<!DOCTYPE article PUBLIC "-//NLM//DTD JATS (Z39.96) Journal Archiving and Interchange DTD v1.0 20120330//EN" "JATS-archivearticle1.dtd">
<article xmlns:xlink="http://www.w3.org/1999/xlink">
  <front>
    <journal-meta>
      <journal-title-group>
        <journal-title>Sideways</journal-title>
      </journal-title-group>
    </journal-meta>
    <article-meta>
      <title-group>
        <article-title>Event-driven TV Programs Web Community Exploration</article-title>
      </title-group>
      <contrib-group>
        <contrib contrib-type="author">
          <string-name>Ruggero G. Pensa</string-name>
          <email>pensa@di.unito.it</email>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Claudio Schifanella</string-name>
          <email>schi@di.unito.it</email>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Luca Vignaroli</string-name>
          <email>luca.vignaroli@rai.it</email>
          <xref ref-type="aff" rid="aff1">1</xref>
        </contrib>
        <aff id="aff0">
          <label>0</label>
          <institution>Department of Computer Science, University of Turin</institution>
          ,
          <addr-line>Corso Svizzera 185, Turin</addr-line>
          ,
          <country country="IT">Italy 10149</country>
        </aff>
        <aff id="aff1">
          <label>1</label>
          <institution>RAI CRIT - Turin</institution>
          ,
          <addr-line>Via Cavalli 6, Turin</addr-line>
          ,
          <country country="IT">Italy 10149</country>
        </aff>
      </contrib-group>
      <pub-date>
        <year>2017</year>
      </pub-date>
      <volume>4</volume>
      <abstract>
        <p>With the goal of understanding how major public interest events are perceived by the TV public and how the users' interests evolve in time, we introduce a data collection, integration and analysis framework that allows to compute, characterize and explore dynamic social web communities. We focus on communities of Twitter users that interact each-other around specific T V events and track their public cybersocial activities to analyze and visualize the information difusion processes and understand how they afect the community structure of the social network.</p>
      </abstract>
    </article-meta>
  </front>
  <body>
    <sec id="sec-1">
      <title>INTRODUCTION</title>
      <p>People on the Web talk about television. Trending topics and
concepts arise from TV users’ “cybersocial” activities thus influencing
the community structure of the social network. Users aggregate
themselves around topics and concepts that emerge from major
events. The U.S. presidential primaries have a clear effect on the
community structure of users around the world, but such groups
are subject to changes as the candidates pronounce some speech in
favor or against some policies (e.g., on immigration, protectionism,
welfare) that concern them, directly or indirectly. Capturing and
understanding the evolution of such communities promptly is of
great value for a number of stockholders: advertisers, broadcast
programmers, market and society analysts.</p>
      <p>
        Within the RAI research project on the study of the integration
between social networks and the TV world, the collaboration with
the University of Turin led in the last years to the design and
development of a general framework1 for the collection and analysis of
heterogeneous data coming from standard TV sources (EPGs,
editorial metadata, audience metrics) and social networks conversations
[
        <xref ref-type="bibr" rid="ref1">1</xref>
        ]. Within our general purpose social data collection, integration
and analysis framework [
        <xref ref-type="bibr" rid="ref9">9</xref>
        ], in this paper, with the goal of
understanding how major public interest events are perceived by the TV
public and how the users’ interests evolve in time, we present a
new application that allows to compute, characterize and explore
dynamics social web communities.
      </p>
      <p>
        Our application enables both guided and automatic extraction
of emergent topics and concepts from Twitter public conversations.
Based on such concepts, it builds the social network of users by
leveraging their interactions. Two users are considered as
interacting each other if they mention each-other explicitly (in a retweet or
a reply) or whenever they refer to similar concepts in their
conversations. Moreover, our application enables the execution of multiple
community detection algorithms [
        <xref ref-type="bibr" rid="ref2 ref3 ref4">2–4</xref>
        ] to uncover the underlying
community structure of the network at diferent time points. Those
communities are then described in terms of social influence of their
nodes using several metrics (pagerank, betweenness and
eigenvector centrality) [
        <xref ref-type="bibr" rid="ref7">7</xref>
        ]) as well as in terms of topics and concepts
characterizing their interactions (by using summarization). [
        <xref ref-type="bibr" rid="ref8">8</xref>
        ]).
