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  <front>
    <journal-meta />
    <article-meta>
      <title-group>
        <article-title>The Art of Spending and Recommendations in Personal Finance</article-title>
      </title-group>
      <contrib-group>
        <contrib contrib-type="author">
          <string-name>Leonid Ivonin</string-name>
          <email>leonid.ivonin@bristol.ac.uk</email>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Mark Perry</string-name>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Sriram Subramanian</string-name>
          <xref ref-type="aff" rid="aff1">1</xref>
        </contrib>
        <aff id="aff0">
          <label>0</label>
          <institution>Department of Computer Science, Brunel University</institution>
          ,
          <addr-line>London</addr-line>
          ,
          <country country="UK">UK</country>
        </aff>
        <aff id="aff1">
          <label>1</label>
          <institution>Department of Computer Science, University of Sussex</institution>
          ,
          <addr-line>Brighton</addr-line>
          ,
          <country country="UK">UK</country>
        </aff>
      </contrib-group>
      <fpage>24</fpage>
      <lpage>28</lpage>
      <abstract>
        <p>Happiness is one of the most important aspects of human lives, yet the literature on emotional well-being indicates that people often fail to correctly anticipate the hedonic consequences of future events. As a result, individuals end up being not as happy as they thought they would be. This phenomenon also applies to the domain of personal finance where people make bad decisions about purchases. In this paper, we identified a new opportunity for the research on recommender systems in personal finance and through analysis demonstrated that intelligent recommenders can help to minimize errors in affective forecasts and enhance happiness of people in the domain of consumption. Furthermore, we reviewed problems associated with design of such recommenders and proposed approaches to overcome them.</p>
      </abstract>
    </article-meta>
  </front>
  <body>
    <sec id="sec-1">
      <title>1 INTRODUCTION</title>
      <p>One of the most fundamental instincts that people have is to be
happy and to live a good life. There are many criteria for defining a
good life but an important point is that an evaluation of one's life is
a subjective process. Positive psychology defines a happy life more
formally using the notion of "subjective well-being" (SWB). SWB
refers to how people evaluate their lives in terms of both affective
and cognitive aspects. There are several components of SWB such
as a general life satisfaction, satisfaction with important domains
(e.g., relationships with loving others), and positive affect
(experiencing pleasant moods and emotions) [1]. Improvements in
any component of SWB can help to increase a person’s happiness.
It seems that nowadays ordinary people tend to grant increasing
importance to SWB. This is especially true in developed countries
where basic material needs of people are satisfied and they are
progressing towards the post-materialistic phase of self-fulfillment
[2].</p>
      <p>Often people are looking for earning more money in the quest for
having a happy life. There is a common belief that more income has
a positive impact on well-being and can make people feel happier.
Therefore, a desire for higher income is a common motive among
many people at all income levels [3]. On the other hand, research on
income and SWB showed that among the non-poor the relationship
between money and happiness is surprisingly weak. Although
money seems to be able to buy happiness, it buys much less than
what most people think. Data showing a weak correlation between
SWB and income presents a puzzle [3]. Absence of a strong
relationship is intriguing because as Dunn, et al. [4] argued "money
allows people to live longer and healthier lives, to buffer themselves
against worry and harm, to have leisure time to spend with friends
and family, and to control the nature of their daily activities – all of
which are sources of happiness". Moreover, people with high
income have better nutrition, more free time, and more meaningful
labor. The contradiction between potential possibilities for
improving well-being offered by money and the lack of a strong link
between SWB and income seems to be partly explained by the fact
that people often are not particularly happy with their purchases.</p>
      <p>When individuals make a decision to buy something, they usually
try to make predictions about the hedonic value or consequences of
this purchase in the future. The process of foreseeing the future with
respect to affective states is called affective forecasting and,
according to the review provided by Wilson and Gilbert [5], people
are often wrong in their forecasts. They discovered several sources
of biases that cause errors in affective forecasting. Any of them
could lead to inaccurate predictions and the situation where a
wealthy person is not much happier than anyone else. Overall, it
seems that in most of the cases people are neither good in affective
forecasting nor are aware of characteristics indicating purchases that
will potentially make them happier, and for this reason, do not use
the opportunities for better SWB provided by wealth.</p>
      <p>We suggest that people can potentially benefit from a
recommender system with abilities to improve their affective
forecasts and to offer intelligent guidance about spending. Many
psychological biases that disturb affective forecasts of individuals
are known to behavioral scientists and documented in the literature.
