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  <front>
    <journal-meta />
    <article-meta>
      <title-group>
        <article-title>Risk "a ention" or "adventure": A alitative Study of Novelty and Familiarity in Music Listening</article-title>
      </title-group>
      <contrib-group>
        <contrib contrib-type="author">
          <string-name>Vikas Kumar</string-name>
          <email>kumar093@umn.edu</email>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Music Recommendation</string-name>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>User Preferences</string-name>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Qualitative Study</string-name>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Novel Versus Familiar</string-name>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <aff id="aff0">
          <label>0</label>
          <institution>Sabirat Rubya Joseph A. Konstan University of Minnesota GroupLens Research Minneapolis</institution>
          ,
          <addr-line>Minnesota</addr-line>
          ,
          <country country="US">USA</country>
        </aff>
      </contrib-group>
      <pub-date>
        <year>2018</year>
      </pub-date>
      <abstract>
        <p>While recommendations systems have shown great improvements in generally predicting relevant items, they still face challenges in achieving the delicate balance between novel and familiar options. Existing works in pursuit to address the challenge have focused on the activity logs and algorithms while largely ignoring the userspeci c needs and challenges in the balance users seek between novelty and familiarity. As a result, the assumptions imposed on user actions based on activity logs are limited and could lead to misinterpretation of users' needs. To better understand user needs, in this paper, we study users engaged in online music listening activity to understand users' interpretations and rationales in their novel and familiar music selections. We show that a combination of factors, both explicit and implicit, such as boredom, need of attention, risk of a bad selection; that play in uential role in users' novel and familiar music selections. We discuss the ndings and the implications for user interactions and user modeling that could help better understand what, when, and how users seek the balance between novelty or familiarity in their recommendations.</p>
      </abstract>
    </article-meta>
  </front>
  <body>
    <sec id="sec-1">
      <title>INTRODUCTION</title>
      <p>
        The giant ecosystems of music providers, such as Spotify, Apple
Music, Pandora, Amazon Music, etc. boasts abundance in choices
of content to attract users (e.g. all the music you want in one place)
creating tiers of content access for a variety of scenarios [
        <xref ref-type="bibr" rid="ref9">9</xref>
        ]. While
these options promote variety and freedom in choice for users in
aim to provide better experience, they also pose a challenge to users
who feel paralyzed and confused with an overwhelming number of
choices [
        <xref ref-type="bibr" rid="ref37">37</xref>
        ].
      </p>
      <p>
        Realizing that vast collection of content is both challenging [
        <xref ref-type="bibr" rid="ref41">41</xref>
        ]
and limited in their ability to provide great user experience [
        <xref ref-type="bibr" rid="ref36">36</xref>
        ],
content providers have adopted more subtle and distinct
interpretations of users’ taste in form of playlists [
        <xref ref-type="bibr" rid="ref46">46</xref>
        ], radio stations [
        <xref ref-type="bibr" rid="ref27">27</xref>
        ],
etc using popular recommendation algorithms. These algorithms
based on historical consumption data from the action logs strive to
achieve the delicate balance between helping users discover new
music versus helping users nd familiar well known options [
        <xref ref-type="bibr" rid="ref19">19</xref>
        ].
      </p>
      <p>
        The existing techniques, however, in their pursuit to nd the
balance have largely ignored the user-speci c needs. For instance,
a user might nd comfort in familiar choices at times whereas
could solicit the excitement or delightful surprise from novel or
previously unseen options. While prior works [
        <xref ref-type="bibr" rid="ref25 ref28 ref30">25, 28, 30</xref>
        ] based on
online music activity logs demonstrated that understanding users’
consumption of novel and familiar options in previous sessions
play a critical role in interpreting users’ needs for novelty, the
insu cient context about users’ intent in activity logs makes the
assumptions imposed by previous methods on what users listen
to, to be misinterpreted. For instance, a user who likes jazz and
chooses to listen to a new jazz album could do so for variety of
reasons, such as the user wants to catch up on a new album he/she
has not listened to yet, is bored with his or her existing selection,
or has discovered an artist from a recent jazz event, a friend, or
online media. These factors thus play critical role in users’ selection
of music and the balance they seek in the amount of novelty or
familiarity in their music.
      </p>
      <p>
        As a result, in this paper, we use a qualitative approach to study
users while they engage in music listening activity to understand
what and how they balance between the novelty and familiarity in
their music selection. We use the Contextual Inquiry (CI) method
where one gathers information about users while they perform
their tasks in the given context. This approach provides a medium
that allow users a conversation to re ect upon and provide
selfinterpretation of their actions for better explanation [
        <xref ref-type="bibr" rid="ref21">21</xref>
        ].
      </p>
      <p>Through our analysis of about 800 codes generated from 14 such
conversations, we provide insights into user actions and explore
answers to the following three research questions:</p>
      <p>RQ1: What do users choose? How do users choose? And
when and why do they choose to explore novel or familiar
selection?
RQ2: What explicit or implicit factors in uence users’
choices in listening to familiar or novel music and why?
RQ3: What are the common challenges that users face
while seeking familiar or novel music to listen to?</p>
      <p>
        We identify multiple factors — such as the e ort in nding new
music, the risk of a bad choice, the potential loss of attention due
to new stimuli, boredom from existing selection, the excitement
to explore, as well as the implications of mere exposure [
        <xref ref-type="bibr" rid="ref6">6</xref>
        ] from
external sources — for the balance participants sought in novelty
and familiarity in their music selection. We conclude with the design
implications of our ndings and outline the factors we believe
belong in a user model, including when, how, and for whom to
balance novelty and familiarity in music recommendation.