Finally, the application enables the observation, analysis and
characterization of the difusion of topics and concepts in the overall
network and among the diferent communities [
        <xref ref-type="bibr" rid="ref10">10</xref>
        ]. It could then
support the activity of researchers, analysts and practitioners
interested in social media analysis and network dynamics. Our use case
relies on real public data gathered from Twitter, related to one of
the most important TV event broadcasted by RAI.
2
      </p>
    </sec>
    <sec id="sec-2">
      <title>RELATED WORK</title>
      <p>
        In the last three years, a number of tools have been proposed to
address the problem of complexity and dynamicity in network
analysis and visualization (eg., [
        <xref ref-type="bibr" rid="ref11 ref13 ref6">6, 11, 13</xref>
        ]). GalaxyExplorer [
        <xref ref-type="bibr" rid="ref6">6</xref>
        ] is an
influence-driven visual analysis system for exploring how users
influence each other in a social network. The authors use a
galaxybased visual metaphor to simplify the visual complexity of large
graphs. In [
        <xref ref-type="bibr" rid="ref12">12</xref>
        ], the authors propose a spatial visualization system
to detect geo-social event from Twitter conversations. Gazouille [
        <xref ref-type="bibr" rid="ref5">5</xref>
        ]
is another location-based system for discovering local events in
geolocalized social media streams. Insight4News [
        <xref ref-type="bibr" rid="ref11">11</xref>
        ], instead, connects
news articles to social conversations, by using topic detection and
tweet summarization, and performs hashtag recommendation.
Finally, in [
        <xref ref-type="bibr" rid="ref13">13</xref>
        ] the authors adopts semi-supervised machine learning
to perform community detection via a label propagation approach
that leverages an epidemic spreading model. Diferently from them,
the focus of our work is the community. Our framework, in fact,
aims at detecting and characterizing the evolution of the
communities gravitating around TV events. Furthermore, we analyze and
visualize the information difusion dynamics at both the single node
level and the community level.
3
      </p>
    </sec>
    <sec id="sec-3">
      <title>MESOONTV SYSTEM OVERVIEW</title>
      <p>Our framework consists of three internal layers, covering all the
phases from data collection, representation and integration to data
analysis, and a visualization layer (see Figure 1). More specifically,
a Source processing layer contains the diferent modules for
collecting all the data from web sources to be conveyed in the social
graph and other data representation technologies. It accesses a
number of predefined web/social/media sources (Twitter, oficial
web sites, TV channels, ontological information sources) and
continuously processes the information collected in real-time to detect
the named entities (people, places and events) trough the use of a
Named-Entity Recognition module and a topic extraction module.
The collected users, topics, concepts and relationships among them
are then stored in the social graph layer based on Neo4j2 and
MySQL3, which contains all the modules needed to store and
manage the social graph. The social query and analysis layer ofers
functionalities for querying, browsing and analyzing the graph.
More specifically the analysis module provides a set of community
detection and social network analysis components.</p>
      <p>
        Community detection if performed by adopting two well-known
algorithms: Louvain [
        <xref ref-type="bibr" rid="ref2">2</xref>
        ] and DEMON [
        <xref ref-type="bibr" rid="ref3">3</xref>
        ]. Louvain is a greedy
optimization method that attempts to optimize the “modularity” of
a partition of the network. Modularity measures the density of
links inside communities compared to links between communities
[
        <xref ref-type="bibr" rid="ref2">2</xref>
        ]. DEMON, instead, is an algorithm that detect hierarchical and
overlapping communities in networks. It enables the discovery of
global communities from multiple ego-minus-ego networks thanks
2http://www.neo4j.com
3http://www.mysql.com
to a label propagation algorithm. A ego-minus-ego network is
deifned as the ego-network of a node v without the node v itself [
        <xref ref-type="bibr" rid="ref3">3</xref>
        ].