For this reason, we argue that design of such a recommender system
should be feasible taking into account excellent progress in the area
of recommender systems that we saw from the early 1990s.</p>
      <p>To the best of our knowledge, current research in recommender
systems has not yet approached the problem of forecasting
enjoyment and satisfaction in the domain of personal finance. We
are still to see if technology can help people become happier with
their purchasing decisions and improve SWB by recommending
clever choices. It is however not clear how to approach design of
such technology. What are the challenges and possible solutions?</p>
      <p>The novel contribution of this paper is related to meta-analysis of
the literature in behavioral sciences related to SWB and
demonstration of how developments in this area enable design of
new recommender systems for personal finance. We aim not just to
identify new opportunities but also foresee and analyze major
difficulties associated with designing a recommender system for
application in personal finance that helps to optimize spending in
terms of savings and SWB. Our analysis will be complemented with
discussion of approaches towards overcoming these difficulties and
further implications. We hope that it will help to initiate discussion
and provoke thoughts on new research directions in the areas of
personal finance and recommender systems.</p>
    </sec>
    <sec id="sec-2">
      <title>2 SUBJECTIVE WELL-BEING</title>
      <p>A brief review of the literature on consumption and happiness is
necessary to demonstrate the current state of affairs in this area. The
review will help to understand what are the current developments in
social sciences and what input they can provide in design of
recommender systems for personal finance.</p>
      <p>We first propose to look at how psychologists approach
measurement of SWB. Data on SWB usually consists of self-reports
that reflect what people say about themselves when asked a
particular set of questions [6]. There are a number of well-known
surveys on happiness that are regularly conducted in several
countries. They include British Household Panel Survey, European
Social Survey, German Socio-Economic Panel, and the World
Values Survey. Many researchers apply data from these panels in
their work. An alternative to using data or question formulations
from the widely recognized surveys is independent collection of
data. This alternative often needs to be exploited when new
hypotheses cannot be confirmed or rejected using existing data sets.
It is not surprising that research on happiness is almost exclusively
based on data collected with questionnaires. It seems that currently
there is no better way of finding out how much individuals enjoy
their lives than asking them questions.</p>
      <p>Is it possible to sustainably increase SWB or this pursuit is futile?
This is a point of debate between psychologists. Historically, it was
considered that every person has a genetically determined set point
for happiness and people tend to fluctuate around their baselines
during lives [7]. Also, there is a concept of hedonic treadmill [8] that
implies temporality of any gains in SWB. The argument behind this
concept is that individuals always adapt to new situations or
circumstances and their effect quickly diminishes. However, there is
some recent evidence that SWB can be sustainably enhanced by
practicing intentional activities [9]. Intentional activities are any
actions in which people choose to engage. Not every activity suits to
every individual. People have different psychological profiles and
different strategies of intentional activities need to be applied.
Examples of intentional activities include committing acts of
kindness and practicing grateful thinking. These findings are
important in the context of recommender systems because they
indicate that cognitive or behavior interventions suggested by
intelligent technological systems may lead to sustainable changes in
well-being.</p>
      <p>
        One of the findings from consumer psychology that we have
already mentioned earlier is that high income is not always a recipe
for a happy life [4]. More does not mean better and an individual
need to be able to make right choices in the quest for happiness [
        <xref ref-type="bibr" rid="ref20">10</xref>
        ].
There are advocates of low-consumption lifestyles whose points of
view are supported by outcomes of this research [3]. They argue that
after a certain threshold increase in consumption does not make
much sense and people ought to focus on different goals or values.
However, it is not clear if low-consumption lifestyles will become
mainstream.
      </p>
      <p>Research in behavioral science demonstrated that people often
make mistakes in forecasts about their own emotional states in the
future [11]. There is a number of known prediction biases such as
durability bias or impact bias [12]. Due to the biases, individuals
tend to anticipate different duration and intensity of emotional
feelings. As a result of such forecasting mistakes people sometimes
put too much effort in pursuing goals that will not make them happy.
From our point of view, biases in affective forecasting seem to be
particularly suitable for being corrected by recommendations from
intelligent systems for managing personal finance.</p>
      <p>
        The last piece of research from behavior sciences that we are
going to consider in this brief review is related to types of purchases
and hedonic return. It was demonstrated that material and
experiential purchases lead to different profiles of satisfactions [
        <xref ref-type="bibr" rid="ref18">13</xref>
        ].
Consumers seem to consistently derive greater happiness from
buying experiences than from tangible or material goods. This is
another example of knowledge about SWB that is widespread
between academics but not commonly applied in the real life.