2
      </p>
    </sec>
    <sec id="sec-2">
      <title>RELATED WORK</title>
      <p>
        Music is considered more ubiquitous than many other media of
consumption, such as movies, books, photos, etc. While some view
choosing music to listen to as an expression of free will and
mundane [
        <xref ref-type="bibr" rid="ref45">45</xref>
        ], music choice is better understood as a product of
interlinked social, environmental, cognitive, and biological factors [
        <xref ref-type="bibr" rid="ref2 ref38">2, 38</xref>
        ].
Several common-day tasks involve music, such as walking, cooking,
cleaning, working, and relaxing, which have their own complex
sources of meanings and emotions [
        <xref ref-type="bibr" rid="ref45">45</xref>
        ]. Various eld and lab
studies have found multiple reasons why users listen to music, such as,
to manage mood [
        <xref ref-type="bibr" rid="ref33">33</xref>
        ], to create social identities [
        <xref ref-type="bibr" rid="ref18">18</xref>
        ], or to provide
a distraction from their surroundings [
        <xref ref-type="bibr" rid="ref15">15</xref>
        ] etc.
      </p>
      <p>
        However, as online music services grow in popularity, the
listening behaviors of people are also changing [
        <xref ref-type="bibr" rid="ref31">31</xref>
        ]. The ease of
online-streaming, availability across platforms1, voice-assistants23,
and the inherent psychological and emotional bene ts of
listening [
        <xref ref-type="bibr" rid="ref15 ref43">15, 43</xref>
        ] have made music more accessible and personal to users.
These systems follow listeners’ trail and similar users’ music choices
to estimate the likelihood of suggesting a similar but new music.
However, even with huge amounts of user data, it can often be
challenging to truly understand listeners’ motivations for their music
choices. The data does not imply why listeners behave or listen in
unique ways, especially how and why users seek comfort in their
selection at times and the excitement to explore new music at other
times.
      </p>
      <p>
        The challenge to nd the delicate balance between novelty and
familiarity is critical to recommendation systems [
        <xref ref-type="bibr" rid="ref23 ref51">23, 51</xref>
        ]. An
overemphasis on novelty in recommendations, for instance, can lead
to distrust and frustration [
        <xref ref-type="bibr" rid="ref13">13</xref>
        ], whereas an under-emphasis on
novelty can lead to boredom and dissatisfaction [
        <xref ref-type="bibr" rid="ref19 ref8">8, 19</xref>
        ]. As a
result, plenty of approaches exist, such as topic-diversi cation [
        <xref ref-type="bibr" rid="ref51">51</xref>
        ],
item-taxonomy [
        <xref ref-type="bibr" rid="ref47">47</xref>
        ], or declustering [
        <xref ref-type="bibr" rid="ref49">49</xref>
        ], to introduce novelty or
diversity in recommendation lists.
      </p>
      <p>
        The newer deep machine learning systems paired with the huge
amounts of data are shown to continuously update and change the
behavior of a product to match the expectations of users [
        <xref ref-type="bibr" rid="ref11">11</xref>
        ]. While
the machine learning based recommendations are most likely the
only way to e ciently scale music recommendation for millions of
users, they also push the focus to infer user preferences from mining
the data and overlook user-speci c needs in the system. As a result,
they impose interpretations based on activity logs without su cient
context of why users make the choices they do. In this work, we
therefore take the qualitative approach to better understand
userspeci c factors to interpret their actions while they engage in music
listening activity.
3
      </p>
    </sec>
    <sec id="sec-3">
      <title>METHOD</title>
      <p>
        To study the factors in user actions while they listen to music, we
use the contextual-inquiry (CI) method. It is a qualitative approach
to obtain information by observing and interviewing participants
while they perform the task in their everyday environment. This
method, adapted from eld research techniques in psychology [
        <xref ref-type="bibr" rid="ref12">12</xref>
        ],
sociology [
        <xref ref-type="bibr" rid="ref17">17</xref>
        ], and anthropology [
        <xref ref-type="bibr" rid="ref40">40</xref>
        ], has shown to be e ective in
gaining better insights and understanding of user actions in online
media consumption [
        <xref ref-type="bibr" rid="ref10 ref26 ref7">7, 10, 26</xref>
        ].
1pandora.com/everywhere
2spotify.com/us/googlehome
3spotify.com/us/amazonalexa
      </p>
      <p>
        Compared to other qualitative methods such as surveys and
questionnaires, contextual inquiry does not su er from recall bias.
Surveys and questionnaires assume that users know why they
performed a task or what they needed to complete a task. However,
while engaged in a task like music listening, people do not
necessarily re ect on what they are listening to, making it di cult to
form meaningful interpretations of user actions without the
context [
        <xref ref-type="bibr" rid="ref42">42</xref>
        ]. Instead, CI is e ective at uncovering tacit knowledge [
        <xref ref-type="bibr" rid="ref21">21</xref>
        ].
It allows participants to engage in dialogues to re ect on and shape
the interpretations of their actions while being in the context of
the task.
      </p>
      <p>Due to the qualitative nature of the study, we chose a small
number of participants to conduct in-depth inquiries with while
they listened to their music in their everyday environments. We
describe the participants, procedure, analysis, and platforms we
studied in the following sections.
3.1</p>
    </sec>
    <sec id="sec-4">
      <title>Participants and Procedure</title>
      <p>Participants were recruited through informational posters in public
places like co ee shops, university libraries, and private workplaces
in the cities of Minneapolis and Seattle. Although participation was
voluntary, each participant was required to meet the minimum
criteria as follows: (a) must be 21 years or older, (b) must listen to
music at least 2-3 times in a month, (c) must be comfortable sharing
music experience in an everyday environment, and (d) must be able
to schedule two 1-hour sessions.</p>
      <p>
        Interested participants contacted researchers via email and were
then referred to ll out an online questionnaire to con rm their
eligibility. As required by the Institutional Review Board (IRB) [
        <xref ref-type="bibr" rid="ref24">24</xref>
        ],
in the questionnaire participants reviewed the details and
requirements of the study, including their eligibility with regards to their
age, their daily music listening patterns, their preferred music
platforms, and their preferred times and locations to schedule the
interviews. Each participant was compensated with a $30 Amazon
gift card upon completion of the nal session.
