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  <front>
    <journal-meta />
    <article-meta>
      <title-group>
        <article-title>Personality &amp; Emotional States: Understanding Users' Music Listening Needs</article-title>
      </title-group>
      <contrib-group>
        <contrib contrib-type="author">
          <string-name>Bruce Ferwerda</string-name>
          <email>bruce.ferwerda@jku.at</email>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Markus Schedl</string-name>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Marko Tkalcic</string-name>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <aff id="aff0">
          <label>0</label>
          <institution>Department of Computational Perception, Johannes Kepler University</institution>
          ,
          <addr-line>Altenberger Str. 69, A-4040 Linz</addr-line>
          ,
          <country country="AT">Austria</country>
        </aff>
      </contrib-group>
      <abstract>
        <p>Music plays an important part in people's lives to regulate their emotions throughout the day. We conducted an online user study to investigate how the emotional state relates to the use of emotionally laden music. We found among 359 participants that they in general prefer emotionally laden music that correspond with their emotional state. However, when looking at personality traits, di erent patterns emerged. We found that when in a negative emotional state, those who scored high on openness, extraversion, and agreeableness tend to cheer themselves up with happy music, while those who scored high on neuroticism tend to increase their worry with sad music. With our results we show general patterns of music usage, but also individual di erences. Our results contribute to the improvement of applications such as recommender systems in order to provide tailored recommendations based on users' personality and emotional state.</p>
      </abstract>
      <kwd-group>
        <kwd>Personality</kwd>
        <kwd>Emotions</kwd>
        <kwd>Music</kwd>
      </kwd-group>
    </article-meta>
  </front>
  <body>
    <sec id="sec-1">
      <title>-</title>
      <p>
        We experience emotions in every facet of our life (e.g., during decision making,
thinking, creativity), and our behavior is in uenced by the emotional state we
are in [
        <xref ref-type="bibr" rid="ref16">16</xref>
        ]. To regulate our emotional states, we rely on 162 di erent methods
where listening to music is the second most used method [
        <xref ref-type="bibr" rid="ref9">9</xref>
        ].
      </p>
      <p>
        Within an emotion regulation method, we can adopt di erent strategies,
such as, changing, enhancing, or maintaining our emotional states. Previous
research has found that the preferred strategy is based on individual di erences
(e.g., [
        <xref ref-type="bibr" rid="ref11">11</xref>
        ]). For example, some people prefer to be cheered up when feeling sad,
while others would like to stay in this emotional state a bit longer. Research has
shown that composers are able to e ectively express the intended emotion of
their song to their audience [
        <xref ref-type="bibr" rid="ref13">13</xref>
        ], and that music is able to induce bona de
emotions [
        <xref ref-type="bibr" rid="ref16">16</xref>
        ]. The ability of music to express and induce di erent kind of emotions
makes it well suited to support emotion regulation.
      </p>
      <p>Current music applications that feature the ability for users to listen to music
that ts their emotional state, assume that they want to listen to music in line
with how they feel. However, since people adopt di erent emotion regulation
strategies, they may not always desire music which is similar with their emotional
state. Hence, in order to recommend the most appropriate music for users and
their current emotional state, understanding music listening needs on a general
as well as on an individual level is needed.</p>
      <p>With this work we seek to expand the understanding of how one's
emotional state relates to the preferred (emotionally laden) music. Music is known
to regulate emotions, but it is not known how emotional states relate to di
erent types of emotionally laden music preferences, nor how preference di erences
breakdown on an individual level by looking at personality traits.</p>
      <p>This leads us to the following research questions:
1. How do emotional states relate to emotionally laden music preferences?
2. How do personality traits relate to emotionally laden music preferences?</p>
      <p>An online user study was conducted where participants were asked to rate
di erent emotionally laden music pieces on the listening likelihood based on their
current emotional state. Among 359 participants we found that the emotional
state is related to the use of emotionally laden music. Furthermore, individual
di erences were identi ed based on personality traits.</p>
      <p>We continue with the related work, method, ndings, and discussion.
2</p>
    </sec>
    <sec id="sec-2">
      <title>Related work</title>
      <p>
        Ample research has investigated the e ects of music and the importance of it in
everyday life. For example, Thompson and Robitaille found that composers are
e ective in transferring the intended emotion of the music pieces to their
audience [
        <xref ref-type="bibr" rid="ref13">13</xref>
        ], indicating that people perform well at interpreting music emotions.
People are not only good at recognizing emotions in music, but music is also
able to induce emotions in such a way that it is used as experimental stimuli
(e.g., [
        <xref ref-type="bibr" rid="ref16">16</xref>
        ]). Others have investigated how people use music. Parkinson and
Totterdell surveyed a ect-regulation strategies, and found that music is used as a
common means [
        <xref ref-type="bibr" rid="ref9">9</xref>
        ]. Although the e ects and usages of music has been extensively
investigated, it is striking that to our knowledge, no research has focused on how
emotionally laden music is used to regulate which emotion and how di erences
exist on an individual level. With this work we try to answer these questions.
