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  <front>
    <journal-meta>
      <journal-title-group>
        <journal-title>June</journal-title>
      </journal-title-group>
    </journal-meta>
    <article-meta>
      <title-group>
        <article-title>Designing Micro-intelligences for Situated Afective Computing</article-title>
      </title-group>
      <contrib-group>
        <contrib contrib-type="author">
          <string-name>Peter Lovei</string-name>
          <xref ref-type="aff" rid="aff2">2</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Suhaib Aslam</string-name>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Iryna Nazarchuk</string-name>
          <xref ref-type="aff" rid="aff1">1</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Natalia Sidorova</string-name>
          <xref ref-type="aff" rid="aff1">1</xref>
        </contrib>
        <aff id="aff0">
          <label>0</label>
          <institution>Bin Yu</institution>
          ,
          <addr-line>Carl Megens, Philips Experience Design, Eindhoven</addr-line>
          ,
          <country country="NL">The Netherlands</country>
        </aff>
        <aff id="aff1">
          <label>1</label>
          <institution>Department of Computer Science, Eindhoven University of Technology</institution>
          ,
          <addr-line>Eindhoven</addr-line>
          ,
          <country country="NL">The Netherlands</country>
        </aff>
        <aff id="aff2">
          <label>2</label>
          <institution>Philips Experience Design, Department of Industrial Design, Eindhoven University of Technology</institution>
          ,
          <addr-line>Eindhoven</addr-line>
          ,
          <country country="NL">The Netherlands</country>
        </aff>
      </contrib-group>
      <pub-date>
        <year>2021</year>
      </pub-date>
      <volume>8</volume>
      <issue>2021</issue>
      <abstract>
        <p>In this position paper we show how micro-intelligences can be used to remotely collect behavioral, contextual and experiential data. We introduce two micro-intelligences that are built for being the physiological and afect annotation layers of a broader intelligent ecosystem. We describe how we used this system to conduct rapid, autoethnographic experiments to understand how working from home impacts emotional states and physiology of ofice employees. We discuss how our micro-intelligences build on top of one another and how they can be enriched using a qualitative reflection layer. We aim to inspire novel directions for creating situated, adaptive design interventions that can enable afective computing using IoT components.</p>
      </abstract>
    </article-meta>
  </front>
  <body>
    <sec id="sec-1">
      <title>CCS CONCEPTS</title>
    </sec>
    <sec id="sec-2">
      <title>INTRODUCTION</title>
      <p>
        When designing for afective computing [
        <xref ref-type="bibr" rid="ref12">12</xref>
        ] it is possible to apply
the Data-Enabled Design [
        <xref ref-type="bibr" rid="ref7">7</xref>
        ] process. Data-Enabled Design (DED)
has proved to be valuable for collecting behavioral, contextual and
experimental data [
        <xref ref-type="bibr" rid="ref3 ref6">3, 6</xref>
        ]. As DED is a situated design approach it
allows design (researchers) to explore a remote context from the
design studio. The DED process is a multi-step approach involving
a research-oriented contextual, and a design-led informed step. The
method is suitable for times when it is not possible for design
(researchers) to meet their study participants in person. However, we
needed to realize that it is not true for all the stages. The
researchoriented contextual step serves to inspire and inform the design
Copyright 2021 for this paper by its authors. Use permitted under Creative Commons
License Attribution 4.0 International (CC BY 4.0).
process. There is value in collecting more qualitative data via
contextual inquiries or interviews during this step. These activities
require a higher level of in-person contact. Moreover, many of the
“design plumbing” [
        <xref ref-type="bibr" rid="ref8">8</xref>
        ] activities before remote data collection could
begin require the collected contextual insights.
      </p>
      <p>We were in the process of setting up the contextual step of a study
at a hospital when the Coronavirus pandemic began. The
circumstances made it impossible to follow our initial intentions to
iteratively develop, test and improve our intelligent ecosystem together
with healthcare professionals as study participants. We realized that
our initial setup for the research-oriented contextual step too much
relied on the possibility to be present in real-life at the hospital
context. Therefore, we decided to take a step back, and focused on
the improvement of the experience-related and the
functionalityrelated aspects of our upcoming contextual step by running small
experiments in the working from home context of our study team.
