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  <front>
    <journal-meta />
    <article-meta>
      <title-group>
        <article-title>It Takes Two, Baby: Style and Tangibles for Recommending and Interacting with Videos</article-title>
      </title-group>
      <contrib-group>
        <contrib contrib-type="author">
          <string-name>Mehdi Elahi</string-name>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Rosella Gennari</string-name>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Alessandra Melonio</string-name>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Francesco Ricci</string-name>
          <email>fricci@unibz.it</email>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <aff id="aff0">
          <label>0</label>
          <institution>Computer Science Faculty, Free University of Bozen-Bolzano</institution>
          ,
          <addr-line>Bolzano 39100</addr-line>
          ,
          <country country="IT">Italy</country>
        </aff>
      </contrib-group>
      <pub-date>
        <year>2018</year>
      </pub-date>
      <fpage>28</fpage>
      <lpage>30</lpage>
      <abstract>
        <p>Children, nowadays, are great consumers of media for them [6], and there is growing interest towards novel mechanisms that can consider their speci c needs and improve both the recommendation process and output of videos for them. Children, in fact, have unique characteristics, which change with age. In particular, in the 8{12 age range, they like challenging interactions with systems, they enjoy exploring and \to feel the experts". The majority of current recommendation solutions are unable to leverage on such speci c features of children, and others, when interacting with them and recommending adequate videos. In this paper, we introduce ITTuB, an exploratory project, set at the intersection of recommender system and interaction design for children. Starting from previous research in the two areas, it plans to introduce tangibles for enhancing the interaction of children with videos, and to leverage stylistic features of videos in order to deliver recommendations that are optimized for children. This workshop paper presents the main ideas of ITTuB.</p>
      </abstract>
    </article-meta>
  </front>
  <body>
    <sec id="sec-1">
      <title>-</title>
      <p>
        The majority of existing movie-sharing applications tend to combine
collaborative ltering techniques with semantic features, such as the video genre, director,
cast, or tags and textual reviews, for recommending videos [
        <xref ref-type="bibr" rid="ref12">12</xref>
        ]. We conjecture
that such solutions are not su cient for generating video recommendations for
children. Visual stylistic features are not taken into account in the
recommendation process of videos. However, stylistic features of videos are perceivable for
children and hence they can have a huge impact on the formation of children's
preferences for videos. We sustain that video recommender systems meant for
children should consider such information so as to deliver a quality video
recommendation experience to children.
      </p>
      <p>
        More in general, careful considerations of children's characteristics is
necessary for designing recommender systems that can e ectively interact with
children. Moreover, children are not a homogeneous group, e.g., their characteristics
change with age. While children become adults, they go through a number of
stages, which include unique cognitive, emotional, social and physical challenges,
that developers of interactive recommender systems for children must take into
consideration in order to make truly engaging systems for children. In
particular, tweens, in the age range 8{12, have their own speci c characteristics. For
example, richer interactions are preferred by tweens than by younger children,
but a large number of choices, which could be adequate to adults, still confuses
tweens and a ects the perceivability of the interactions; at the same time, play
is still a fundamental component of the design of interactions for tweens [
        <xref ref-type="bibr" rid="ref11">11</xref>
        ].
      </p>
      <p>
        ITTuB is a project that, by carefully analysing the characteristics of tweens,
seeks to investigate how to design an interactive recommender system of videos
for them. The research around ITTuB is novel from two convergent viewpoints.
The design of the interaction of the system with tweens will itself be novel
because it will explore innovative interaction modalities based on playful tangible
objects (brie y, tangibles) for tweens. Fig. 1 shows an example of a playful
tangible progression board for 8{10 year tweens, using di erent micro-electronics
components for interacting with children [
        <xref ref-type="bibr" rid="ref9">9</xref>
        ]. The recommendation process
design will also be novel because it will investigate and use adequate stylistics
features of videos for tweens. The result is a new line of interdisciplinary research
investigations that have so far received almost no attention from the community
[
        <xref ref-type="bibr" rid="ref4">4</xref>
        ].
      </p>
      <p>The paper is organised as follows. It starts with related work and background
in the two areas converging into ITTuB: recommender system design and
interaction design and children. The paper then moves on explaining the main ideas
of ITTuB. It does so by giving the main context scenarios of the project and its
research goals.
2</p>
    </sec>
    <sec id="sec-2">
      <title>Background and Related Work</title>
      <p>
        Traditional video recommender systems rely mainly on the assumption that
users' preferences may related to the semantic features of videos (e.g. [
        <xref ref-type="bibr" rid="ref15 ref8">15, 8</xref>
        ],
plot, genre, director, and actors) and, to a less extent, by the stylistic
properties of videos [
        <xref ref-type="bibr" rid="ref2 ref5">2, 5</xref>
        ] (e.g., color, motion, lighting key). Recommendations are
automatically computed using implicit or explicit preferences of users on those
attributes [
        <xref ref-type="bibr" rid="ref8">8</xref>
        ]. However, recent work on recommender systems suggested that,
when choosing a product, users' choices may be in uenced more by the stylistic
visual aspect of items and less by their semantic or syntactic properties [
        <xref ref-type="bibr" rid="ref10 ref14 ref3 ref5">3, 10,
14, 5</xref>
        ].
