"( 7"#%'1( +,(
+)%$&amp;'( )"88.,$%2( "7( %'',+-'1#( $,%'1'#%'/( $,( 1'/.)$,-(
','1-2( .#'4( 5*'( 8"6$3'( /'&amp;$)'#( 0$33( +3#"( 8+&gt;'( +&amp;+$3+63'(
#%+%.#( .!/+%'#( +6".%( $,/$&amp;$/.+3( ','1-2( .#'( +,/( !1"&amp;$/'(
%+1-'%'/('/.)+%$",+3(8+%'1$+3(%"(.#'1#4(
5*'( !"!.3+1$%2( "7( *"8'( ','1-2( 8",$%"1#( 71"8(
8+,.7+)%.1'1#( #.)*( +#( ;3'1%:'( 90004+3'1%8'4)"8?( +,/(
C.11',%( C"#%( 90004).11',%)"#%4)"8?A( +,/( #'1&amp;$)'#( #.)*( +#(
D""-3'( E"0'1:'%'1( 90004-""-3'4)"8F!"0'18'%'1?( 8'+,(
%*+%( 8",$%"1$,-( '3')%1$)$%2( .#'( $,( %*'( *"8'( $#( $,'B!',#$&amp;'(
+,/( .,)"8!3$)+%'/4( ( G"0'&amp;'1A( '&amp;',( 0*'1'( %*'( ','1-2(
)",#.8!%$",( $,7"18+%$",( $#( !1"&amp;$/'/A( %*'( &amp;$#.+3$H+%$",( "7(
%*$#( $,7"18+%$",( "7%',( )+,,"%( '+#$32( )"11'3+%'/( 0$%*(
)",#.8!%$",(6'*+&amp;$".1(IJK4(5*$#($#('$%*'1(6')+.#'(%*'(.,$%#(
"7( 8'+#.1'8',%( +1'( 1'3+%$&amp;'32( 8'+,$,-3'##( %"( .#'1#( "1( %*'(
$,7"18+%$",( $#( $11'3'&amp;+,%( %"( %*'$1( $,%'1'#%#( 9'4-4( )"#%(
$,7"18+%$",( 8+2( ,"%( 8'+,( 8.)*( 7"1( %'',+-'1#( 0*"( /"( ,"%(
!+2( %*'( 6$33#?4( L.1%*'18"1'( %*'1'( $#( +( )"88",( 3+)&gt;( "7(
+0+1','##(+6".%(%*'(+8".,%("7(','1-2()",#.8'/(62(/'&amp;$)'(
#$,(%*'(*"8'(+,/(','1-2@#+&amp;$,-("!%$",#(IMK4(
5*'( &gt;'2( )*+33',-'( "7( %*$#( 0"1&gt;( $#( ,"%( ",32( /'#$-,( *$-*32(
.#+63'( 8"6$3'( %')*,"3"-$'#( %"( !1"&amp;$/'( +))'##( %"( ','1-2(
.#+-'( $,7"18+%$",( !1'#',%'/( $,( +( 8'+,$,-7.3( 0+2( 7"1(
%'',+-'1#A(6.%(+3#"(%"(',#.1'(%*+%(%*'#'(%')*,"3"-$'#(%*+%(+1'(
#.77$)$',%32( N)""3O( %*+%( %*'2( +1'( /'#$1+63'( +,/( #")$+332(
+))'!%+63'4( G+&amp;$,-( )1'+%'/( /'&amp;$)'#( %*+%( +1'( .#'/( +,/(
.,/'1#%""/( 62( %*'( %'',#A( 0'( 0$33( %*',( .#'( +( 1+,-'( "7(
+!!1"+)*'#( %"( 3'+/( %"( 3",-@%'18( 6'*+&amp;$".1+3( 8"/$7$)+%$",4(
5"( +)*$'&amp;'( %*'#'( -"+3#( +( !+1%$)$!+%"12( +!!1"+)*( $#( .#'/(
0*$)*( $,&amp;"3&amp;'#( 0"1&gt;$,-( /$1')%32( 0$%*( 2".,-( !'"!3'( $,(
#)*""3#(%"()+112(".%(/'#$-,(+,/('&amp;+3.+%$",(#%./$'#4((
P'( ,"0( /$#).##( %*'( )*+33',-'( "7( N)""3O( +,/( ".1( $,$%$+3(
7$,/$,-#A( %*'( !'1#.+#$&amp;'( +#!')%#( "7( %*'( %')*,"3"-$'#( 0'( +1'(
)1'+%$,-A(+,/(%*'(%')*,"3"-$)+3()*+33',-'#(0'(7+)'4(P'(-$&amp;'(
+,("&amp;'1&amp;$'0("7(1'3+%'/(0"1&gt;(+,/(7$,$#*(0$%*(+(/$#).##$",("7(
&gt;'2($##.'#(+,/(7.%.1'(0"1&gt;4(
!"#$%"&amp;''#()#$*+$,%**'-$
P*$3'( %*'( 8'+,$,-( "7( N)""3O( *+#( 6'',( )",#$/'1'/A( 7"1(
'B+8!3'( IQRK( IQSKA( %*'1'( $#( ,"%( +( #$,-3'( .,$&amp;'1#+332(
+!!3$)+63'( /'7$,$%$",4( C""3( 8+2( 6'( +,%$@#")$+3( "1( $33$)$%A( $%(
8+2(6'('B!',#$&amp;'(+,/(*$-*32(/'#$1+63'A("1($%(8+2(1'!1'#',%(
$,,"&amp;+%$",( 9+,/( %*'#'( +1'( ,"%( 8.%.+332( 'B)3.#$&amp;'(
)+%'-"1$'#?4( T,( %*'( )+#'( "7( %'',+-'1#A( !''1( -1".!#( "7%',(
/'7$,'( %*'( +%%1$6.%'#( "7( )""3( +,/( 6'$,-( N)""3O( $#( "7%',(
'B%1'8'32($8!"1%+,%4(L1"8(#%./$'#("7('B$#%$,-(3$%'1+%.1'(+,/(
$,$%$+3( /'#$-,( #'##$",#( 0'( *+&amp;'( $/',%$7$'/( %*1''( 8+$,( 3'&amp;'3#(
"7()""3,'##($,(%*'()",%'B%("7(%'',+-'14(5*'(7$1#%A(+,/('+#$'#%(
%"(+)*$'&amp;'A($#(%*'()""3,'##(+##")$+%'/(0$%*(*+&amp;$,-(/'#$1+63'(
%*$,-#( %*+%( "%*'1#( +#!$1'( %"( 9#.)*( +#( 3+%'#%( %')*,"3"-2( "1(
)3"%*'#?A( %*'( #')",/( $#( )""3,'##( +##")$+%'/( 0$%*( +)%$",#( "1(
+)%$&amp;$%$'#( %*+%( -+$,( 1')"-,$%$",( 71"8( !''1#4( 5*'( %*$1/A( +,/(
8"#%( )*+33',-$,-( %"( +)*$'&amp;'A( $#( %*+%( "7( *"3$#%$)+332( N6'$,-O(
)""3( +,/( "7%',( 1'#.3%#( $,( 6'$,-( +/8$1'/( +,/( "7%',( /'7'11'/(
%"( 62( !''1#4( T%( $#( %*$#( 3+%%'1( )+%'-"12( %*+%( 8+1&gt;'%$,-(
)"8!+,$'#( "7%',( #''&gt;( %"( $,73.',)'( +#A( 62( &amp;$1%.'A( !1"/.)%#(