      </p>
      <p>From our analysis it is evident that science has accumulated some
interesting findings about SWB generally and specifically with
application to the consumption domain. We argue that now may be
a good time to start exploiting this knowledge and attempt to design
recommender systems that help to identify gratifying purchases.</p>
    </sec>
    <sec id="sec-3">
      <title>3 RECOMMENDER SYSTEMS</title>
      <p>Next, let us have a look at the state of the art recommendation
systems in personal finance. The number of services providing
intelligent recommendations has significantly increased during the
last decade. The research on improvement of recommendation
algorithms is being actively expanded [14]. Also, academics began
inquiry into user experience with recommenders [15] by addressing
the issues related to transparency of recommendations and trust of
users to the system.</p>
      <p>The majority of recommender systems reported in the literature
work for a specific category of goods or services. For instance, they
can support users in choosing a movie or a book. There are also
cross-domain recommenders that enable support of personal
decision making across different categories of goods [16], [17]. The
research in the area of cross-domain recommenders seems to be the
most relevant for the task of building a recommender for shaping
spending in terms of SWB because decisions about the best
purchases in terms of satisfaction and enjoyment usually require
comparing alternatives from different domains. Recommender
systems are usually deployed on the side of a company that is
offering goods or services (e.g., on an e-commerce website) with the
main motivation to increase sales. However, in the case of
recommendations with regard to happiness and satisfaction, it seems
to be more appropriate if a recommender system is run on devices
belonging to an individual who receives the recommendations. Since
we talk about a recommender system for personal finance, it will be
best if a personal finance manager and a recommender engine are
integrated in a single application. The main advantage of the
integration is that the recommender system will receive data
regarding consumption in real-time. So, it is necessary to review
what are the latest advances in the area of personal finance.</p>
      <p>Nowadays, we witness how the modern technology is changing
the way people manage their personal finance. Ubiquitous
computing has triggered an appearance of personal informatics
systems that support people in collecting and reflecting data on their
finance [18]. Such tools enable individuals to aggregate financial
information, track transactions, create budgets, and set up goals [19].
One of the examples of a digital system for managing personal
finance is Mint.com. Users of modern tools for managing personal
finance benefit from precise information about their money and
convenient interfaces for collecting this data [20]. These instruments
help to optimize spending in the dimension of wealth. This approach
for managing money is clear and well-established. However, it does
not take into consideration the dimension of pleasure or happiness
with regard to how the money is or should be spent.</p>
    </sec>
    <sec id="sec-4">
      <title>4 PROBLEMS</title>
      <p>Based on the review of modern systems for managing personal
finance and a variety of recommender systems for different domains
it is evident that there is no solution that would enable people to
budget their spending in accordance with overall enjoyment of
consumption. However, our analysis of the literature about SWB
indicates that the latest finding enable design of such recommender
systems. Now, let us analyze what are the challenges in development
of recommender systems for personal finance that take into account
enjoyment of consumption and identify potential opportunities to
overcome them. We will not attempt to present an exhaustive list of
problems but rather mention the most challenging and interesting
ones.
4.1</p>
    </sec>
    <sec id="sec-5">
      <title>Happiness and Consumption</title>
      <p>All recommender systems operate based on underlying models that
enable them to forecast what items a person is likely to enjoy or be
interested in. If one is to approach the problem of designing an
intelligent recommender system that guides users towards smarter
and more enjoyable purchasing decisions, it is necessary to know
how individual purchases contribute to the overall happiness in the
domain of consumption. In other words, one needs a model
describing relationships between spending and happiness. The
problem of obtaining such a model probably needs to be tackled by
academics from behavioral sciences or human-computer interaction
because it requires conduction of user studies expanding our
knowledge about SWB and consumption.
4.2</p>
    </sec>
    <sec id="sec-6">
      <title>Measurement of Enjoyment</title>
      <p>Another challenge in building recommender systems for allocation
of personal finance is understanding how happy a user is with a
particular purchase. An ability to quickly receive this information is
crucial for performance of the recommender because it enables to
identify inaccurate forecasts and build a knowledge graph for
generation of next forecasts. The most straightforward approach
towards measuring how happy a user is with a particular purchase is
asking them questions. It is very similar to what researchers of
happiness have been doing so far. However, when it comes to
recommender systems used in a real life, asking questions about
purchases is associated with certain difficulties. First, they are likely
going to be intrusive and users may feel annoyed by the questions.
Second, it is necessary to understand the context and know when is
the best time to ask a question. For example, consumption of certain
categories of goods (e.g., tickets for holidays) is delayed until some
time in the future or can be continuous over a period of time. In such
cases, the system will need to forecast when is the optimal time for
measuring enjoyment of a purchase.