      </p>
      <p>
        Based on responses to the questionnaire, we used the “purposive”
sampling approach, in which we include participants from multiple
platforms, di erent professional backgrounds, and with di erent
listening patterns such that a variety of users are represented to
con rm or challenge emerging patterns [
        <xref ref-type="bibr" rid="ref32">32</xref>
        ].
      </p>
      <p>Participants were then invited to schedule two 1-hour sessions,
each separated by several days and scheduled at di erent times of
the day to understand users explanations under di erent contexts,
while keeping the location of the interview the same. During each
session, for the rst 30 minutes participants picked music to listen
to while we took notes, with no interruption to the user. In the
following 30 minutes, we asked users a set of questions to allow
users to explain and re ect on their actions.</p>
      <p>Participants’ consent was taken during each interview.
Participation was voluntary and users were given a choice to stop the
interview at any time of the observation session. We noted users’
actions, such as browsing, searching, clicking, skipping, and
shufing, while they picked their music to listen to. As music can be
a background process while the user focused on other tasks like
writing, reading, browsing, etc., we asked users to install Last.fm
scrobbler4 (using their own account and consent) to enable song
tracking for the music they listened to during the session. This also
helped avoid any interruptions while a user was engaged in his/her
task. They were reminded at the end of session to uninstall the tool.</p>
      <p>
        Table 1 provides a description of the participants, their
backgrounds, and their music listening patterns. A total of 7
participants were selected and 14 interviews (2 for each participant) were
conducted in the study. Participants included in the study were
professionals from di erent backgrounds and included one student
(P7). Participants had varying degrees of interest in music with two
avid listeners (P2 and P6), two with music backgrounds (P1 and P4),
and three casual listeners (P3, P5, and P7). While our participants
did not span across a wide age range, they do fall within the age
group of 22 to 35 year olds; the age group that has most embraced
online music streaming services [
        <xref ref-type="bibr" rid="ref37">37</xref>
        ]. Among the 7 participants,
four participants were observed while at their workplaces (o ces)
(P1, P2, P3, P4), one while at home [P6], one while working at a
public place (library) (P7), and one during transit (P5).
3.2
      </p>
    </sec>
    <sec id="sec-5">
      <title>Analysis</title>
      <p>
        To assess users’ responses, we had to determine what songs were
familiar to users and which were novel. However, this was
challenging due to two reasons: 1) the de nition of novelty as understood by
a recommendation system is not how users perceive novelty, and
2) every participant was likely to have a subjective interpretation
of novelty in their selection. For example, a song that a user really
likes but has not listened to in awhile can be novel to the user [
        <xref ref-type="bibr" rid="ref1">1</xref>
        ].
Oba et al. in their study of nostalgic experience have shown that
items from the past that a user likes but has not seen or consumed
recently induces nostalgia in the same parts of the brain that are
active during novel exposure [
        <xref ref-type="bibr" rid="ref39">39</xref>
        ]. As a result, we did not ask
direct questions about users’ familiarity or novelty with their music
selection. Instead we asked if the music chosen was (a) listened to
recently, that is within the last few weeks to a month, which we
consider as familiar, or (b) listened to in the past but not in awhile
or never listened to before, which we consider as novel in this study.
This de nition of novelty helps capture the inherent property of
repetition in music, which is well known to delight users [
        <xref ref-type="bibr" rid="ref3 ref34">3, 34</xref>
        ].
      </p>
      <p>
        After the completion of the interviews, the 14 hours of voice
recordings (two hours for each of the 7 participants) were
transcribed into open-codes to capture the individual viewpoints,
rationales, and interpretations users shared during the sessions. About
4https://www.last.fm/about/trackmymusic
800 open codes were generated, with each code being reviewed by
two researchers. The number of open codes was then signi cantly
reduced in the process of memoing and categorizing using a
constant comparison described in a nity mapping [
        <xref ref-type="bibr" rid="ref44">44</xref>
        ]. In the process,
every code was compared to others and positioned to re ect its
a nity to an emerging topic and the research questions. We used
the topics to understand the common themes in responses and
actions of di erent participants to answer the research questions.
We also captured themes with disparate responses or opinions to
gather divergent user perspectives.
3.3
      </p>
    </sec>
    <sec id="sec-6">
      <title>Platforms</title>
      <p>Here we discuss the three platforms (Spotify, Apple Music, and
Pandora) used among our participants. Although these platforms serve
the similar function of streaming online music, it is critical for this
study to understand the di erences and the types of services each
provides. For instance, Spotify and Pandora provide a freemium 5
service, while Apple Music provides only a paid subscription-based
service. Spotify and Apple Music both provide music interactions
that include lists of curated playlists, personalized playlists,
album/artist suggestions, as well as lists of new releases and top
charts. Until very recently, Pandora only provided a list of stations
that users could create, or they could choose from existing
systemsuggested stations based on artist, track, mood, genre, etc. Pandora
also provides a few niche options for users, such as selecting I am
tired of this track! to skip a track, compared to only thumbs down
or next track option in the other two platforms. Finally, all three
platforms boast an abundance of music options for users with their
premium subscriptions, which each of our participants had for
their choice of platform. As a result, each session during the study
was ad-free and included all services that the individual platform
provides.
4</p>
    </sec>
    <sec id="sec-7">
      <title>RESULTS</title>
      <p>We now discuss results from the analysis. We rst discuss the
choices participants made and their intents before listening,
followed by key factors identi ed as common themes across
participants that a ected their choices of novel and familiar music. Finally,
we conclude with key challenges common across participant
responses while they sought novel or familiar music.