The analysis module implementing Louvain and the metrics that
measure user influence is based on Gephi 4, while, for DEMON, we
use our own adaptation of the authors’ Java implementation.
      </p>
      <p>The visualization layer is constituted of the web application, that
adopt modern web technologies to enable responsiveness and
highlevel interaction patterns: node.js as web page server, a REST API
for database querying, D3.js as graph visualization and browsing
library. To cope with the potential huge amount of data, we adopt
a caching mechanism on the layout, nodes, links and communities.
4</p>
    </sec>
    <sec id="sec-4">
      <title>DEMONSTRATION SCENARIO</title>
      <p>In our use case scenario, we gathered Twitter data from February
9th to 13th 2016. The data are related to the five episodes of the 2016
edition of the Sanremo Music Festival, the most popular Italian song
contest and awards. Overall, more than 2.52M tweets of 176, 760
users have been processed. In these conversations, the relevant
concepts are mentioned more than 1.80M times, while the overall
number of hashtags is 3.60M. Our goal is to recognize and
characterize those communities that gravitates around some specific
events that happened during this major national event. In
particular, during the 2016 edition, apart from the song contest itself,
several events attracted the public interest and were extensively
discussed in newspapers, news broadcasting, blogs and social
media. For instance, in all episodes, some artists and guests promoted
the upcoming law on civil rights for the LGBT community. During
the second episode, there was a touching exhibition by Ezio Bosso,
an Italian composer known worldwide afected by an autoimmune
neurological disorder. In the final episode, Elio e le Storie Tese, a
well-known comedy rock band, performed their song dressed as
Kiss, the famous metal band; this exhibition was appreciated by Kiss
frontman Gene Simmons, thus gaining visibility at international
level</p>
      <p>A user has the possibility of selecting a set of concepts of interest
(e.g., the artists exhibiting during the event, “LGBT”, “Ezio Bosso”,
“Kiss”) or a set of “trending/emerging concepts” according to some
basic statistics. Then, a community detection algorithm is executed
on the Twitter interaction network of the users that mentioned
at least one of the selected concepts in their conversations (also
including replies and retweets). The network and their communities
are visualized as shown in Figure 2. Each community can be then
inspected individually and the application returns some related
statistics: the list of most influential users (according to pagerank,
betweenness centrality or other network metrics) the list of the
most relevant concepts and hashtags (identified by a summarization
technique) including both selected concepts and other co-occurrent
concepts. In Fig. 2, for instance, Community 2 is characterized by
the fact that the involved users talk about Dear Jack (an Italian rock
band), while the hashtag #MezzoRespiro refers to the title of the
song presented during the contest. Community 5, instead, is a broad
interest community dealing with Ezio Bosso and the civil rights of
LGBT people (#SanremoArcobaleno).</p>
      <p>The application supports also the analysis of the traces of the
information difusion processes involving individual users and
communities (see Figure 3). By retracing the timeline of each episode,
the application allows the user to visualize and compare the spread
of a number of selected concepts in the interaction network.