In this position paper we show how our team built a physiological
and an afect annotation layer for post-hoc reflections, collecting
physiological signals and enabling event annotations. We introduce
the concept of micro-intelligences for situated afective computing.
We discuss our study setups, and the results of our experiments.
Finally, we conclude on our plans to combine the separate layers
in one intelligent ecosystem that can be used for conducting our
contextual DED step.
2</p>
    </sec>
    <sec id="sec-3">
      <title>DESIGN DECISIONS</title>
      <p>We started our project with the intention to be able to remotely
collect behavioral, contextual and experimental data from healthcare
professionals (HCP) during their work hours from their hospital
context. The topic of our research is to find out what are moments
of interest related to the HCP’s work-life experience. During the
ifrst, preparation phase of our project we were still able to carry
out interviews, co-creation sessions, and a shadowing study with
our clinical partners. Based on these activities we have made the
following design decisions for our planned contextual DED step at
the hospital.
2.1</p>
    </sec>
    <sec id="sec-4">
      <title>Post-hoc reflections</title>
      <p>Firstly we looked for a method to gather post-hoc reflections about
the participating healthcare professional’s workdays. We needed to
be careful as we did not want to increase their workload. Therefore,
we need to limit the number of interactions with our ecosystem
during their workday. We decided to focus on enabling them to
reflect on their workday when they are finished with all their tasks.
In practice, this would require about 5 minutes of their time to
answer questions that are asked via a Chatbot that runs on one
of the major messaging platforms. By having reflection questions
asked on their phone we expect the professionals to be able to
recall the interesting moments that happened during their workday.
Moreover, many of them have access to their work calendar on
their phone and therefore can consult this data stream to remember
what they were doing at the specific timeframes they’re interested
to share with us about their workday.
2.2</p>
    </sec>
    <sec id="sec-5">
      <title>Physiological signals</title>
      <p>
        In combination with the post-hoc reflections our team is also
interested whether there are physiological signals that can be measured
at the moments that are of interest for the healthcare professionals.
Therefore, we looked for a way to collect objective behavioral data
from the context. We decided to collect Heart rate variability (HRV)
data. HRV represents non-invasive, unobtrusive information about
modulation of heart rate by the autonomic nervous system in a
variety of dynamic circumstances, including evoked emotions, and
exercise [
        <xref ref-type="bibr" rid="ref4">4</xref>
        ]. It is commonly defined as the fluctuation in the time
intervals between adjacent heartbeats that are called R-waves [
        <xref ref-type="bibr" rid="ref13">13</xref>
        ].
Health and self-regulatory capability, and adaptability or resilience,
are correlated with an optimal level of HRV. In general, variability
represents the capacity of the body to deal with stressors. Any big
change away from the baseline may be an indication that
overtraining, sickness or just lack of sleep. In recent years, the number of
studies related to HRV has risen steeply. For example, researches
have indicated that acute stress has been associated with decreased
HRV during sleep and during the daytime [
        <xref ref-type="bibr" rid="ref9">9</xref>
        ]. In addition, decreased
HRV has been associated with work stress in multiple studies [
        <xref ref-type="bibr" rid="ref16 ref5">5, 16</xref>
        ].
Therefore, we consider the HRV to be a relevant data source for
deriving physiological insights. Based on our interviews the
healthcare professionals indicated that they preferred to wear the HRV
tracker on their arm over their wrists or chests.
2.3
      </p>
    </sec>
    <sec id="sec-6">
      <title>Event annotations</title>
      <p>
        Based on our pre-contextual study steps we noted that sharing
the overall explanation of one’s workday with our design team
can wait until the participant is finished with their workday. We
described in our post-hoc reflection section that it is possible to
recall an overall impression about the day and potentially use other
data sources one has access to. However, there are moments that
are important to be noted at the moment they happen. Our team
decided to look into the possibility to make it easily possible in the
contextual step to mark the exact time of such events happening in
a participant’s workday by a physical design probe (e.g. an event
annotation button). Marking these events have two main advantages:
(1) it can function as an additional data stream for the participant
when answering the post-hoc reflection questions, (2) the design
(researchers) can use the annotated events in combination with
the physological signals. Both of these techniques result in a better
understanding of the workday.