4.1</p>
    </sec>
    <sec id="sec-8">
      <title>Choice of music: What did participants listen to?</title>
      <p>We recognize two speci c cases in choices participants made to
select music to listen to — they either (1) picked music they knew
they wanted to listen to, that is, a speci c artist, an album, or a band
or (2) picked music for which they didn’t have a speci c artist or
album in mind but instead had a general preference for the kind of
music they wanted to listen to. In the latter case, their choice was
speci cally to align with speci c needs in form of mood, attention,
etc. For instance, “smooth Jazz instruments that won’t interfere
with my studies.” The participants’ sessions for each case is shown
in Table 2. We discuss both the cases and how participants arrived
at their choices in this section.
5A type of service in which a platform provides the music free of charge, but some
premium features like high-de nition music or ad-free music are available for a charge.</p>
      <p>Case 1: When participants knew the speci c music they wanted to
listen to, they mentioned choosing albums or songs by an artist they
had recently discovered. Participants mentioned that discovering
music they found interesting but di erent from what they usually
listened to was mostly in uenced by external sources, such as
“found on a TV show,” “saw it trending on BBC Radio One,” etc.</p>
      <sec id="sec-8-1">
        <title>P4: “I found this artist from a TV show and liked</title>
        <p>one of the songs I listened to on YouTube. I liked
the music and wanted to listen to more of that
music on Spotify.”</p>
      </sec>
      <sec id="sec-8-2">
        <title>P2: “I found this DJ from BBC Radio One, which</title>
        <p>often releases collections of new songs that I like
to explore and listen to to see if I like them.”</p>
        <p>Participants mentioned that in some cases discovery was not
only limited to new artists or new bands they had never heard
before, but also included “new songs they have not yet listened to
by a familiar artist” and how mentions from friends or news media
helped them nd this music.</p>
      </sec>
      <sec id="sec-8-3">
        <title>P4: “I heard that a new release is coming up from</title>
        <p>this band, which reminded me of my previous
favorite album from the band. I just wanted to
go back to music by the artist before the new
release.”</p>
      </sec>
      <sec id="sec-8-4">
        <title>P1: “This remix recently came and my friend</title>
        <p>shared it with me. I really like the remix, although</p>
      </sec>
      <sec id="sec-8-5">
        <title>I generally prefer to listen to the original itself.”</title>
      </sec>
      <sec id="sec-8-6">
        <title>P2: “A new song came from the artist recently</title>
        <p>and my friend, who I believe has a good taste in
music, told me about it. So I wanted to listen. I
like the song and will likely listen again.”</p>
        <p>A few participants (P4, P1, and P2) also mentioned the role
external events and sources play in reminding them of an old album
or an artist they had not listened to in awhile (P4: “A game I was
playing last night had a tune in the background that reminded me of
the band I wanted to listen to today...” ).</p>
        <p>There were a few sessions (P4-R1, P2-R1) during which
participants knew what they wanted to listen to but did not choose
anything di erent from what they were currently listening to.
Participants chose to continue with an album they were recently
listening to or a playlist they had recently curated or that had a list of
songs large enough that they had not listened to the entire playlist
yet. When asked about the concern of repetitions, participants
mentioned using shu e to add some uncertainty to the order of songs
and that they didn’t mind if some songs repeated over multiple
sessions.</p>
      </sec>
      <sec id="sec-8-7">
        <title>P2: “I wanted to listen to the playlist I curated</title>
        <p>last week. I am excited about the playlist and so</p>
      </sec>
      <sec id="sec-8-8">
        <title>I wanted to listen to it again today"</title>
      </sec>
      <sec id="sec-8-9">
        <title>P4: “Spotify created this year-end playlist that I</title>
        <p>have been listening to for the last couple of days.</p>
      </sec>
      <sec id="sec-8-10">
        <title>Although I have listened to most of the songs in</title>
        <p>the list, I will continue listening for some time, as</p>
      </sec>
      <sec id="sec-8-11">
        <title>I don’t remember listening to the same songs due to the sheer size of the playlist."</title>
        <p>Case 2: When they did not have a speci c artist, song, or album
they wanted to listen to, participants cited that their music
selection was to align to the speci c needs of that hour. For instance,
participant P7 cited the bene t of selecting a jazz playlist she had
listened to earlier in the week to avoid the divided attention between
music and an assignment that needed focus. (P7: “Was looking for
something that I can play while doing my assignment and liked how
smooth this playlist is, as it has a more monotonous tone that helps
me focus.” ).</p>
        <p>In another instance, some participants (P6-R2, P7-R1) mentioned
their desire for a calming and relaxed mood as a reason for their
selection.</p>
      </sec>
      <sec id="sec-8-12">
        <title>P6: “I think I selected the playlist because I was</title>
        <p>looking for something easy and warm for the
mood. It is rainy outside . . . this just ts the
atmosphere I guess. I like some songs in this playlist
and often choose this playlist to relax.”
P7: “I wanted to be in, like, a good mood as I
have a busy night, so I wanted to listen to
something happy, upbeat, and generally kind of light,
and this is supposed to be happier than other
playlists. Also, Christmas is soon and I am a big
fan of Christmas music, so I’m kind of getting in
a holiday spirit."</p>
        <p>In the case that they didn’t have a speci c kind of music in mind
to listen to, participants also relied on recommendations from the
music streaming platform. They picked an album or playlist that
they were very familiar with but had not recently listened to (P5:
“Saw the album in the suggestions and I had not listened to the artist
(Kendrick Lamar) recently. I really like his songs."). The participant
mentioned the induced boredom from his current selection as a
reason to choose something di erent (P5: “Didn’t want to continue
what I was listening to as I have been listening to it for few days
now.").</p>
        <p>Summary: Participants found the music they listened to in
various ways. Among these cases, we recognize that the participants’
choice of music, and speci cally music di erent from what they
were listening to, was due to external events or sources. They
mentioned they “discovered an artist from social [media] mentions,”
they found “new releases from a familiar artist,” their choice was
an “old favorite that I haven’t listened to in a while,” they had seen
a “news story that reminded me of a favorite”, or they were simply
“bored from their current selection.” Each of these reasons highlight
the users’ excitement to either discover a new artist or rediscover
an old favorite from an external source. Whereas for participants
who chose to continue with music they had been listening to, they
primarily cited wanting “to continue listening to an existing playlist
that I have not nished yet,” to listen to an “album or list that aligns
with the desired mood,” or to nd “a playlist that helps maintain
focus on the task at hand.” These users’ rationales suggest they
found comfort in listening to music they were currently listening
to instead of putting forth the e ort to nd di erent music. As
such, we observe that the participants’ selections of music were a
combination of speci c curiosity needs, moods, or desires.