%*'2( +##")$+%'( 0$%*( 6')"8'( )""3( +,/( +1'( %*',( /'#$1+63'( 62(
"%*'1#4((
C""3,'##( $#( -','1+332( +( )*+33',-$,-( !1"!'1%2( %"( /'#$-,( $,%"(
+( !1"/.)%( +,/( 0$%*$,( %*'( %*1''( %2!'#( "7( )""3( 0'( *+&amp;'(
$/',%$72(%*'(#')",/(9+##")$+%'/(0$%*(+)%$",#("1(+)%$&amp;$%$'#(%*+%(
-+$,(1')"-,$%$",(71"8(!''1#?(+#(8"#%(3$&gt;'32(%"(6'(+)*$'&amp;+63'(
0$%*$,( %*'( !1"U')%4( 5*$#( 0$33( 6'( )".!3'/A( %"( +( 3'##'1( 'B%',%A(
0$%*( %*'( 7$1#%( %2!'( 9*+&amp;$,-( /'#$1+63'( %*$,-#?4( 5*'( 8"6$3'(
+!!3$)+%$",#( 0'( +1'( /'#$-,$,-( 0$33( ',+63'( %'',( .#'1#( %"(
8",$%"1( %*'$1( ','1-2( .#+-'( 9)+!%.1'/( .#$,-( 3"0( )"#%(
8",$%"1$,-(%')*,"3"-2($,(%*'(*"8'(+,/(8"6$3'(/'&amp;$)'#?(+,/(
/'&amp;$#'( %*'$1( "0,( 0+2#( "7( 1'!1'#',%$,-A( #*+1$,-( +,/(
)"8!+1$,-( %*'( $,7"18+%$",4( 5*1".-*( ".1( !+1%$)$!+%"12(
+!!1"+)*( 0'( 0$33( )1'+%'( +!!3$)+%$",#( %*+%( #.!!"1%(
).#%"8$#+%$",( +,/( 'B!1'##$&amp;$%2( #.)*( %*+%( %*'2( )+,( 6'(
+!!1"!1$+%'/( $,( +( N)""3O( 0+2#( 62( %'',+-'1#4( V,'( #)',+1$"(
0'( ',&amp;$#+-'( $#( %'',+-'1#( 6'$,-( +63'( %"( )"8!+1'( ','1-2(
.#+-'(.#$,-(+(8'%1$)(+,/(&amp;$#.+3$H+%$",(%*'2(%*'8#'3&amp;'#(*+&amp;'(
/'&amp;$#'/( +,/F"1( +/"!%'/( 90*$)*( $#( +##.8'/( %"( 6'( )""3( $,(
%*'$1(!''1(-1".!?(%"(/'%'18$,'(0*"($#(%*'(0$,,'1(9.#$,-(%*'(
3'+#%( ','1-2?( +,/( 0*"( $#( %*'( 3"#'1( 9.#$,-( %*'( 8"#%( ','1-2?4(
T,( %*$#( 'B+8!3'( $%( $#( 3$&gt;'32( %*+%( )"8!'%$%$",( 0$33( ',)".1+-'(
)",#$/'1+%$",( +,/( 1'/.)%$",( "7( ','1-2( .#'4( ;3#"A( %*'#'(
8"%$&amp;+%$",#( 0$33( 6'( ,.1%.1'/( +,/( #.!!"1%'/( %*1".-*( .#'( "7(
%*'( :;&lt;( %')*,"3"-$'#( %*+%( 0$33( !1"&amp;$/'( $,7"18+%$",( +,/(
+/&amp;$)'( ",( 8'+#.1'#( %"( 1'/.)'( ','1-2( .#'A( $,( +//$%$",( %"(
!1"&amp;$/$,-($,7"18+%$",(",().11',%(','1-2(.#+-'4((((
%"&amp;().()$/#"0.*12$$
5*$#( 0"1&gt;( 0$33( 6.$3/( .!",( %*'( 55:( 8"/'3( "7( 6'*+&amp;$".1(
)*+,-'( IQQK( +,/( 0$33( 3$,&gt;( $,%"( 8"1'( 1')',%( 0"1&gt;( ",(
'8"%$",+3(',-+-'8',%(7"1(6'*+&amp;$".1()*+,-'(9ISKAIWK?(0*$)*(
/'8",#%1+%'#( %*+%( 6'*+&amp;$".1( )*+,-'( $#( 8"1'( '77')%$&amp;'A(
',-+-$,-( +,/( !1"/.)%$&amp;'( $7( %*'1'( $#( +,( '8"%$",+3(
',-+-'8',%(6'%0'',(%*'(%')*,"3"-2(+,/(%*'(.#'14(5*.#(".1(
8"6$3'( %')*,"3"-$'#( *+&amp;'( %"( #.!!"1%( +!!1"!1$+%$",( $,( )""3(
0+2#( 6.%( +3#"( *+&amp;'( %"( 6'( /'#$-,'/( $,( +( 0+2( %*+%( %'',+-'1#(
)+,('+#$32(1'3+%'(%"(%*'8(+,/($,(+(8+,,'1(%*+%($#(1')'!%$&amp;'(%"(
'8"%$",+3($,%'1!1'%+%$",(9$4'4(%*'(#2#%'8#(%*'8#'3&amp;'#(/"(,"%(
,')'##+1$32( *+&amp;'( %"( 6'( '8"%$",+3A( %*'2( U.#%( *+&amp;'( %"( 6'( +63'(
%"( +!!'+1( '8"%$",+3( '&amp;',( $7( %*+%( '77')%( $#( !1"U')%'/( 62( %*'(
.#'1?4(
5*$#(!1"U')%(0"1&gt;#(71"8(%*'(+##.8!%$",(%*+%(%'',+-'1#(*+&amp;'(
%*'( !"%',%$+3( %"( 8+&gt;'( #$-,$7$)+,%( )*+,-'#( %"( ','1-2( .#+-'4(
X"%(",32()+,()*+,-$,-(%'',+-'(6'*+&amp;$".1(+77')%(%*'$1(3",-@
!"#$%&amp;"#'()*+%,'"-%.,!%!/"0%*#"%*+'(%1)%*%&amp;('1!1()%2/"#"%!/"0%
3*)%,'"%4&amp;"'!"#%&amp;(2"#5%!(%*66"3!%!/"%*!!1!,7"'%*)7%."/*81(,#'%
(6% !/"1#% &amp;*#")!'-% '1.+1)9'% *)7% 6#1")7':% ;'% $*)0% !"")*9"#'%
/*8"% *% 9#"*!"#% *$(,)!% (6% +"1',#"% !1$"% !/*)% *7,+!'-% !/1'% 3*)%
#"',+!% 1)% !/"% ,'"% (6% $*)0% /19/% ")"#90% !"3/)(+(91"'% ',3/% *'%
3($&amp;,!"#'-% 9*$"'% 3()'(+"'% *)7% ")!"#!*1)$")!% '0'!"$'-%
2/1+"% !/"1#% ."/*81(,#'% *#"% )(!% $()1!(#"7% .0% &amp;*#")!'% (#%
9,*#71*)'% 1)% !/"% 2*0% *% 0(,)9"#% 3/1+75'% *3!181!1"'% $19/!% .":%
&lt;/"% &amp;#(="3!% 21++% *1$% !(% 9*!/"#% $(#"% 1)6(#$*!1()% *.(,!%
!"")*9"#'5% &amp;*!!"#)'% (6% ")"#90% ,'"% 1)% (#7"#% !(% ,)7"#'!*)7%