4.3</p>
    </sec>
    <sec id="sec-7">
      <title>Meaningful Advice</title>
      <p>The importance of capability to provide meaningful and persuasive
feedback cannot be overestimated in the domain of recommender
systems. Even a very accurate recommendation generated by a
system can be of low value for a user if it is not communicated or
presented in a way that encourages the user to trust the
recommender. This also applies to recommender systems that
attempt to understand emotional experiences associated with
purchases and provide an advice about spending in terms of its
affective value. Perhaps, the aspect of designing a trustworthy user
interface is even more significant when it comes to emotional
experiences because people will not believe that a machine is able
to understand their feelings and recommend purchases that will
make them feel better. For this reason, a major challenge for a
recommender system is not just forecast items that are likely to
enhance SWB of users but also to intelligently present the
recommendation. Since the recommendations are related to the area
of personal finance, it is interesting to explore possibilities of
integrating feedback into modern payment interfaces. For instance,
a recommender system might communicate a warning that a
potential purchase is going to be a waste of money by providing
subtle feedback when a user is considering committing a transaction.
The users might not trust it from the first time but, if the warning
turned out to be correct, they are likely to pay more attention in the
future.
5</p>
    </sec>
    <sec id="sec-8">
      <title>METHODS AND APPROACHES</title>
      <p>It is proposed to approach the first problem outlined above (4.2)
through a number of quantitative experiments with individuals. The
goal of these experiments will be to see how their happiness in the
domain of consumption is related to past emotional experience with
certain things and services that they purchased. The experiments will
require collection of data about psychological backgrounds of
participants that will help to see how personality traits influence
consumption and SWB. Next, it will be necessary to record
experiences of the individuals using either self-reports or techniques
of affective computing [21]. The latter approach can potentially
enable researchers to obtain objective data about emotional states as
opposed to subjective data from questionnaires.</p>
      <p>The techniques of affective computing [22] can also be valuable
for approaching the second problem that we outlined. Indeed, if a
recommender system can receive real-time feedback about
enjoyment of consumption using recordings of physiological signals
that indicate specific emotional states, it will be an efficient solution
to the measurement problem. In this case, there is no need to bother
users with questions and the system can receive continuous feedback
on enjoyment of a particular purchase. Although automatic analysis
of affective data eliminates the necessity of using questionnaires, the
problem of understanding the context knowing when to measure
remains. One possible solution is to use additional environmental
data such as location and agenda if users authorize the recommender
system to access them.</p>
      <p>The third problem that we considered in this paper is related to
presentation of feedback from the recommender system. As we
wrote earlier, it is likely that users will not have confidence in the
recommendations provided by the system because they will concern
very sensitive aspects such as feelings and SWB. People strongly
prefer basing affective predictions on their own mental simulations
of future events or purchases rather than relying on previous
experiences of other people. Even worse if forecasts of enjoyment
need to be based on feedback from a machine. However, since
information about how much complete strangers enjoyed an
experience could help significantly improve forecasts, it is necessary
to use and present it in a persuasive way. The research on
recommender systems has already identified some clever ways of
making recommendations look more trustworthy. For example, by
presenting users how a system came to a particular conclusion or
mentioning interests that two individuals have in common. The best
way to approach this problem is to evaluate different ideas of
communicating recommendations in qualitative user studies that
will shed light on possibilities for increasing credibility of the
feedback.</p>
    </sec>
    <sec id="sec-9">
      <title>6 IMPLICATIONS</title>
      <p>Not just technology but also people themselves do not understand
very well how things work in the realms of happiness and SWB. The
implication from the analysis presented in the paper is that there are
many areas for further investigation in the field of recommender
systems for personal finance. Moreover, this work can hardly be
done by people from one discipline. Ideally, a joint effort is required
from researchers with backgrounds in behavioral science, computer
science, recommender systems, and human computer interaction.
Another implication is that research in engineering disciplines can
potentially drive and contribute to the inquiry in behavioral sciences
by developing systems for collection of data that will help to
advance knowledge about SWB.</p>
    </sec>
    <sec id="sec-10">
      <title>7 CONCLUSION</title>
      <p>In this paper, we identified new opportunities for the research related
to recommender systems in personal finance and analyzed the latest
developments in the areas of SWB and recommender systems that
are relevant to these opportunities. We argued that it is a good time
to attempt design of recommenders that aim to optimize happiness
in the domain of consumption. Following the analysis, important
problems concerning development of such recommender systems
were discussed. They included understanding of relationship
between purchases and SWB, measurement of enjoyment, and
credible presentation of recommendations. Then, possible solutions
were suggested, and finally, we briefly outlined implications of our
analysis. Being happy is one of the most important goals of people
but unfortunately they often make inaccurate forecasts about
hedonic value of events in the future and spend their money on
things that do not make them happy. We demonstrated that advances
in research on recommender systems have a potential to enhance
SWB of individuals.</p>
    </sec>
    <sec id="sec-11">
      <title>ACKNOWLEDGEMENTS</title>
      <p>This project has received funding from the European Union’s
Horizon 2020 research and innovation programme under the Marie
Sklodowska-Curie grant agreement No 655723.
[21]
[22]</p>
    </sec>
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