4.2</p>
      </sec>
    </sec>
    <sec id="sec-9">
      <title>What explicit and implicit factors in uence users choice of music?</title>
      <p>There are some key factors we identi ed across users’ responses
for their speci c selections of music.</p>
      <p>
        4.2.1 A ention. Music is known to play a crucial role in either
aiding or distracting the attention needs of users [
        <xref ref-type="bibr" rid="ref14">14</xref>
        ]. Music one
likes can help increase focus, while music one doesn’t impedes
it [
        <xref ref-type="bibr" rid="ref22">22</xref>
        ]. Participants (six out of seven participants) mentioned that
their degree of attention between music and work play an in uential
role in their choices of music. They noted that the type of task at
hand a ects what kind of music they prefer. For example, a task that
demands high attention, such as reading to absorb new information,
versus a less attention-demanding task, such as browsing online
social media, results in di erent selections of music.
      </p>
      <sec id="sec-9-1">
        <title>P2: “I don’t like working to new music. To know</title>
        <p>whether I like an artist/song, I have to really give
it attention. Either gure out the song or do work,
can’t do both unless given an attention. As an
alternative, if at work and likes something then
will save it for later to give necessary attention."</p>
        <p>Participants mentioned that when attention needs are high, they
look for music they frequently play, citing the comfort of listening to
familiar music in helping them focus (P7: “Yes, today I was wanting
to listening something like this because I just wanted to focus and I
have a lot of stu to do. I listen to it often when I am studying and
writing"). And, when attention needs are low, they prefer listening
to new music (P2:“Okay being distracted as was in mood to discover
new songs” ). They discussed how the excitement from the new
stimuli led them quickly down a "rabbit hole" of exploring artists’
discography and other similar artists, thus taking attention away
from the task at hand.</p>
      </sec>
      <sec id="sec-9-2">
        <title>P4: “Explicitly wanted something to occupy more</title>
        <p>of my attention and listening to new music is an
easy way to do that because its a new stimuli. You
know, may be discovering a new band or artist,
that quickly go down very deep rabbit hole"</p>
      </sec>
      <sec id="sec-9-3">
        <title>P2: “I am okay being a little distracted today. It</title>
        <p>does not happen always but when it happens I
am in this way to queue up few things. Picking up
related artists from a new song I like is another
easy way but also takes the attention away."</p>
        <p>Apart from new music resulting in distraction, a couple of
participants (P3 and P6) mentioned that their past favorite music they
have not listened to recently (subset-(b) - novel) resulted in similar
distractions as it brings their attention to the parts of tunes or lyrics
they like, and the memories associated with the tunes.</p>
        <p>Participants (P4, P5, and P7) also mentioned the speci c type
or genre of music they prefer for speci c attention needs. For
example, classical or no vocals music to help them zone out from
their surroundings to focus on their work at hand (P4: “..there is
instrumental or classical that is not distracting..").</p>
        <p>To summarize, participants’ attention requirements play a unique
role in their choice of music. Participants preferred to choose music
they recently consumed with high familiarity when they know the
attention requirement of the task at hand is high to avoid
distractions, and new or forgotten music when it is low. Participants noted
that the e ort involved in selecting novel music and the risk of
bad selection are often the causes of divided attention – a possible
explanation of why familiar music help users nd comfort and ease
in their choice.</p>
        <p>4.2.2 Boredom. Participants frequently mentioned boredom as
one of the primary reasons for selecting the music they listened
to during the session. They mentioned being tired of their current
selections as primary factor in selecting music other than what
they were currently listening to. Some participants (P1, P2, and P4)
mentioned that they sought exploration and hence looked for new
music, whereas other participants (P3, P6, and P5) highlighted the
pleasure they sought in playing past favorites they had not recently
listened to, which makes them feel nostalgic and relaxed. When
asked speci cally about which novel music would they prefer, new
or past favorites, they cited the available attention and the e ort to
nd new music as the dependent factors.</p>
        <p>In addition, irrespective of whether participants chose past
favorites or new music, they commonly mentioned seeking music
from di erent genres than they were currently listening to to avoid
boredom.</p>
      </sec>
      <sec id="sec-9-4">
        <title>P1: “I feel like its harder to nd something new I</title>
        <p>could fall in love with in the genre I listened to
most. I can more easily nd something exciting
in a di erent genre that I don’t usually listen to.”</p>
      </sec>
      <sec id="sec-9-5">
        <title>P3: “I did not come across this music (I like) before</title>
        <p>as I don’t usually listen to this genre.”</p>
        <p>For some participants who were multilingual this meant
changing the language of music from what they were currently listening
to (P5: “If I get bored from this, I often go back to choose music from
language (native) other than English").</p>
        <p>4.2.3 Sheer Joy of Adventure. While being bored from current
selections was cited as a cause to select new or forgotten music,
users also cited “sheer joy of adventure” as the other reason to choose
music di erent from their current selection.</p>
      </sec>
      <sec id="sec-9-6">
        <title>P2: “ I didn’t feel like playing my older playlists.</title>
      </sec>
      <sec id="sec-9-7">
        <title>I just woke up today in discovery mood and then looked up a playlist shared by my friend and I found remix of a song that I liked and it all kicked o from there into nding more related artists."</title>
        <p>
          The users’ choices to seek new artist because of sheer joy of
adventure emphasize a limitation on the assumption of user model in
existing boredom-based novelty recommenders [
          <xref ref-type="bibr" rid="ref29 ref30">29, 30</xref>
          ]. They only
considered that tendency of user to seek novel music is dependent
on the boredom of user with current selection, however as our
participants mentioned, it could also be users’ appetite for sheer
joy of adventure.