Inspired by the micro-services architecture [
        <xref ref-type="bibr" rid="ref10">10</xref>
        ] we aimed to
translate our design decisions into micro-intelligences. By the term
microintelligence we mean an intelligent, self-contained layer that embeds
all the experience-related and functionality-related components
that one needs to combine in order to collect, analyze and visualize
behavioral, contextual and experimental data. The aim of designing
micro-intelligences instead of the overall intelligent ecosystem are
(1) for design (research) teams to be able to reuse the built
microintelligences across multiple DED studies, (2) being able to evaluate
both experience-related and functionality-related aspects of
intelligent ecosystem components, finally, (3) micro-intelligences to have
a difering degree of automation when included in the intelligent
ecosystem. We designed two micro-intelligences: (1) the
physiological layer and (2) the afect annotation layer of our upcoming DED
study, and we ran four asynchronous experiments with members
of our research team while they were working from home.
3.1
      </p>
    </sec>
    <sec id="sec-7">
      <title>Physiological layer</title>
      <p>
        The physiological layer is a micro-intelligence that was built
applying our design decisions to (1) enable post-hoc reflections on
one’s workday, and (2) to facilitate the collection of HRV data
remotely. This layer consists of the following components: (1) a
Scosche Rhythm24 Heart Rate Monitor, (2) a messaging platform,
(3) a Bluetooth Low Energy (BLE) enabled device (e.g. a computer,
or a smart phone), (4) software tools enabling HRV analysis
(Kubios [
        <xref ref-type="bibr" rid="ref15">15</xref>
        ], Elite HRV [
        <xref ref-type="bibr" rid="ref11">11</xref>
        ]). We tested the experience-related and
the functionality-related capabilities of this micro-intelligence by
collecting data from two members of our research team from their
working from home context.
3.1.1 Collecting physiological signals. For this experiment we
selected a wearable heart rate monitor that can be worn on the arm of
our first participant. The Scosche Rhythm24 Heart Rate Monitor is
a Bluetooth Low Energy optical HR band, that is able to collect the
heart rate and inter-beat interval data using Valencell PPG-based
sensor that was previously validated with respect to ECG to
provide accurate measurements [
        <xref ref-type="bibr" rid="ref17">17</xref>
        ]. We evaluated this experiment
setup for one person in order to assess its potential feasibility. Using
this wearable data was collected during a predefined set of tasks
within 6 separate intervals, each lasting 25 minutes and consisting
of 5 repeated episodes, that were all including physical activity
with diferent levels of intensity. With this experiment we aimed at
recording noisy data that potentially contains a lot of missing values
due to the motion artifacts and signal loss issues. Specifically, the
data collection was performed for the following recorded physical
states: resting phase with deep breathing, training, cooking,
cleaning, washing the dishes and watering the plants. IBI time series data
was extracted using a custom Node.js script that was running on
the participant’s laptop and enabled the real-time data acquisition
from the sensor using the Bluetooth Low Energy connection. The
data was sent in packages, containing several characteristics (e.g.
timestamp, Heart Rate Measurement value, Energy Expended, R-R
intervals, etc) varying in size from 20 bytes to 236 bytes with a
maximum data transfer rate from 222 bytes/sec to 2186 bytes/sec [
        <xref ref-type="bibr" rid="ref1">1</xref>
        ]. At
the end of every recording session, the Node.js script was storing
the acquired structured data in a file with a CSV format.
      </p>
      <p>
        The results of the data collection are in Table 1. The data suggests
that the highest percentage of missing data occurs while performing
the cleaning activity (58%). That can be explained by the
significant amount of movement during the data collection process and
connectivity to the receiving device that afects the quality of the
signal and subsequently leads to data loss. It can be expected that
devices using the same technology will have the same problem.
In the meantime, the lowest percentage of losing data appears for
resting phase data collection (8%) while the participant is located
close to the signal receiving device and is not involved in any
dynamic activities. This high data loss highlights the limitation of
relying solely on the HRV data. The HRV only indicates arousal,
but not valence. Thus, to meaningfully understand the experience
and clearly distinguish the context between the same HRV results,
the physiological states derived from the HRV need to be linked to
the ground truth to express valence. This can be achieved by
involving additional input sources that provide the ability for collecting
post-hoc reflection, and event annotation data. At the same time,
our micro-intelligence setup has the advantage of being able to
continue this experiment with the aim of determining the possible
improvements (e.g. the location of the data receiving device) that
would facilitate the quality of calculated HRV parameters while
continuing our preparation for the contextual DED step [
        <xref ref-type="bibr" rid="ref14 ref18 ref2">2, 14, 18</xref>
        ].