!/"1#% ."/*81(,#'% *)7% $(!18*!1()'% $(#"-% *)7% /(2% !/"0% $*0%
."%1)6+,")3"7:%
&lt;/"% 1)1!1*+% 9(*+% 6(#% ."/*81(,#% 3/*)9"% 1)% !/1'% 2(#&gt;% 1)% !(%
1)6+,")3"% #"7,3!1()% 1)% "+"3!#13*+% *)7% !#*)'&amp;(#!% ")"#90% ,'":%
?)1!1*++0-% '!(#1"'% (6% ")"#90% ,'*9"% 21++% ."% 3(++"3!"7% 6#($%
!"")*9"#'% 1)% !/"% '3/((+'% 21!/% 2/13/% 2"% *#"% 2(#&gt;1)9:% &lt;/"%
'!(#1"'%21++%."%3($&amp;('"7%(6%!"@!-%1$*9"'-%817"(%(#%*,71(%*)7%
21++% 918"% A,*+1!*!18"% 1)'19/!'% 1)!(% !"")% ")"#90% ,'"% *)7%
*!!1!,7"'% !(2*#7'% ")"#90% ,'"% B'($"% 21++% ."% 3(++"3!"7% 1)%
'3/((+-% (!/"#'% 21++% ."% 3(++"3!"7% 7,#1)9% 6(3,'% 9#(,&amp;'C:% ;!% *%
+*!"#%'!*9"%1)%!/"%&amp;#(="3!-%*6!"#%2"%/*8"%7"&amp;+(0"7%!/"%D;EF%
*)7% D;EG% &amp;#(7,3!'-% 2"% 21++% !/")% 3(++"3!% ")"#90% '!(#1"'%
*9*1)% !(% *++(2% 6(#% A,*+1!*!18"% 3($&amp;*#1'()% (6% 3/*)9"% 1)%
."/*81(,#:%%
!""#$!"%&amp;#'(')*$$
&lt;/"%&amp;#(="3!%*1$'%!(%3#"*!"%!2(%&gt;"0%$(.1+"%&amp;#(7,3!'-%()"%6(#%
FHIFJ% 0"*#% (+7'% BD;EFC% *)7% *)(!/"#% 6(#% FJIFK% 0"*#% (+7'%
BD;EGC:%;%&gt;"0%1'',"%1'%'"+"3!1)9%2/13/%$(.1+"%&amp;+*!6(#$B'C%
!(% !*#9"!% *)7% !/1'% 1'% +1&gt;"+0% !(% ."% !/"% !#*7"I(66% 1)% !"#$'% (6%
6"*!,#"'% &amp;#(817"7% *)7% 7"813"% &amp;(&amp;,+*#1!0:% L/1+"% '$*#!%
&amp;/()"'% ',3/% *'% M+*3&gt;."##0% 7"813"'-% 1N/()"'-% ;)7#(17%
7"813"'-% *)7% O(&gt;1*% P0$.1*)% /*)7'"!'% *#"% 1)3#"*'1)9+0%
&amp;#"8*+")!% *$()9% *7,+!'% 1)% !/"% QR-% !/"1#% /19/% 3('!% (6!")%
$*&gt;"'% !/"$% 1)*33"''1.+"% !(% 0(,)9"#% !"")*9"#'% 21!/% +1!!+"%
'&amp;")71)9% &amp;(2"#% *)7% #"'!#13!"7% !(% 4&amp;*0% *'% 0(,% 9(5% B3()!#*3!%
6#""C% 3*++% &amp;+*)':% S#($% (,#% 3,##")!% '!,71"'% 1)% '3/((+'% 21!/%
0"*#%T'%B*9"%FUIFFC%*)7%0"*#%FU'%B*9"%FHIFVC%1!%1'%*&amp;&amp;*#")!%
!/*!% !/"% &amp;/()"'% !/"0% (2)% *#"% .*'13% 7"813"'% (6!")% /*)7"7%
7(2)% 6#($% *)% (+7"#% '1.+1)9% (#% &amp;*#")!:% L"% /*8"% *+'(% 6(,)7%
!/*!% !/"% 3/1+7#")% 1)% (,#% 1)1!1*+% '!,71"'% /*8"% +1!!+"% 1)!"#"'!% 1)%
(2)1)9% *)7% ,'1)9% *% $(.1+"% &amp;/()":% M(0'% 1)% &amp;*#!13,+*#%
*7$1!!"7%!/*!%!/"0%6*1+"7%!(%#"$"$."#%!(%3/*#9"%!/"1#%&amp;/()"%
(#%")',#"%!/"0%/*7%")(,9/%3#"71!%!(%$*&gt;"%3*++':%P"8"#*+%0"*#%
FU% .(0'% 3+*1$"7% !/*!% !/"0% 6(,)7% !/"1#% $(.1+"% &amp;/()"% ,'"6,+%
*'%*)%*+*#$%3+(3&gt;%.,!%+1!!+"%"+'":%%
&lt;"3/)(+(91"'% *7(&amp;!"7% .0% (+7"#% !"")*9"#'% BFTIFKC% 21!/%
'+19/!+0% /19/% '&amp;")71)9% &amp;(2"#% *#"% (6!")% 6*'/1()% +"7-% .,!% )(!%
)"3"''*#1+0% !/('"% 2/13/% /1!% !/"% $*1)'!#"*$% (#% *7,+!% $"71*:%
S(#%"@*$&amp;+"-%1)%*%',#8"0%(6%*++%)"2%,)7"#9#*7,*!"%")!#*)!'%
!(%*%$*=(#%QR%Q)18"#'1!0-%M+*3&gt;."##0%7"813"'%(,!),$."#"7%
.(!/%O(&gt;1*5'%*)7%1N/()"'-%6(#%"@*$&amp;+":%&lt;/1'%1'%&amp;*#!+0%7,"%!(%
!/"%3('!%(6%',3/%7"813"'%.,!%*+'(%!/"%*8*1+*.1+1!0%(6%'&amp;"31613%
3($$,)13*!1()% 3/*))"+'% W% M+*3&gt;."##0% D"''")9"#% ."1)9% *%
&amp;(&amp;,+*#% ()"-% .,!% )(!% B"*'1+0C% *33"''1.+"% 21!/(,!% *%
M+*3&gt;."##0% /*)7'"!:% L1!/1)% !/"% &amp;#(="3!% 2"% /*8"% 6,)7'% !(%
&amp;#(817"%*%'$*++%),$."#%(6%&amp;*#!131&amp;*)!'%21!/%$(.1+"%7"813"'%
B!/"%),$."#%7"&amp;")71)9%()%!/"%3('!%(6%!/"%7"813"C-%.,!%*6!"#%
1)1!1*+% !#1*+'% 2"% 21'/% !(% (&amp;")% !/"% '0'!"$% ,&amp;% !(% *'% 217"#%
&amp;*#!131&amp;*!1()%*'%&amp;(''1.+":%%%
?)% (#7"#% !(% ")*.+"% ")"#90% $()1!(#1)9% 1)% !/"% /($"% !/"%
&amp;#(="3!% 21++% ,'"% +(2% 3('!% XY&lt;P% /($"% ")"#90% '")'1)9%
!"3/)(+(91"'% 6#($% $*),6*3!,#"#'% ',3/% *'% ;+"#!D"% *)7%
X,##")!% X('!% !/*!% 3*)% '")'"% "+"3!#13*+% ")"#90% ,'"% ()% *% &amp;"#I
/($"% *)7% &amp;"#I*&amp;&amp;+1*)3"% 9#*),+*#1!0-% *)7% $*&gt;"% 1!% *8*1+*.+"%