During each time interval, Twitter users that tweet, retweet or reply
in conversations mentioning a specific concept c are “turned on”
and highlighted with the color identifying c. In this visualization
modality, the information difusion process can be compared with
the overall Twitter activity represented by the curve on bottom of
Figure 3. This facility supports the discovery of difusion patterns,
as well as the visual comparison of difusion trends. Notice that
basic complex network statistics (number of nodes/edges, number of
connected components, clustering coeficient) are always available
on screen. Moreover, the user can observe the time evolution of
such metrics referring only to the highlighted subgraph. Though
usable on mobile devices, the application is optimized for 4K UHD
displays.</p>
      <p>Through the described platform, it is possible to identify and
visualize phenomena that occur on social networks with reference
to the television world such as emerging phenomena, their temporal
evolution and the relationships between the entities involved. The
conceptual navigation network allows the user to walk through
the concepts and involved social users mentioned within television
events in a particular timeline based on mentions of mentions
during television events.</p>
      <p>The flow of data coming from social networks is now seen as
a true additional information channel for the end user, for some
television programs it is a fruition line for some verse independent
of the television program it is generated. The platform described,
in addition to being used as a support to marketing choices, can
be used as a data source to tell television events from the point of
view of users who have lived and commented on them, creating
an unseen story that sees as protagonists the viewers themselves
with their perception and emotions tried during the viewing of a
television program. In fact, Digital Storytelling, or Narrative made
with digital instruments, consists of organizing selected content
from the web in a coherent system based on a narrative structure,
in order to obtain a tale composed of multiple elements of various
formats (video, audio, images, texts, maps, etc.). Digital Storytelling
is therefore a form of narrative particularly suitable for
communicative forms such as journalism, politics, marketing, autobiography,
didactics and it could became a new frontiers of the television world
to provide information and entertainment experiences that can be
visualized through diferent tools of fruition in synergy with each
other.
5</p>
    </sec>
    <sec id="sec-5">
      <title>CONCLUSIONS</title>
      <p>In this paper we presented an application that allows to find,
characterize and explore community of users in social networks
conversations. We demonstrate the efectiveness of the approach by
exploiting a use case in the TV setting related to a well known
Italian song festival. The collaboration between University of Turin
and RAI, the Italian broadcaster, is constantly evolving: in the next
months, we will integrate other sources that we are already
monitoring (e.g., Facebook), as well as new features for a more in-depth
characterization and comparison of users and communities.</p>
    </sec>
  </body>
  <back>
    <ref-list>
      <ref id="ref1">
        <mixed-citation>
          [1]
          <string-name>
            <given-names>Alessio</given-names>
            <surname>Antonini</surname>
          </string-name>
          , Luca Vignaroli, Claudio Schifanella, Ruggero G. Pensa, and Maria Luisa Sapino.
          <year>2013</year>
          .
          <article-title>MeSoOnTV: a media and social-driven ontology-based TV knowledge management system</article-title>
          .
          <source>In Proc. of ACM HT '13</source>
          .
          <fpage>208</fpage>
          -
          <lpage>213</lpage>
          .
        </mixed-citation>
      </ref>
      <ref id="ref2">
        <mixed-citation>
          [2]
          <string-name>
            <surname>Vincent</surname>
            <given-names>D</given-names>
          </string-name>
          <string-name>
            <surname>Blondel</surname>
          </string-name>
          ,
          <string-name>
            <surname>Jean-Loup</surname>
            <given-names>Guillaume</given-names>
          </string-name>
          , Renaud Lambiotte, and
          <string-name>
            <given-names>Etienne</given-names>
            <surname>Lefebvre</surname>
          </string-name>
          .
          <year>2008</year>
          .
          <article-title>Fast unfolding of communities in large networks</article-title>
          .
          <source>J. Stat. Mech. Theor. Exp</source>
          .
          <year>2008</year>
          ,
          <volume>10</volume>
          (
          <year>2008</year>
          ),
          <fpage>P10008</fpage>
          .
        </mixed-citation>
      </ref>
      <ref id="ref3">
        <mixed-citation>
          [3]
          <string-name>
            <given-names>Michele</given-names>
            <surname>Coscia</surname>
          </string-name>
          , Giulio Rossetti, Fosca Giannotti, and
          <string-name>
            <given-names>Dino</given-names>
            <surname>Pedreschi</surname>
          </string-name>
          .
          <year>2014</year>
          .
          <article-title>Uncovering Hierarchical and Overlapping Communities with a Local-First Approach</article-title>
          .
          <source>TKDD 9</source>
          ,
          <issue>1</issue>
          (
          <year>2014</year>
          ),
          <volume>6</volume>
          :
          <fpage>1</fpage>
          -
          <lpage>6</lpage>
          :
          <fpage>27</fpage>
          .