3.1.2 Combining physiological signals and post-hoc reflections. As
we learnt from the first experiment we needed to introduce
additional data sources applying our design decision to enable post-hoc
reflections of participants. Our hypothesis was that our contextual
insights can be improved by the introduction of the possibility to
ask participants about their physiological signals. For this
experiment we asked our second participant to use the same Scosche
heart rate monitor, and the Elite HRV mobile application for data
collection [
        <xref ref-type="bibr" rid="ref11">11</xref>
        ]. For analysis purposes we used Kubios [
        <xref ref-type="bibr" rid="ref15">15</xref>
        ]. At the
end of each working day the design (researcher) generated a
visualization about the (interesting moments) of the participant’s
workday combined with questions about them and shared these
via WhatsApp. The participant was able to reply and send post-hoc
reflection data to the researcher (See figure 2). We ran this study
for 10 days, while the participant was working from home. We
asked the participant to collect as much HRV data as possible with
the application, and to answer the post-hoc reflection questions
directly after their workday. At the end of the experiment we ran a
data-enabled interview with the participant and reflected on our
main findings.
      </p>
      <p>Based on the collected data and the insights we gathered via the
interview it was clear that our hypothesis that the participant could
reflect on their day looking at their daily visualization was
conifrmed. The participant reported that the sensor’s measurements
were a good indicator of the moments when their heart rate
variability was diferent compared to their baseline. When the participant
was looking at their visuals it was possible to let our team know
about what happened at those moments. Many times the
participant could not fully recall what happened in their workday during
the highlighted time but in this case they looked at their agenda.
We also noted a significant experience-related finding, namely that
measuring heart rate variability made the participant pay more
attention to the stressful or rather negative moments of their day
when sending us their post-hoc reflections. This finding has enabled
our team to better scope the afect annotation layer of our DED
study.
3.2</p>
    </sec>
    <sec id="sec-8">
      <title>Afect annotation layer</title>
      <p>The afect annotation layer is a micro-intelligence that was built
applying our design decisions to (1) enable post-hoc reflections on
one’s workday, and (2) to facilitate event annotations. This layer
consists of the following components: (1) two Flic buttons, (2) a
messaging platform that can be programmed by Flow.ai, (3) a
smartphone, and (4) software tools enabling event annotation analysis
(e.g. AWS Lambda function, local Python script). We tested the
experience-related and the functionality-related capabilities of this
micro-intelligence by collecting data from three members of our
research team from their working from home context.
3.2.1 Collecting post-hoc reflections. Our way of working of
developing our DED contextual step as micro-intelligences enabled
our team to run a study that focused on our hypothesis related
to the experience-related aspect of our design decision to enable
post-hoc reflection’s on one’s workday. For this experiment we
intended to figure out whether a chatbot would be adequate to use
as a daily reflection journal. We setup a WhatsApp group with our
third participant and asked them to use it as their personal diary to
collect their reflections on working from home as a designer. Our
design researcher sent a list of generic working from home related
topics at the end of every workday. The participant could choose
what to reflect on from that list. This provided them a trigger for
sending us their post-hoc reflections. The participant was also
allowed to reflect on something that was not present on the list. We
ran this experiment for seven days. Our main finding was that this
way of post-hoc reflection quickly became monotonous and too
repetitive and this resulted in less and less nuanced responses from
our participant. Therefore, we decided to focus our team’s attention
to develop the afect annotation layer further to overcome these
shortcomings.
3.2.2 Combining post-hoc reflections with event annotations. Our
ifnding about the need to enable participants to be able to report
positive events happening during their workday that is described in
3.1.1 highlighted the need to provide an event annotation option for
them. Moreover, we wanted to make sure that the way we collect
post-hoc reflections at the end of the workday does not become
monotonous and repetitive. Flic buttons are Bluetooth Low Energy
enabled IoT devices that can be used for this purpose. The buttons
are connected to their companion app running on a smartphone.