(8"#% !/"% ?)!"#)"!:% P")'1)9% &gt;1!'% 21++% ."% &amp;#(817"7% 6(#% *%
),$."#%(6%,'"#%43/*$&amp;1()'5%*)7%1'%/(&amp;"7%!/*!%!/"0%21++%/"+&amp;%
")3(,#*9"% (!/"#% !"")'% !(% &amp;"'!"#% &amp;*#")!'% 1)!(% .,01)9% !/"% &gt;1!%
'(%!/"0%3*)%!*&gt;"%&amp;*#!:%%
;%&amp;*#!131&amp;*!(#0%7"'19)%&amp;#(3"''%!(%3#"*!"%D;EF%*)7%D;EG%
21++% ."% ()9(1)9% 21!/% '"8"#*+% 7166"#")!% 9#(,&amp;'% 1)% !"")*9"#'%
1)%'3/((+'%*3#(''%!/"%QR%1)8(+8"7:%%L"%"@&amp;"3!%!(%7"8"+(&amp;%*%
$1@!,#"% (6% "7,3*!1()-% 9*$"I&amp;+*01)9% *)7% 3($&amp;"!1!1()-%
3(++*.(#*!1()-% &amp;""#% &amp;#"'',#"% *)7% '"+6I*2*#")"''% #*1'1)9%
*&amp;&amp;#(*3/"'% 21!/1)% *)7% *#(,)7% !/"'"% &amp;#(7,3!'% !(% +"*7% !(%
#"7,3!1()%1)%&amp;"#'()*+%")"#90%,'"%1)%!/"%'/(#!%!"#$%*)7%+()9I
!"#$%."/*81(,#*+%3/*)9":%?)%*771!1()%!(%D;EF%*)7%D;EG-%
*%'&amp;"31*++0%7"'19)"7%2".%&amp;(#!*+%21++%."%,'"7%!/#(,9/(,!%!/"%
&amp;#(="3!% !(% *++(2% &amp;*#!131&amp;*)!'% 1)% !/"% &amp;#(="3!% !(% '/*#"% '!(#1"'%
*.(,!%!/"1#%")"#90%,'*9"-%,'1)9%)*##*!18"-%1$*9"'%*)7%817"(:%
&lt;/"'"% 21++% &amp;#(817"% *% #13/% '(,#3"% (6% A,*+1!*!18"% 7*!*% 6(#% !/"%
&amp;#(="3!%*)7%*+'(%*++(2%!/"%17")!1613*!1()%(6%3/*)9"%1)%")"#90%
,'*9"%/*.1!'%*'%!/"%&amp;#(="3!%&amp;#(9#"''"':%%%%%
+"(,!"-$.'+/$
;% '$*++% ),$."#% (6% 2"*#*.+"Z$(.1+"% #"'"*#3/% &amp;#(!(!0&amp;"'%
*)7% &amp;#(7,3!'% /*8"% ."")% 7"8"+(&amp;"7% 6(#% 3()8"01)9% ")"#90%
,'*9"% 1)6(#$*!1():% Q.1[#"")% \T]% ,'"7% $(.1+"% &amp;/()"'% *'%
*$.1")!% 71'&amp;+*0'% !(% 918"% ,'"#% 6""7.*3&gt;% ()% !/"1#%
!#*)'&amp;(#!*!1()%."/*81(,#':%?!%#"+1"7%()%!/"%2"*#*.+"%'")'1)9%
,)1!-%[PD%3"++%'19)*+'%*)7%!/"%&amp;*#!131&amp;*)!'5%$*),*+%1)&amp;,!%!(%
7"!"3!% !#*)'&amp;(#!*!1()% $(7":% ^3(I6#1")7+0% !#*)'&amp;(#!*!1()%
."/*81(,#'-% ',3/% *'% 3*#&amp;((+1)9-% !*&gt;1)9% .,'% *)7% 303+1)9% "!3:%
2"#"% ")3(,#*9"7% *)7% '/(2)% *'% #"2*#7'% ()% !/"% *$.1")!%
71'&amp;+*0:%^)"#90_16"%\H]%1'%*%&amp;"#8*'18"%'")'1)9%*)7%6""7.*3&gt;%
'0'!"$:% ;% '"#8"#% 2*'% 3())"3!"7% 21#"+"''+0% 81*% *% .*'"%
'!*!1()%!(%")"#90%'")'(#'%2/13/%#"&amp;(#!"7%!/"1#%")"#90%,'*9"%
"8"#0% 3(,&amp;+"% $1),!"':% &lt;/"% #"*+% !1$"% ")"#90% 3()',$&amp;!1()%
1)6(#$*!1()% !(9"!/"#% 21!/% 7"813"% 3()',$&amp;!1()% /1'!(#0-%
")"#90%#"'"#8*!1()%!1&amp;'%"!3:%2"#"%7"+18"#"7%!(%*%'$*#!%&amp;/()"%
,&amp;()% ,'"#`'% #"A,"'!% ,'1)9% *% X*#(,'"+% 1)!"#6*3":% [#17X*#.()%
1'% *)% 1N/()"% *&amp;&amp;% &amp;#(7,3"7% !/#(,9/% !/"% 1E^*P% N#(="3!%
B222:17"*'&amp;#(="3!:1)6(C% 2/13/% '/(2'% !/"% 3,##")!% 3*#.()%
1)!")'1!0-% !/"% A,*)!1!0% (6% XYG% &amp;#(7,3"7% 6(#% F% &gt;L/% (6%
"+"3!#131!0% 3()',$"7-% (6% !/"% "+"3!#131!0% 3,##")!+0% ."1)9%
9")"#*!"7%1)%!/"%QR:%&lt;/"%1)!")!1()%(6%!/"%*&amp;&amp;%1'%!/*!%1!%3*)%
."% ,'"7% *'% *% !((+% !(% 1)6+,")3"% ")"#90% 7"$*)7% *)7% #"7,3"%
XYG% "$1''1()':% ;+"#!D"% &amp;#(817"% *)% 1N/()"% *&amp;&amp;% !(% *++(2%
#"$(!"% *33"''% !(% 7*!*% #"3(#7"7% .0% !/"1#% /($"% ")"#90%
$()1!(#1)9%&amp;#(7,3!:%&lt;/"%*&amp;&amp;%*++(2'%3,##")!%")"#90%,'*9"%!(%
."%81"2"7%#"$(!"+0%*)7%&amp;#(817"'%*%4&amp;"#'()*+%'21)9($"!"#5%
2/13/% 1'% *% '1$&amp;+"% 9#*&amp;/13*+% #"&amp;#"'")!*!1()% !(% /"+&amp;% 3()8"0%
")"#90% ,'*9"% 1)% *)% "*'1+0% ,)7"#'!*)7*.+"% $*))"#:% L/1+"%
!/"'"% "@*$&amp;+"'% /19/+19/!% '($"% 1))(8*!18"% *&amp;&amp;#(*3/"'% !(%
!"#$%&amp;'() "'"!(*) $+") ,-.$(-) /.0&amp;1") ,"%-'.1.(&amp;"+) '.'") .2)
,-"/) 31&amp;(') 4&amp;,-) ,-") /.!") -.1&amp;+,&amp;%) 3'#) 1.'(5,"!/) "'"!(*)
!"#$%,&amp;.')3&amp;/+).2),-&amp;+)4.!67))
!"#$%##"&amp;'(
8')%!"3,&amp;'()"'"!(*)+39&amp;'()#"9&amp;%"+)2.!),""'3("!+)4")%.'+&amp;#"!)