        </p>
        <p>To summarize, boredom of participants with their current
selections in uences signi cantly what music users choose to listen to.
While users look for novel music when bored, they are likely to
explore di erent genres or languages than they were listening to.
In addition, the excitement participants sought in new stimuli is
not limited only to boredom, but also the sheer joy of exploration
that can lead users to choose novel music.</p>
        <p>4.2.4 Priming. Users choosing novel music mentioned learning
about the artist(s) from conversations with friends [P1, P2, P4], TV
shows [P5], music blogs [P2], DJs [P2], online social media [P1],
etc. In their e ort to recall the external events that a ected their
choices, participants cited sources they trust more than others. For
example, they mentioned only a few friends who they believe have
good tastes in music, TV celebrities they like, accounts they follow
on social media, and DJs from a reputed radio station, like BBC
Radio One, as sources of in uence.</p>
        <p>Apart from external events, participants also mentioned in
uence due to recommendations shown on the music platforms (P1:
“often choose new album to listen when platform (Apple Music)
suggests release of new album from one of my favorite artist")</p>
        <p>
          These events a ected users’ choice in music in ways similar to
the e ects of priming, which reinforces the notion that subtle
exposure of an entity can cause large e ects on the perceived attraction
for the entity, also referred as perceived familiarity. In social
psychology, perceived familiarity is de ned as the feeling of acquaintance
upon mere exposure to an item [
          <xref ref-type="bibr" rid="ref48">48</xref>
          ] that leads to a perceived
attraction to the item [
          <xref ref-type="bibr" rid="ref35">35</xref>
          ]. Although recommendation systems have
studied ways to model perceived familiarity of users [
          <xref ref-type="bibr" rid="ref20">20</xref>
          ], inducing
this familiarity is often bounded to user interactions within the
system [
          <xref ref-type="bibr" rid="ref50">50</xref>
          ]. These systems limit the ways to incorporate the e ects
from sources outside the system–sources in which users place a
high degree of trust.
        </p>
        <p>4.2.5 Order in the selection of music. Apart from what
participants selected, we also asked participants about their preferences
in the order of songs in the playlists and albums they chose to listen
to.</p>
        <p>Participants who chose playlists mentioned using shu e to
increase the uncertainty in the order of songs (P4: “I usually shu e
the playlist because I don’t know if this music is most played or 100th
most played, so I usually shu e if I don’t know there is speci c
ordering that is going in” ). However, even with this uncertainty, a
few participants who listened to a playlist during the sessions
mentioned the desire to listen to their favorite songs in the playlist
sooner rather than later for an “instant grati cation” (P3) of their
choice in playlist.</p>
      </sec>
      <sec id="sec-9-8">
        <title>P4: “Selected a song that I recognized I like in the</title>
        <p>playlist.”</p>
      </sec>
      <sec id="sec-9-9">
        <title>P7: “....would like to de nitely listen to my fa</title>
        <p>vorites in the mix of songs in the playlist...”</p>
      </sec>
      <sec id="sec-9-10">
        <title>P3: “....instant grati cation with your choice of</title>
        <p>music when it plays songs you are most familiar
with...”</p>
        <p>A few participants also changed the music they were listening
to during the sessions. This included responding positively to a
song, leading to queuing up a couple more songs from the artist
or other similar artists, or skipping to the next song in the queue.
Participants cited that the primary reason to skip a song is to avoid
the distraction from the tune or lyrics of the song. One participant
mentioned skipping to reach their favorite song in the playlist
sooner rather than later (P5: “I selected the playlist as I remember
one of my favorite song was in that playlist. I skipped few songs to
reach the favorite song quickly. It would have been nice to have that
song play earlier.” )</p>
        <p>Participants who listened to albums, however, cited a distinct
tendency to avoid shu ing and skipping. Participants P1 and P4
cited their rationale about avoiding shu ing as albums “represent a
statement by an artist and I respect the order the artist wants them to
be heard. I listen to whole album front to back as is and always nish
the album if halfway through” (P1), and “ I rarely shu e albums. I
know that a lot of times a band will structure albums to kind of have
an inherent ow to them. I also do not skip songs in an album even
with moderate liking.” (P4).</p>
        <p>To summarize, participants had distinct expectations of the order
for albums and for playlists. They preferred listening to an album in
the same order it was curated, whereas for playlists they preferred
to shu e the order of songs with an expectation to listen to their
favorites sooner for instant grati cation.</p>
        <p>4.2.6 User Se ings. Last but not least, participants P6 and P7
highlighted the e ects of setting or environment on their selection
of music. Participants discussed how their selection could be
different from their current choices based on location, such as the
gym, work, home, etc., and the time of day. For instance, some
participants (P2 and P7) preferred listening to mainstream
popular new releases in the evening to avoid disruptions during work
hours (P2: “Even though I really do like their music (a BBC Radio</p>
      </sec>
      <sec id="sec-9-11">
        <title>One DJ releasing a new playlist), I prefer listening to these while at</title>
        <p>home in the evening when I play more mainstream stu ” ). Similarly,
participants P1, P4, and P6 mentioned listening to non-vocals at
work and fast, upbeat pop music during workout sessions.</p>
      </sec>
      <sec id="sec-9-12">
        <title>P6: “Would not choose this music (slow and calm</title>
        <p>ing) for a workout or when thinking quickly to
match up the rhythm”</p>
        <p>Based on the observations of settings across various sessions, we
found that participants whose sessions were at the start of the day
when the focus on work is still divided selected more novel options.