      </p>
      <p>In ITTuB, we make a di erent assumption. We still believe that traditional
video attributes are important to be used in information retrieval applications,
where the goal is to provide a way of indexing multimedia content so that users
can explicitly (i.e., manually) query that content at the semantic level. However,
we wish to investigate if this assumption holds also for recommender systems
which aim at automatically nding contents that the user prefers, without the
user querying the system.</p>
      <p>
        Therefore, our goal is to leverage the stylistic features automatically extracted
from video content and complement them with the semantic features so as to
deliver video recommendations. For this purpose, we explore and evaluate a
recent approach for movie recommendations that integrates traditional semantic
attributes, such as genre, director and cast, with stylistic features, such as
lighting, colors, background, and movements. Such aesthetic features are likley to
matter for recommending videos to tweens, who are 8{12 year olds with speci c
characteristics [
        <xref ref-type="bibr" rid="ref11">11</xref>
        ]; according to recent research ndings for muldimedia stories,
aesthetic features of multimedias a ect tweens' recommendations highly, more
than other syntactic features such as titles [
        <xref ref-type="bibr" rid="ref13">13</xref>
        ].
      </p>
      <p>
        More in general, tweens tend to enjoy systems which are highly interactive.
They are growing up expecting things to give them immediate feedback about
their choices; compared to other generations, they are more skilled about
technologies, and have di ering abilities to express their ideas and to follow
structured tasks [
        <xref ref-type="bibr" rid="ref11">11</xref>
        ]. In ITTuB, the focus is on tweens, who are believed to belong
to the concrete operational stage, when intelligence starts to be logical but still
refers to concrete things. Another reference child development theory for ITTuB
is constructivism (e.g., [
        <xref ref-type="bibr" rid="ref7">7</xref>
        ]). According to this, a child should be given tangible
physical objects and tools to construct knowledge, thereby activating di erent
senses. Several studies have shown the e ectiveness of tangible interaction
models when adopted in recommender systems. For instance, it has been shown that
users' engagement is signi cantly improved when tangible interaction has been
employed through the materiality dimension of objects, e.g., [
        <xref ref-type="bibr" rid="ref1">1</xref>
        ]. In spite of such
promising studies, the full application of tangible interaction in video
recommendations for tweens, with novel forms of recommendations, has not been yet
very explored and needs further investigation, as considered in ITTuB.
3
      </p>
    </sec>
    <sec id="sec-3">
      <title>Scenarios and Research Goals</title>
      <p>Hereby, we give preliminary scenarios concerning the intended usage of the
ITTuB recommender system, and the research goals of ITTuB presented below.</p>
      <p>SCENARIO 1: Amirali wants quality video recommendations.
Amirali is a 12-year old boy, who often uses his IPad tablet for accessing videos
over the Internet and posting his game play sessions. However, the recommended
videos do not often satisfy his expectations. \If I watch a cartoon, it does not
mean that I only want to watch cartoons all my life!"|thinks Amirali. Yet, that
is what happens when he uses video recommender applications on his IPad.
SCENARIO 2: Lucrezia rates her preferred videos.</p>
      <p>Lucrezia is an 8-year old child, addicted to musical movies; she is utterly in love
with Frozen! She watches them online, but all existing recommender systems
annoy her with their continuous boring questions. One day, Emily, her literature
teacher, shows her the ITTuB app and the tangible toolkit of ITTuB. She is
reasonable, but cautious, about how her pupils uses apps, and has done a great
job of educating them about the people they might encounter online. Emily has
chosen the ITTuB app because it guarantees ethical treatment of users data.
Lucrezia opens it because she is attracted by the tangible toolkit that comes
with the app. The app challenges Lucrezia to play with her preferred videos so
as to give her better recommendations. The girl is immediately engaged and
gives the app info on her preferred videos by using tangibles of the toolkit. The
app recommender system learns about her choices and uses them to ne tune
its recommendation mechanism.</p>
      <p>The main goals of the research are related to the scenarios. The most
ambitious goal is to nurture children's knowledge of features of videos, recommended
to them (e.g., colour, light, and motion). Thus, the system should be meant as
an educational tool, which encourages children to re ect about what they watch.
While the children may not be interested in understanding techniques, certain
explanations with regard to the emotional aspects of the videos formulated by
visual features, can be bene cial.</p>
      <p>
        The other main goal is to investigate novel interaction approaches for
children's video recommendations, which can foster children's curiosity to explore
videos and their features. Being targeted primarily to younger children, the
system should be playful, e.g., gami ed, and mix tangible physical objects and
traditional screen-based interfaces for videos, like in [
        <xref ref-type="bibr" rid="ref9">9</xref>
        ]. Towards the end, ITTuB
will strive to investigate whether its results can cater for di erent populations,
who may bene t from them.
4
      </p>
    </sec>
    <sec id="sec-4">
      <title>Conclusions</title>
      <p>The paper presents the ITTuB project, which explores how to design an
interactive recommender system for tweens. It presents the background and related
work on which ITTuB is based. In particular, the paper explains tweens' main
characteristics and why they matter for the design of the ITTuB system. Then
the paper advances ideas for the design of the system: they aim to combine a
novel recommendation mechanism, which exploits sytlistic features of videos,
with novel interaction modalities, which mix the virtual worlds of videos and
the physical world of tangible objects for tweens.</p>
    </sec>
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