,-3,) :%..1;) &amp;+) 3) &lt;.4"!2$1) 23%,.!) &amp;') /.,&amp;93,&amp;'() 3#.&lt;,&amp;.') 3'#)
3&lt;&lt;!.&lt;!&amp;3,&amp;.'7) ) =.) /36") "'"!(*) +39&amp;'() 3,,!3%,&amp;9"&gt;) 4") '""#)
,.) ,3&lt;) &amp;',.) ,-") &lt;.,"',&amp;31) 2.!) &lt;""!) &lt;!"++$!"&gt;) &lt;"!+.'31) (.31)
+",,&amp;'() 3'#) 3%-&amp;"9"/"',&gt;) 3'#) /36") (..#) $+") .2) "'"!(*) 3')
&amp;',"(!31) &lt;3!,) .2) ,-") ("'"!31) #&amp;+%.$!+") 0",4""') ,""'+7) ?$!)
3&lt;&lt;!.3%-)&amp;+) '.,),.)3,,"/&lt;,),.)&lt;!.#$%")%..1)&lt;!.#$%,+)&lt;"!)+"&gt;)
0$,) ,.) %!"3,") ,"%-'.1.(&amp;"+) ,-3,) %3') 0") &lt;"!+.'31&amp;+"#) 3'#)
3&lt;&lt;!.&lt;!&amp;3,"#)&amp;')%..1)43*+7)
=-") ",-&amp;%+) .2) &lt;"!+$3+&amp;.') @AB) &amp;') ,-") %.',"C,) .2) ,-&amp;+) &lt;!.D"%,)
3!") +./"4-3,) /&amp;,&amp;(3,"#) &amp;') ,-3,) ,-") !"#$%,&amp;.') .2) "'"!(*) $+")
&amp;+) 3%%"&lt;,"#) ,.) 0") 3) '"%"++3!*) /.9"7) E.4"9"!&gt;) ,-&amp;+) 4&amp;11) 0")
3') 3!"3) 4") "C&lt;1.!") &amp;') #",3&amp;1) 3+) ,-") #"9"1.&lt;/"',) .2) ,-")
FGHI) 3'#) FGHJ) &lt;!.,.,*&lt;"+) &lt;!.(!"++7) ) =-") &lt;!.D"%,) &amp;+)
%$!!"',1*) "'(3("#) &amp;') #"+&amp;(') +"++&amp;.'+) 4&amp;,-) ,""'3("!+) ,.)
"C&lt;1.!") &amp;'&amp;,&amp;31) +%"'3!&amp;.+) 3'#) !"K$&amp;!"/"',+) 2.!) FGHI) 3'#)
2$!,-"!) $'#"!+,3'#) ,-") 6"*) %-3!3%,"!&amp;+,&amp;%+) .2) %..1) 2.!)
#&amp;22"!"',) (!.$&lt;+7) 8') &lt;3!311"1) 4") 3!") 31+.) "C&lt;1.!&amp;'() 3'#)
,"%-'&amp;%31) &lt;.++&amp;0&amp;1&amp;,&amp;"+) 3'#) "C&lt;"!,) ,"%-'&amp;%31) #"+&amp;('+&gt;) 3'#)
&amp;'9"+,&amp;(3,&amp;'() ,""'3("!+;) %$!!"',) 3,,&amp;,$#"+) ,.43!#+) "'"!(*)
$+"7)L")-.&lt;"),-3,),-")'.9"1),-"/"+)&amp;'),-&amp;+)4.!6)4&amp;11)0").2)
&amp;',"!"+,) ,.) ,-") &lt;3!,&amp;%&amp;&lt;3',+) .2) ,-") 4.!6+-.&lt;) 3'#) &lt;!.9.6")
&amp;',"!"+,&amp;'()#&amp;+%$++&amp;.'7))
)$*'&amp;+,-!./-'0#(
L") 4.$1#) 1&amp;6") ,.) ,-3'6) MNOPQ) R$'#"!) ,-") H&amp;(&amp;,31)
M%.'./*)3'#)M'"!(*)N!.(!3//"S)2.!)2$'#&amp;'(),-&amp;+)4.!67)))!
1-2-1-'$-#(
@IB) TTQ) U"4+) RJVVWS) =""'3("!+) 3!") :+,3'#0*) 9&amp;113&amp;'+;7)</p>
      <p>P",!&amp;"9"#) 2!./)
-,,&lt;XYY'"4+700%7%.7$6YIY-&amp;Y+%.,13'#YWJIZAWJ7+,/)</p>
      <p>R3%%"++"#)[3'$3!*)JVIIS7)
@JB) T"31"&gt;) P7) 3'#) Q!""#&gt;) Q7) G22"%,&amp;9") 8',"!3%,&amp;.'X) E.4)
"/.,&amp;.'31) 3("',+) 322"%,) $+"!+7) 8',"!'3,&amp;.'31) [.$!'31) .2)</p>
      <p>E$/3'5Q./&lt;$,"!)O,$#&amp;"+&gt;)W\)RZS7)\]]5\\W&gt;)JVVZ7)
@^B))Q-!&amp;+,."!) G7) TD.!6+6.(&gt;) _&amp;$1&amp;.) [3%$%%&amp;&gt;) `$%&amp;3'.)
_3/0"!&amp;'&amp;&gt;) =3,$) U&amp;"/&amp;'"'&gt;=.&lt;&amp;) F&amp;66.13&gt;) Q3!&amp;')
=.!+,"'++.'&gt;) 3'#) F3++&amp;/.) T"!,.'%&amp;'&amp;&gt;) aM'"!(*1&amp;2"X)
&lt;"!93+&amp;9") "'"!(*) 343!"'"++) 2.!) -.$+"-.1#+&gt;b) &amp;')
N!.%""#&amp;'(+) .2) ,-") IJ,-) GQF) &amp;',"!'3,&amp;.'31) %.'2"!"'%")
3#D$'%,) &lt;3&lt;"!+) .') c0&amp;K$&amp;,.$+) %./&lt;$,&amp;'(&gt;) c0&amp;%./&lt;) dIV&gt;)
&lt;&lt;7)^WI5^WJ&gt;)JVIV7)
)
)
)
)
)
)
@eB) Q!""#&gt;) Q7) 3'#) T"31"&gt;) P7&gt;) M'(3(&amp;'() MC&lt;"!&amp;"'%"+) 4&amp;,-)</p>
      <p>M/.,&amp;.'31) f&amp;!,$31) =-"!3&lt;&amp;+,+7) &amp;') 8',"!'3,&amp;.'31) H"+&amp;(')
3'#)M'(3(30&amp;1&amp;,*)Q.'2"!"'%")g)U.!#&amp;QE8&gt;)?+1.&gt;)JVVW7)
@]B) H"&lt;3!,/"',) .2) M'"!(*) h) Q1&amp;/3,") Q-3'(") RJVVZS)</p>
      <p>M'"!(*)Q.'+$/&lt;,&amp;.')&amp;'),-")c'&amp;,"#)i&amp;'(#./7)P",!&amp;"9"#)
2!./)
-,,&lt;XYY4447#"%%7(.97$6Y"'Y%.',"',Y%/+Y+,3,&amp;+,&amp;%+Y&lt;$01&amp;%
3,&amp;.'+Y"%$6)Y"%$673+&lt;C)R3%%"++"#)[3'$3!*)JVIIS7)
@WB) [3/"+) N&amp;"!%"&gt;) H&amp;3'") [7) O%-&amp;3'.&gt;) 3'#) M!&amp;%) N3$1.+&gt;)
aE./"&gt;) -30&amp;,+&gt;) 3'#) "'"!(*X) "C3/&amp;'&amp;'() #./"+,&amp;%)
&amp;',"!3%,&amp;.'+) 3'#) "'"!(*) %.'+$/&lt;,&amp;.'&gt;b) &amp;') QE8dIVX)
N!.%""#&amp;'(+) .2) ,-") JA,-) &amp;',"!'3,&amp;.'31) %.'2"!"'%") .')