3
      </p>
    </sec>
    <sec id="sec-3">
      <title>Method</title>
      <p>Procedure. We developed an online experiment to get insights into the
relationship between emotional states and emotionally laden music (Figure 1). In
this experiment, participants were put in an emotional state and were asked to
rate di erent emotionally laden music pieces on the listening likelihood, based on
their emotional state. Participants were recruited (N =382) through Amazon
Mechanical Turk. Participation was restricted to those located in the United States,
and with a very good reputation. Several comprehension-testing questions were</p>
      <p>A) Inducing an
Emotionally emotional state</p>
      <p>laden
film clips
Film
clip</p>
      <p>Emotional
state check</p>
      <p>Emotionally
laden
music
5 different
music pieces</p>
      <p>B) Rating of emotionally
laden music pieces</p>
      <p>C) Concluding
questionnaires
Annotating
music pieces</p>
      <p>Likelihood
questions</p>
      <p>BFI &amp; demo.</p>
      <p>Questionnaires
used to lter out fake and careless entries. This left us with 359 completed and
valid responses. Gender (174 men and 185 women) and age (range 19-68, median
31) information indicated an adequate distribution.</p>
      <p>
        Participants were informed that an emotional state is going to be induced
and were given a consent form. The study started with an example to
familiarize participants with the study. To induce an emotion, we used the lm clips
presented in Table 1. The lm clip of Hannah and her Sisters was always shown
in the example to provide a constant (neutral) baseline stimulus [
        <xref ref-type="bibr" rid="ref5">5</xref>
        ]. For the
actual study, we randomly assigned the remaining lm clips. A short synopsis was
provided before playback to increase involvement, and improve understanding
of the lm clips' content [
        <xref ref-type="bibr" rid="ref15">15</xref>
        ]. In line with the procedure of Hewig et al., we
asked participants at the end of the lm clip to indicate how they were feeling
(by selecting an emotion from the set as seen in Table 1), and not what they
thought the lm clip was suppose to express [
        <xref ref-type="bibr" rid="ref7">7</xref>
        ]. In the next step, ve emotionally
laden music pieces, from within and between the emotion categories (Table 2),
were randomly presented. Participants were asked to annotate the emotion they
thought the music piece was trying to express (by selecting an emotion from the
set as seen in Table 2), and the likelihood (5-point Likert scale; never-always) of
listening to such emotionally laden music, considering their (reported) emotional
state. The study ended with the personality questionnaire and demographics.
Materials. For our stimuli we relied on existing materials that have been tested
in prior studies. To induce an emotional state, we used lm clips as they are the
most powerful emotion elicitation technique in a controlled environment [
        <xref ref-type="bibr" rid="ref10">10</xref>
        ].
Hewig et al. designed lm clips to induce an emotional state without sound, and
categorized them based on Ekman's emotion categorization (anger, fear, happy,
surprise, disgust, and sad; Table 1) [
        <xref ref-type="bibr" rid="ref7">7</xref>
        ]. Using muted stimuli allowed us to control
for con icts with our music pieces in the annotation step of the study. 1
      </p>
      <p>
        We used the emotionally laden music pieces created by Eerola and Vuoskoski.
They de ned music pieces based on the emotional value they bear, based on
Ekman's emotion categorization. Film soundtracks were used as they are created
with the purpose to mediate powerful emotional cues. Additionally, as they are
1 As the surprise emotion only lasts seconds [
        <xref ref-type="bibr" rid="ref2">2</xref>
        ], we decided not to include this.
instrumental, they are relatively neutral in terms of musical preferences and
(artist) familiarity (Table 2) [
        <xref ref-type="bibr" rid="ref1">1</xref>
        ]. 2
      </p>
      <p>
        We assessed personality traits with the widely used 44-item Big Five
Inventory (BFI; 5-point Likert scale; disagree strongly - agree strongly [
        <xref ref-type="bibr" rid="ref8">8</xref>
        ]), which
describes personality in terms of openness to experience, conscientiousness,
extraversion, agreeableness, and neuroticism.
4
      </p>
    </sec>
    <sec id="sec-4">
      <title>Findings</title>
      <p>The analyses were done based on participants' reported emotional state after
the lm clip was shown, not on the intended induced emotion by the lm clip.