However, participants whose sessions were in the afternoon when
they needed to focus more on work chose familiar music to listen to.
Other than the attention requirement, we believe another possible
explanation can be the fatigue of the day causing participants in
the afternoon to choose something comfortable without the added
e ort of nding and exploring something new.</p>
        <p>Users also highlighted that when not interacting with the
platform interface, like during workouts or driving, they prefer to pick
up music they are most familiar with and currently listening to in
order to avoid the pain of selection on the smaller screen of mobile
devices.</p>
      </sec>
      <sec id="sec-9-13">
        <title>P4: “Cause I only have a few songs or albums</title>
        <p>downloaded on my phone I listen to them (the
artist) frequently on the bus or gym and that is
one of them.”</p>
        <p>Participants also mentioned the role of mood in their selection
of music, such as upbeat music when happy versus melancholic or
calm music when occupied with a tedious task [P3, P6, P7].</p>
      </sec>
      <sec id="sec-9-14">
        <title>P7: None of the songs are favorites, but chose the</title>
        <p>album due to the mellow and calming nature of
the music.</p>
      </sec>
      <sec id="sec-9-15">
        <title>P3: Would pick up this artist or this type of music</title>
        <p>(90s Alternative Rock) when feeling melancholic,
as they remind me of teenage years.</p>
        <p>Overall, the setting during the session or the context played a
critical role in participants’ choice of music. Most of the participants
mentioned a speci c choice of music under certain settings, such as
fast and upbeat music they are familiar with during workout and
gym sessions or exploring new and trending releases during the
evening.
4.3</p>
      </sec>
    </sec>
    <sec id="sec-10">
      <title>Challenges</title>
      <p>We asked participants the explicit challenges they face when they
look for music to listen to that is di erent from what they are
currently listening to. We highlight three of these challenges that
were commonly expressed in participant responses.</p>
      <p>
        4.3.1 Too many options. Music recommenders have evolved in
many ways to help users choose music they want to listen to.
Spotify, for instance, suggests songs curated into multiple categories
for users to start listening to based on time of day, mood, genre,
recent releases, trending, etc. The multitude of choices are
appreciated by users as they help cater to di erent needs [
        <xref ref-type="bibr" rid="ref16">16</xref>
        ]. However,
participants in the study mentioned that with plenty of options,
nding what to listen to becomes harder and that “..it takes a lot
of energy to nd something new to listen to.. - P2”, while wading
through the myriad of choices. The high e ort involved in choosing
among available options was cited as a deterrent to the desire of
choosing any new music they have not heard of — “Does not want
to spend limited amount of time I have to a song that I have not heard
of” - P3.
      </p>
      <p>4.3.2 Risk of Failure. Participants mentioned the risk involved
in choosing something new.</p>
      <sec id="sec-10-1">
        <title>P1: “Discovered 3 brand new albums in 1 week</title>
        <p>but only one stuck around. Tried looking for more
popular Jazz Rock but haven’t found them
interesting.”</p>
        <p>Participants (P6, P7) mentioned the risk of mismatch of their
selection with their desired mood as another reason they avoided
selecting new music. In such cases, users preferred listening to
curated playlists in which songs are expected to be similar to a
speci c genre suitable for the mood requirement of the hour.</p>
        <p>4.3.3 Lack of trusted and accessible sources. Participants
highlighted trust as an in uence in their selection of novel music to
listen to. They relied on sources such as friends whom they believe
have good tastes in music and media they follow to help them
discover more novel music (P4: “Finding new song can be hard if don’t
have the right source.” ). A few participants (P2, P3) also mentioned
their frustration with lack of trusted sources, such as BBC Radio
One, on their preferred music listening platforms.
5</p>
      </sec>
    </sec>
    <sec id="sec-11">
      <title>DISCUSSION</title>
      <p>We conducted a contextual-inquiry study to gain insights into how
a small group of participants chose novel and familiar music, what
factors a ect their choices, and the challenges they faced while
seeking novel versus familiar music. In this section, we
summarize the insights from the study and discuss the possible design
implications for e ective recommendations.</p>
      <p>5.0.1 Balance of E ort, Risk, and A ention. Participants
mentioned the e ort involved in searching for novel music. This e ort
contrasts with the comfort they mentioned in continuing to listen
to their current music selection, or familiar music. To alleviate some
of the e ort of searching for novel music, recommendation systems
aim to introduce novel items directly into their lists of
recommendations. However, in discussing the e ort of searching for novel
music, participants also mentioned two critical factors of this e ort
that are often overlooked in the design of recommenders.</p>
      <p>First, the risk appetite of individual users. Some participants
mentioned greater appetites to explore newer unknown options
than others. In our own results in studying the appetite of users for
novel items in Chapter 2, we show that a recommender adaptive to
the individual di erences in novelty consumption is more accurate
than a traditional one-size- ts-all recommender.</p>
      <p>
        Second, the potential attention needs of users. Participants cited
how familiar music helps maintain their focus when attention
requirements for the primary task at hand are high, as well as how
exploring novel music is avoided to minimize the interruptions
in their focus-intensive tasks. This aligns with prior studies that
have shown that interruptions from peripheral tasks such as music
listening have huge impacts on the primary task at hand,
resulting in needing more time to complete the task, committing more
errors in the task, and experiencing more annoyance and
anxiety [
        <xref ref-type="bibr" rid="ref4 ref5">4, 5</xref>
        ]. Studies suggest that delaying such interruptions towards
the phases between the primary tasks causes less disruptive impact.
In music listening, these phases could be the intermittent
interactions users have with the music service, that is, when users are
distracted from their primary tasks. It is at these times that
recommendation systems could introduce or suggest novel items in lists
of recommendations.