E$/3') 23%,.!+) &amp;') %./&lt;$,&amp;'() +*+,"/+&gt;) U"4) j.!6&gt;) Uj&gt;)
cOG&gt;)&lt;&lt;7)IZA]5IZZe&gt;)GQF&gt;)JVIV7)
@\B) [.') k!."-1&amp;%-&gt;) =343''3) H&amp;113-$',&gt;) N!"#!3() i13+'D3&gt;)
["''&amp;2"!) F3'6.&gt;) O$''*) Q.'+.19.&gt;) T"9"!1*) E3!!&amp;+.'&gt;)
3'#)[3/"+)G7)`3'#3*&gt;)ac0&amp;(!""'X)&amp;'9"+,&amp;(3,&amp;'()3)/.0&amp;1")
,..1) 2.!) ,!3%6&amp;'() 3'#) +$&lt;&lt;.!,&amp;'() (!""') ,!3'+&lt;.!,3,&amp;.')
-30&amp;,+&gt;b) &amp;') N!.%""#&amp;'(+) .2) ,-") J\,-) &amp;',"!'3,&amp;.'31)
%.'2"!"'%") .') E$/3') 23%,.!+) &amp;') %./&lt;$,&amp;'() +*+,"/+&gt;)
U"4) j.!6&gt;) Uj&gt;) cOG&gt;) QE8) dVZ&gt;) &lt;&lt;7IVe^5IV]J&gt;) GQF&gt;)</p>
      <p>JVVZ7)
@AB) H3'&amp;"1) T"!#&amp;%-"9+6*) 3'#) M!&amp;6) U"$"'+%-43'#"!7) IZZZ7)
=.43!#) 3') ",-&amp;%+) .2) &lt;"!+$3+&amp;9") ,"%-'.1.(*7) Q.//$'7)</p>
      <p>GQF)eJ&gt;)])RF3*S&gt;)]I5]A&gt;)IZZZ7))
@ZB) F3!+-&amp;'&amp;) Q-",,*&gt;) H39&amp;#) =!3'&gt;) 3'#) P"0"%%3) M7) _!&amp;',"!&gt;)
a_",,&amp;'() ,.) (!""'X) $'#"!+,3'#&amp;'() !"+.$!%") %.'+$/&lt;,&amp;.')
&amp;') ,-") -./"&gt;b) &amp;') N!.%""#&amp;'(+) .2) ,-") IV,-) &amp;',"!'3,&amp;.'31)
%.'2"!"'%") .') c0&amp;K$&amp;,.$+) %./&lt;$,&amp;'(&gt;) U"4) j.!6&gt;) Uj&gt;)
cOG&gt;))c0&amp;Q./&lt;)dVA&gt;)&lt;&lt;7)JeJ5J]I&gt;)GQF&gt;)JVVA7)
@IVB) ?dH.''"11&gt;) i7G7) 3'#) H7`7) L3!#1.4&gt;) G) ,-".!*) .2) ,-")
.!&amp;(&amp;'+) .2) %..1'"++&gt;) G#93'%"+) &amp;') Q.'+$/"!) P"+"3!%-&gt;)</p>
      <p>J\&gt;))&lt;3("+7)I^)5)IA&gt;)JVVV7)
@IIB) N!.%-3+63&gt;) [7?7&gt;) U.!%!.++&gt;) [7Q7) 3'#) H&amp;%1"/"',"&gt;) Q7Q7)</p>
      <p>Q-3'(&amp;'()k.!)_..#7)G9.')T..6+&gt;)U"4)j.!6&gt;)IZZe7)
@IJB) =3&lt;&lt;&gt;) G7) 3'#) O7) T&amp;!#&gt;) O.%&amp;31) /3!6",&amp;'() 3'#) ,-")
/"3'&amp;'() .2) %..1&gt;) O.%&amp;31) F3!6",&amp;'() l$3!,"!1*&gt;) Ie&gt;) I)
&lt;3("+7)IA)5)JZ&gt;)JVVA7)
@I^B)=-")O1""&lt;)Q.$'%&amp;1)RJVV\S)[$'6)O1""&lt;X),-")U"4)E"31,-)
=-!"3,) ,.) =""'3("!+7) P",!&amp;"9"#) 2!./)
-,,&lt;XYY4447+1""&lt;%.$'%&amp;17%./Y[.$!'31&amp;+,+Y&lt;!"++m&lt;3%6+Y[$
'6mO1""&lt;m,-"m+$!9"*m+,.!*7#.%) R3%%"++"#) [3'$3!*)
JVIIS7)
Nudging People at Work and Other Third-Party Locations</p>
      <p>Max L. Wilson1, Derek Foster2, Shaun Lawson2, Simon Eddison1
1Future Interaction Technology Lab</p>
      <p>College of Science</p>
      <p>Swansea University, UK
m.l.wilson@swansea.ac.uk, simon.d.eddison@gmail.com
Lincoln Social Computing Research Centre</p>
      <p>School of Computer Science</p>
      <p>University of Lincoln, UK
{defoster,slawson}@lincoln.ac.uk
ABSTRACT
Nudging people towards positive behaviour change is an
important issue recognised by academia, individuals, and
even governments. Although much research has been
published in this area, little has focused on non-domestic
environments such as the workplace. It is widely reported
that changing individual behaviour of employees can make
a significant contribution to sustainable resource
consumption. This position paper focuses on the unique
aspects that make nudging consumption behaviour in
thirdparty environments like the workplace a very different
problem to that of nudging in people’s domestic and private
lives. Several studies are discussed to provide context as
well as evidence towards our position.</p>
      <p>Author Keywords
Persuasion, Nudge,
Behaviour Change.</p>
      <p>Work, Ownership, Sustainability,
ACM Classification Keywords
H5.m. Information interfaces and presentation (e.g., HCI):
Miscellaneous.</p>
      <p>General Terms
Theory, Human Factors, Design.</p>
      <p>INTRODUCTION
The HCI community has recently shown a great deal of
interest in the development of interactive systems that
facilitate behaviour change for sustainability. Much of this
research has exploited ideas recently re-popularised by
Thaler and Sunstein [10] in that individuals can be ‘nudged’
to make better lifestyle decisions, given the right
information and the environment in which to do so. Much
of this work has focused on how individuals might improve
their own private and domestic lifestyle, behaviour, and
sustainable resource consumption; however such work has
rarely taken account of the fact that people spend a
significant amount of their waking hours at work where
they also contribute towards resource consumption.</p>
      <p>Copyright © 2011 for the individual papers by the papers' authors.</p>
      <p>Copying permitted only for private and academic purposes. This volume is
published and copyrighted by the editors of PINC2011.</p>
      <p>A recent report [1] has indicated that if the 17 million UK
workers, who regularly use a desktop PC, powered it off at
night this would reduce CO2 emissions by 1.3 million tons
- the equivalent of removing 245,000 cars from the road.</p>
      <p>Similarly, if a UK business with 10,000 computers leaves
them on all night for one year, it will cost £168,000
($220,000) and emit 828 tonnes of CO2. The same report,
however, suggested that at least three in ten workers in the
UK do not always power off their PC overnight. Further,
many more machines are in use or provide services 24
hours a day, all year round.</p>
      <p>As an example in our own context, Figure 1 compares the
electricity usage at the University of Lincoln campus for the
first week in December in 2009 and 2010. There are two
compelling features of Figure 1 that characterise the typical
energy consumption of a workplace. First, the graph clearly
shows how little energy the university uses at the weekend.</p>
      <p>Second, this period in 2010 coincided with severe weather
that meant that many staff members were unable to travel to
the campus. The dramatic reduction in energy consumption
can be clearly seen in the first 3 days of the graph and
highlights that people can have a significant impact on
consumption at work, as well as in their own personal
environments.</p>
      <p>Figure 1 Campus electricity usage December 2009/10
Despite environmental concerns now playing an established
role in the public sector, as well as the corporate and
business agenda, there is still much to gain by exploring
new ways of persuading people to adopt positive energy
usage behaviour. The first and obvious research question is:
Do domestic PINC (Persuasion, Influence, Nudge &amp;
Coercion) methods simply translate to workplace and other
third-party environments? In this position statement we
review initial evidence that they do not, and discuss the
reasons why. We propose a framework for thinking about
Nudge methods in different contexts, and discuss our future
work in this area.</p>
      <p>RELATED WORK
Thaler and Sunstein [10] have recently re-popularised the
interest in the idea of Nudge, where the right environments
and the right information delivered at the right time can
encourage people to adapt and improve their behaviours.</p>
      <p>Much research has focused on directly improving one’s
own behaviour, whether it be reminders to exercise, or to
notably reduce energy consumption. Research into simple
home energy monitors [3], for example, suggests that
payas-you-go meters typically reduce consumption by only 3%,