When one presses the buttons it sends this to the Flic app. Inside
the Flic application it is possible to program what action such
physical press would trigger. We gave two Flic buttons each to our
second and fourth participant. We instructed them to press these
buttons during their workday when they recognized that either
positive or negative moments were happening. Inside the Flic app
we setup a POST request that would send JSON data containing
the timestamp and whether the positive or the negative button
was pressed to our backend. We programmed the Flow.ai Chatbot
platform to trigger a WhatsApp message at 17.00 after the end of
the participants’ workday. The participants were asked to rate their
workday. In response to their reply they were presented with a list
of their positive and negative moments. Finally, they were asked
to elaborate on their day (See figure 3). We ran this experiment
for 7 days with two participants working from home. After the
experiment we conducted data-enabled design interviews where
the participants were presented with their collected data, and they
could reflect on it.</p>
      <p>Based on the collected data and the follow-up interviews of this
experiment we learnt that the insights we could collect from our
participants about their workday difered a lot from the insights
we gathered using the physiological layer or during the experiment
for collecting post-hoc reflections. We could notice from the replies
that the participants were focusing to tell more about the positive
aspects of their workday. They reported this was also due to the
clear conscious action required to press a physical button. During
their end of the day reflection it was mostly possible to recall why
they pressed the buttons. Based on this experiment we verified
that we are able to execute our design decision to introduce event
annotations as a reflection tool on one’s workday.
4</p>
    </sec>
    <sec id="sec-9">
      <title>CONCLUSIONS</title>
      <p>In this position paper we introduced what micro-intelligences are.
Based on the evaluation of four experiments carried out in the
working from home context of our design research team we reflected
on their characteristics when designing and developing them as
preparation for a contextual DED step.</p>
      <p>Firstly, as each micro-intelligence is a self-contained layer of a
broader intelligent ecosystem it is possible to reuse them across
several DED studies. We showed that this is the case as the four
experiments introduced across the two micro-intelligences
introduced in this paper all use common components and infrastructure
and are developed in a way that it would be possible to reuse them
by other design (research) teams.</p>
      <p>Secondly, we showed that when using the designed micro-intelligences
it is possible to evaluate modular components of an intelligent
ecosystem. In our experiments we were able to adjust whether the
design (research) would focus on testing the experience-related or
the functionality-related aspect of a component. We evaluated our
design decision of collecting post-hoc reflections using a chatbot
in three diferent ways (see figure 4). First, we used the chatbot
component to learn about the experience-related aspects of
collecting post-hoc reflection data. Then we combined the chatbot with
heart rate variability data and could focus our attention on both
functionality related (can participants provide post-hoc reflections
based on their HRV data) and experience-related (what graphs to
include in the chatbot messages) aspects. We could also separately
test the functionality-related aspect of how to connect our chatbot
to the afect-annotation layer that enables event annotations.
Lastly designing micro-intelligences enables the testing of the level
of automation required to be developed for the modular
components of an intelligent ecosystem. In our four experiments presented
in this positioning paper we could flexibly decide whether to use
the components as fully-automated data trackers (a chatbot that can
automatically retrieve data from the event annotation component)
or in a Wizard of Oz prototyping style (the design researcher
manually generated and sent out the HRV graphs to the participant).
As stated earlier, our next step is to combine the separate
microintelligence layers in one intelligent ecosystem, that can be used to
collect, analyze and visualize behavioral, contextual, and
experimental data from healthcare professionals that work at a collaborating
hospital partner. Our research will focus on enabling the
healthcare professionals to annotate positive and negative moments of
their workday. We will also collect their physiological signals to see
whether their reported moments could be confirmed by objective
data. At the end of their workday we will collect post-hoc
reflections using a chatbot.</p>
      <p>With the work presented in this paper, we set out to employ a
micro-intelligence approach for designing and testing two layers
for situated afective computing (the physiological layer and the
afect annotation layer). The experiments discussed enabled us to
further refine our design decisions and to uncover experiential
or functional gaps in our micro-intelligences. With this, we have
tried to take a first step towards designing a broader intelligent
ecosystem for conducting afective computing in a situated manner.</p>
    </sec>
  </body>
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