      </p>
      <p>5.0.2 Boredom versus Sheer Joy of Adventure. Participants cited
boredom of their current selection or the sheer joy of adventure
in exploration of novel music, that is, music di erent from their
current selection. However, we noted distinct di erences in the
participants’ expertise who sought novel music to avoid boredom
versus those who sought novel music for adventure. The
participants who mentioned the joy of adventure (P1, P2, and P4) were
arguably the ones who take their music seriously, as their interest in
music went beyond just listening. These were the users who create,
curate, share, and consume music with others. Also, some of the
artists listened to by these participants were found to be more
obscure (ex: Jagga Jazzist with about 56 thousand listeners on Spotify)
than mainstream music. In comparison, the group of participants
who cited boredom (P3, P5, P6, and P7) showed more interest in
mainstream music, with preferences for artists like Kendrick Lamar,
who has about 36 million listeners on Spotify. The latter group of
participants cited reasons to nd or explore di erent music to
primarily manage mood, avoid boredom, or help achieve focus when
distractions surround them. Thus, these di erent levels of expertise
can help systems determine a more accurate appetite for novelty
for individual recommendations. For instance, the tendency of a
participant to continue with their choice of music before they again
felt the urge to shake things up was more evident in the second
group of participants, whereas the participants who cited the joy
of adventure mentioned seeking novel music more frequently.</p>
      <p>
        5.0.3 Perceived Familiarity, Trust, and Genre of Novel Choices.
Once users decide that they want novel music, the question that still
remains is how do recommenders pick from the plethora of
available options? The participants’ responses highlight three distinct
insights. First, participants’ likelihood of exposure to the music
from external sources. Participants mentioned friends, music
concerts, social media, and TV shows as some of the sources that led to
their selection of novel music. This is related to the phenomena of
mere exposure that results in an aroused curiosity and a perceived
familiarity towards previously unheard or unknown items [
        <xref ref-type="bibr" rid="ref35">35</xref>
        ].
      </p>
      <p>Second, participants interested in the discovery of new music
cared about trust in their sources of music. Participants were clear
that not every friend, event, or blog is in uential in their choices
of novel music and that trust and reputations of sources play a
crucial role. They mentioned that friends who they believe have
good tastes in music, celebrities who they like, and music blogs that
they trust, such as BBC Radio One, often led them to explore new
artists. Participants’ emphasis on trust and reputation highlights
why some new artists were more preferred than others.</p>
      <p>Third, the genre of novel music plays a critical role. On the one
hand, the group of participants who mentioned boredom as a cause
to seek novelty sought to change the genre of music (including
language for multilingual participants) from what they were currently
listening to. However, other participants who sought novel music
for sheer joy mentioned exploring new releases in the same genre
they were currently listening to. The primary di erence between
these participants from the previous group was how important they
consider music in their daily consumption. Understanding these
di erences in user consumption therefore can help recommender
systems identify if novel music to be recommended is required to
belong to a di erent genre than the user is already listening to.
5.1</p>
    </sec>
    <sec id="sec-12">
      <title>Limitations</title>
      <p>While we summarize the observations and implications from
participants’ responses, we also recognize the limitations of this study.</p>
      <p>First, we discuss limitations having to do with the participants.
Being under observation could have possibly a ected the attention
of participants who might have selected di erently without an
individual overlooking their picks. Also, by the nature of their
willingness to participate in this study, participants are likely more
comfortable expressing their thoughts than the rest of the general
population. This characteristic of participants could di erentiate
their preferences for novel and familiar music from the rest of the
general population. Finally, their recall accuracy of whether they
had listened to speci c tracks or artists in the past month could
impact the accuracy in determining familiar and novel music.</p>
      <p>Second, we discuss limitations with the study design. The
music language was chosen to be English, limiting any cross-cultural
comparison or inference from the results. Also, there is a likelihood
of implicit bias due to the selective nature of recruitment that could
limit the generalizability of the themes across the general
population. Finally, the number of participants is a small representation of
a wide and diverse range of music listeners and prohibits us from
generalizing to the larger population. However, since the study is
exploratory in nature, we do not expect this to harm the external
validity of our ndings and recommendations with a view to inspire
future work.</p>
    </sec>
    <sec id="sec-13">
      <title>6 CONCLUSION</title>
      <p>Recommender systems have become ubiquitous in many online
systems, helping users discover both new and forgotten items. As
systems grow and more diverse users join systems, it is becoming
more crucial to understand the structure and intention of
userspeci c needs to provide an engaging and satisfying experience.</p>
      <p>We conducted a contextual inquiry-based study to understand
participants’ actions and intentions while they seek novel or
familiar music in online music streaming platforms. We observed
participants while they listened to music in their everyday settings
and followed up with interviews to expand on factors, such as
attention, e ort, trust, boredom, and risks, that play a major role
in the users’ choices of novel or familiar music. We identi ed the
challenges participants faced, such as a lack of trustable sources,
an overwhelming number of choices, and the risk of a bad choice,
that drive users to stay within the comforts of familiarity and avoid
uncertain risk-rewards of novelty.</p>
      <p>In order to design e ective recommenders, we discussed the
results and design implications to emphasize the gap in the
assumptions imposed by traditional algorithms on user-speci c needs in
seeking novel and familiar items. Our results emphasize the goal of
recommender algorithms to explore user needs beyond explicit and
implicit interactions and include in the models the likelihood of the
attention needs of the user, the risk appetite of each user, and the
types of novel music users consume in their sessions. Finally, while
this work focuses speci cally on music and with limitations on
the number of qualitative observations, our ndings speak to the
challenges in mapping user needs for content providers in multiple
domains such as news, movies, books, etc.
7</p>
    </sec>
    <sec id="sec-14">
      <title>ACKNOWLEDGEMENT</title>
      <p>We would like to thank participants who agreed to share their
time and experience in the study. We also thank the anonymous
reviewers for their valuable feedback and inputs.</p>
    </sec>
  </body>
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