while those that focus on reducing their payments often
reduce their consumption by 0-10%. Having an in-house
monitor that provides instant feedback has been shown to
reduce consumption by between 5 and 15%. Other
prototype systems, such as Kuznetsov and Paulos’s
domestic ambient light display [7] successfully encouraged
people to reduce their water consumption, by visualising
better or worse consumption to their previous average use.</p>
      <p>Other research typically provides anonymous averages from
a group or community to a user, so that the user can see
their own behaviour or consumption in the context of
others. In previous work [5], we reduced domestic energy
consumption through a carefully designed mixture of online
social media and home energy monitors. Our findings
suggested that the use of energy feedback delivered in a
social context significantly reduced consumption when
compared to energy feedback without a social context. We
have also shown similar results in a personal fitness/activity
domain [4].</p>
      <p>A related approach involves facilitating ‘friendly’
competitive behaviour; for instance it has already been
shown that the work environment affords powerful
opportunities for facilitating such behaviour – for instance
Siero et al [8] demonstrated that when a group of
employees received information not only about their own
energy usage, but also about that of a ‘competing’ group of
employees from the same company but a different
workplace, they significantly altered their energy usage
behaviour compared to a situation in which they only
received information about their own usage.</p>
      <p>Despite the success of the work by Siero et al some thirteen
years ago, little research since has explored energy
behaviour interventions based on competition between
employees. Therefore, a key question for Nudge researchers
going forward is how do differences between the work and
domestic leisurely sides of life affect the potential of
behaviour change interventions? Also, what theoretical
grounding can we draw upon to begin to explore any
differences? Stebbins [9] introduced a seminal framework
for understanding people’s leisure time. For some, being
environmentally friendly is, as Stebbins called it, a Serious
Leisure, where people work hard at achieving their goals.</p>
      <p>Installing home technology is often a temporary project,
and can be seen as Project Leisure, where people take
behaviour change to be a new task. The aim of much
nudging research, however, is to be embedded in people’s
Casual Leisure, so that good consumption is encouraged
simply and unobtrusively within our lives. These forms of
leisure, however, are very different from our work lives,
which are goal-oriented, formalised, and externally driven.</p>
      <p>EARLY EXPERIMENTAL FINDINGS
Study 1 – Water Consumption in the Work Place
One early finding in this space was from Kuznetsov and
Paulos [7] who anecdotally saw unexpected results in a
work environment, and so proceeded to focus on domestic
scenarios. Their anecdotal findings saw consumption
increase – double in fact.</p>
      <p>One of our recent studies in Swansea University, UK,
focused directly on this surprising issue. We created a series
of feedback installations, and installed them in a shared
work-place kitchen. Like the work by Kuznetsov and
Paulos, the installations used a Phidget microphone to track
water flow through the pipes. The installations were
supported by informational posters, which included a link
to a website to provide feedback. Otherwise, we remained
as un-intrusive as possible in order to record normal usage
as closely as possible. After recording baseline average
readings, we first recreated the ambient light display
provided used by Kuznetsov and Paulos, which: glowed
green with less-than-average consumption; glowed yellow
10% either side of the mean; and glowed red thereafter.
Three further displays were installed in subsequent weeks.</p>
      <p>The first used similar measures, in respect to average
consumption, to create competitive gaming-style
textoriented messages on an LED display, such as: “You’re
beating most people” and “Sorry, you lost”. The second
display converted the light system into a series of audible
beeps. The final display tried a different tack altogether, by
simply providing environmental information relating to
their water consumption, such as the average amount of
water available to people in the third world on a daily basis.</p>
      <p>Initially, as per the prior anecdotal evidence, the ambient
light display did double the average consumption of water
during the 2 weeks it was displayed. In comparing studying
the additional displays, we saw all but the audio condition
increase the consumption. While the increase shown by
these alternatives was significantly less than the ambient
light display in particular, none were significant. Although
the audio feedback did marginally reduce consumption, we
also recorded a significant number of opt-out button presses
in the audio condition, indicating that people disliked this
particular installation. Qualitative comments from an
optional online survey confirmed this. Given the surprising
increase created by the ambient light display, we concluded
the study by reinstalling the ambient light display for a final
week. Although not quite double the average consumption,
we again saw a significant increase in energy consumption.</p>
      <p>In the end, none of the displays managed to significantly
decrease consumption of water. It is promising, however,
that not all the displays increased consumption
significantly. This means that such displays do not simply
have the opposite effect in work environments. Instead, the
results suggest that people simply do not care for the
consumption of the company as a whole, and potentially do
not mind entertaining themselves with the resources of the
company by using additional resources. The fact that
significantly more users opted out of the audio display,
which was the only one to reduce average consumption,
further indicates that people do not mind avoiding resources
in this area; that they do not feel personally motivated to
accept the nudging technology.</p>
      <p>Study 2 – Energy Consumption in the Work Place
Our recently commenced Electro-Magnates study [6] aims
to reduce energy usage in the workplace by utilising a suite
of social persuasive applications to encourage
proenvironmental behaviours. Personal desktop applications
(social widgets) and situated displays will be used to deliver
energy feedback to individuals, groups and communities
about their own – and others’ – energy usage to foster
exchange of performance and to support constructive
competition to reduce consumption. The workplace in the
context of this study is educational and public sector
workplace environments in the county of Lincolnshire, UK.</p>
    </sec>
    <sec id="sec-36">
      <title>In previous work [5], we reduced domestic energy</title>
      <p>consumption through social norms and social technology.