The distribution of the reported emotional states were as follows: happy (n=55),
neutral (n=82), anger (n=62), disgust (n=56), fear (n=79), and sad (n=61).</p>
      <p>An initial one-way multivariate analysis of variance (MANOVA) was
conducted to test the relationship between emotionally laden music pieces and
emotional states. A signi cant MANOVA e ect was obtained (Wilks' Lambda =
.523, F (25; 1164:24) = 8.89, p &lt;.001) with a moderate e ect size ( 2=.13). The
homogeneity of variance assumption was tested for all the emotionally laden
music pieces. Levene's F test showed that the music pieces depicting the emotional
states happy and tender do not meet the requirement of p &gt;.05. None of the
largest standard deviations of the two pieces were more than four times the size
of the corresponding smallest, suggesting that follow-up ANOVAs are robust.</p>
      <p>
        Post-hoc tests (Tukey HSD) were performed to examine individual mean
di erence comparisons across the six emotional states and the ve emotionally
laden music pieces. The results reported here were compared against a neutral
emotional state and were all statistically signi cant (p &lt;.05). Results revealed
that in general, participants preferred happy and tender music when in a neutral
emotional state. However, in a angry or disgusted state, participants preferred
2 Eerola and Vuoskoski [
        <xref ref-type="bibr" rid="ref1">1</xref>
        ] replaced disgust with tender, as disgust is rarely expressed
by music. Music depicting surprise was omitted due to lack of statistical signi cance.
angry or fearful music. They also preferred sad music when they were feeling
sad. Additionally, participants indicated a dislike of happy and tender music
when they felt angry, fearful, or disgusted.
      </p>
      <p>Follow-up ANOVAs were conducted to test for individual di erences. Results
revealed that in a neutral emotional state, participants who scored high on
agreeableness tend to listen more to happy (F (1; 19:27) =16.12, p &lt;.001) and tender
(F (1; 11:89) =11.40, p &lt;.005) music. When participants felt happy, the ones who
scored high on openness tend to listen more to happy music (F (1; 9:02) =8.85,
p &lt;.05). Participants who scored high on neuroticism and felt disgusted tend to
listen more to sad music (F (1; 12:73) =8.47, p &lt;.005). Lastly when participants
felt sad, and scored high on extraversion (F (1; 16:95) =9.96, p &lt;.005),
agreeableness (F (1; 13:29) =7.81, p &lt;.05), or openness (F (1; 16:29) =9.57, p &lt;.005),
they tend to listen more to happy music.
5</p>
    </sec>
    <sec id="sec-5">
      <title>Discussion</title>
      <p>Our data show that the emotional state in uences the (emotionally laden)
music people listen to. In a neutral emotional state, happy and tender music is
consumed more frequently. Additionally, ndings indicate that people in general
prefer emotionally laden music that is in line with their emotional state. Angry
and fearful music is preferred when feeling angry or disgusted, whereas preference
for happy and tender music decreases for these emotional states. Additionally,
we found an increase of sad music in a sad state.</p>
      <p>Taking personality traits into account, individual di erences emerged. One of
our ndings showed that those who scored high on openness, extraversion, and
agreeableness are more inclined to listen to happy music when they are feeling
sad. In other words; they are trying to cheer themselves up with happy music.
On the other hand, we found that those who are neurotic try to maintain their
negative emotional state by listening to more sad songs.</p>
      <p>
        In order to provide personalized music recommendations, we identi ed
important individual di erences that deviate from the notion that users desire to
listen to music which is in line with their emotional state. By using personality to
identify individual di erences, we join the emergent interest of personality-based
personalized systems. Several solutions have already been proposed to
incorporate personality (e.g., [
        <xref ref-type="bibr" rid="ref14 ref3 ref4">3, 4, 14</xref>
        ]). For example, adaptation of the user interface
of music recommender systems based on personality traits [
        <xref ref-type="bibr" rid="ref4">4</xref>
        ]. Also the
extraction of emotion from social media is starting to establish (e.g., Twitter feeds [
        <xref ref-type="bibr" rid="ref6">6</xref>
        ]).
Given our results there are several implications to consider. Music systems could
anticipate the next song in the queue, or provide a list of recommendations, based
on the user's current emotional state. This allows the system to better serve the
user's music listening needs, and support their emotion regulation strategy.
      </p>
      <p>
        Although we relied on self-report measures to assess emotions (emotion
induction as well as music annotations) through an online platform, over 85% of
the responses were in line with the original classi cations that have been
extensively tested priorly [
        <xref ref-type="bibr" rid="ref1 ref7">1, 7</xref>
        ]. This suggests that the used methods were e ective.
      </p>
      <p>Ferwerda et al.</p>
      <p>
        Our results focused on individual di erences of music preferences based on
general emotional states. However, as Tamir and Ford [
        <xref ref-type="bibr" rid="ref12">12</xref>
        ] noted, emotion
regulation strategies depend not only on individual di erences, but also on the context
that people are situated in. They found that people want to experience
unpleasant emotions to attain certain instrumental bene ts. That is, people want to
feel bad when they expect it to give them bene ts. For example, in confronting
situations. We will address the in uence of context in future work.
6
      </p>
    </sec>
    <sec id="sec-6">
      <title>Acknowledgments</title>
      <p>This research is supported by the Austrian Science Fund: P25655, and the EU
FP7/2013-2016 through the PHENICX project under grant agreement 601166.</p>
    </sec>
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