However, designing a similar system for the workplace
presents greater challenges across a range of design, ethical
and technical issues. From our study focus groups in the
domestic environment we discovered that for some people
cost was the primary motivating reason to reduce their
energy use. In the workplace employees are not typically
responsible for paying energy costs, neither are they
directly responsible for meeting any governmental carbon
policies in place that could lead to institutional ‘carbon’
fines.</p>
      <p>To mitigate the absence of financial motivation in
employees and to develop workplace energy metaphors, we
intend to run a series of focus groups and participatory
design workshops to engage and empower the employee in
developing an understanding of both the economic and
environmental impact of their working practices. The
participatory design workshops will provide an opportunity
for employees to be directly involved in designing the UX
element of Electro-Magnates therefore helping to address
ethical concerns over privacy and appropriate disclosure of
energy data.</p>
      <p>Early work to date includes prototyping a high-impact
energy interface for overall energy usage in Figure 3, page
viewed on 09/01/2011, as well as a competitive league table
for buildings. Both prototypes are designed for large
situated displays and are abstracted presentations of what is
possible with raw energy sensor data which in itself is
intangible and difficult to interpret.</p>
      <p>Figure 3 High-impact visualisation of overall energy usage
DISCUSSION
The workplace, as an example of a non-domestic,
nonpersonal environment, creates many unique issues for the
ideas behind nudging behaviour. Consequently, we have
identified three initial dimensions that differentiate
domestic and workplace environments that might be used as
a formative framework for thinking about applying nudging
technology in different
environments:Expression of Self. First, the workplace may be termed a
special environment in that there are usually constraints and
rules in how employees can interact and carry out activities
in the workplace compared to their less inhibited personal
life. This is particularly important when considering
employee consumption of resources with emphasis on
ownership, freedom of choice and sustainable behaviour.</p>
    </sec>
    <sec id="sec-37">
      <title>Ironically, an individual may be committed to proenvironmental behaviour when at home but is forced to</title>
      <p>Sense of Responsibility. Second, prior research typically
assumes that individuals are trying to change their
behaviour, or reduce their consumption, but for many the
workplace is not their own and not their responsibility.
Consequently, not only is the environment and technology
controlled for them, people have a diminished sense of
responsibility for the energy costs and environmental
impact.</p>
      <p>External Constraints. Third, the workplace or type of work
has its own requirements – they may need to maintain
24-7365 server support. It may be normal for some businesses to
have 3 or more machines running per individual, but
unusual for others to have a computer at all. This kind of
top-down requirement might make individuals feel out of
control of the environment and its consumption, leading to
lack of motivation.</p>
      <p>
        Given these limiting and influential factors, it is hard to
consider how we can utilise the same nudging technology
that we typically apply in domestic contexts. The few
successful workplace nudging installations have typically
been dependent on a driven community. The CleanSink
project [
        <xref ref-type="bibr" rid="ref2">2</xref>
        ] saw some positive influence in hospitals, where
cleanliness is both required and important for care. Our
ongoing study on energy consumption in Lincoln, is focusing
on driving community motivation, which may encourage
expression of self and increase sense of ownership, whilst
working within the external constraints of the workplace.
CONCLUSIONS AND FUTURE WORK
Much of the prior research on Nudge, and other PINC
issues, has assumed that individuals are focusing on their
environments, behaviours, consumption, and other things
that they are in some control over. How does Nudge fare in
environments, like the workplace, that are typically outside
of an individual’s control? Such questions are important for
larger organisations who want to improve their collective
behaviour, whether it is a business trying to reduce its own
consumption or meet it’s quota of carbon credits, or a
government trying to reduce the nation’s consumption.
In our future work, we are focusing on this issue in two
ways. First, our funded research is focusing further on
encouraging community-driven nudges for reducing
business and employee consumption. Second, we are
planning future studies that specifically investigate the
nudge of groups and communities rather than of
individuals, as to meet the UN’s Millennium Goals1, we
need to nudge the behaviour of the global community and
not just that of individuals.
      </p>
      <p>REFERENCES
[1] 1E PC Energy Report 2009. online at
http://www.1e.com/Energycampaign/Index.aspx
[7] Kuznetsov, S. and Paulos, E. UpStream: Motivating
Water Conservation with Low-Cost Water Flow Sensing
and Persuasive Displays. In Proc. CHI 2010, ACM Press
(2010).
[8] Siero, F.W., A.B. Bakker, G.B. Dekker, and M.T.C. van
den Burg. . Changing organizational energy consumption
behavior through comparative feedback. In Journal of
Environmental Psychology 16: 235-246. (1996)
[10] Thaler, R and Sunstein, C. (2008) Nudge: Improving
Decisions About Health, Wealth, and Happiness: Yale
University Press.</p>
    </sec>
  </body>
  <back>
    <ref-list>
      <ref id="ref1">
        <mixed-citation>
          <article-title>We'd like to thank the NIMD2010 participants for discussions. The Electro-Magnates project is funded by the HEFCE LGM fund</article-title>
          .
        </mixed-citation>
      </ref>
      <ref id="ref2">
        <mixed-citation>
          [2]
          <string-name>
            <surname>Arroyo</surname>
            ,
            <given-names>E.</given-names>
          </string-name>
          ,
          <string-name>
            <surname>Bonanni</surname>
            ,
            <given-names>L.</given-names>
          </string-name>
          and
          <string-name>
            <surname>Selker</surname>
            <given-names>T.</given-names>
          </string-name>
          ,
          <article-title>Waterbot: Exploring Feedback and Persuasive Techniques at the sink</article-title>
          ,
          <source>In Proc CHI</source>
          <year>2005</year>
          , ACM Press(
          <year>2005</year>
          ) [4]
          <string-name>
            <surname>Foster</surname>
            ,
            <given-names>D.</given-names>
          </string-name>
          ,
          <string-name>
            <surname>Linehan</surname>
            ,
            <given-names>C.</given-names>
          </string-name>
          ,
          <string-name>
            <surname>Lawson</surname>
            ,
            <given-names>S.</given-names>
          </string-name>
          , and
          <string-name>
            <surname>Kirman</surname>
            ,
            <given-names>B.</given-names>
          </string-name>
          <article-title>Motivating physical activity at work: using persuasive social media for competitive step counting</article-title>
          .
          <source>In Proc. Mindtrek</source>
          <year>2010</year>
          , ACM Press(
          <year>2010</year>
          ) [6]
          <string-name>
            <surname>HEFCE</surname>
          </string-name>
          <year>2010</year>
          . online at http://www.hefce.ac.uk/lgm/build/lgmfund/projects/show.as p?
          <source>id=195&amp;cat=15</source>
        </mixed-citation>
      </ref>
    </ref-list>
  </back>
</article>