        </mixed-citation>
      </ref>
      <ref id="ref4">
        <mixed-citation>
          [4]
          <string-name>
            <given-names>Santo</given-names>
            <surname>Fortunato</surname>
          </string-name>
          .
          <year>2010</year>
          .
          <article-title>Community detection in graphs</article-title>
          .
          <source>Physics Reports</source>
          <volume>486</volume>
          ,
          <issue>3âĂŞ5</issue>
          (
          <year>2010</year>
          ),
          <fpage>75</fpage>
          -
          <lpage>174</lpage>
          . https://doi.org/10.1016/j.physrep.
          <year>2009</year>
          .
          <volume>11</volume>
          .002
        </mixed-citation>
      </ref>
      <ref id="ref5">
        <mixed-citation>
          [5]
          <string-name>
            <given-names>Pierre</given-names>
            <surname>Houdyer</surname>
          </string-name>
          , Albrecht Zimmermann, Mehdi Kaytoue, Marc Plantevit, Joseph Mitchell, and
          <string-name>
            <given-names>Céline</given-names>
            <surname>Robardet</surname>
          </string-name>
          .
          <year>2015</year>
          .
          <article-title>Gazouille: Detecting and Illustrating Local Events from Geolocalized Social Media Streams</article-title>
          .
          <source>In Proceedings of ECML PKDD</source>
          <year>2015</year>
          , Part III.
          <fpage>276</fpage>
          -
          <lpage>280</lpage>
          .
        </mixed-citation>
      </ref>
      <ref id="ref6">
        <mixed-citation>
          [6]
          <string-name>
            <given-names>Xiaotong</given-names>
            <surname>Liu</surname>
          </string-name>
          , Srinivasan Parthasarathy,
          <string-name>
            <surname>Han-Wei</surname>
            <given-names>Shen</given-names>
          </string-name>
          ,
          <string-name>
            <given-names>and Yifan</given-names>
            <surname>Hu</surname>
          </string-name>
          .
          <year>2015</year>
          .
          <article-title>GalaxyExplorer: Influence-Driven Visual Exploration of Context-Specific Social Media Interactions</article-title>
          .
          <source>In Proceedings of WWW 2015 - Companion</source>
          Volume.
          <volume>215</volume>
          -
          <fpage>218</fpage>
          .
        </mixed-citation>
      </ref>
      <ref id="ref7">
        <mixed-citation>
          [7]
          <string-name>
            <given-names>Mark E. J.</given-names>
            <surname>Newman</surname>
          </string-name>
          .
          <year>2010</year>
          .
          <article-title>Networks: An Introduction</article-title>
          . Oxford University Press, New York, NY, USA.
        </mixed-citation>
      </ref>
      <ref id="ref8">
        <mixed-citation>
          [8]
          <string-name>
            <surname>Brendan O'Connor</surname>
            ,
            <given-names>Michel</given-names>
          </string-name>
          <string-name>
            <surname>Krieger</surname>
            , and
            <given-names>David</given-names>
          </string-name>
          <string-name>
            <surname>Ahn</surname>
          </string-name>
          .
          <year>2010</year>
          .
          <article-title>TweetMotif: Exploratory Search and Topic Summarization for Twitter</article-title>
          .
          <source>In Proceedings of ICWSM</source>
          <year>2010</year>
          .
        </mixed-citation>
      </ref>
      <ref id="ref9">
        <mixed-citation>
          [9]
          <string-name>
            <given-names>R. G.</given-names>
            <surname>Pensa</surname>
          </string-name>
          ,
          <string-name>
            <given-names>M. L.</given-names>
            <surname>Sapino</surname>
          </string-name>
          ,
          <string-name>
            <given-names>C.</given-names>
            <surname>Schifanella</surname>
          </string-name>
          , and
          <string-name>
            <given-names>L.</given-names>
            <surname>Vignaroli</surname>
          </string-name>
          .
          <year>2016</year>
          .
          <article-title>Leveraging Cross-Domain Social Media Analytics to Understand TV Topics Popularity</article-title>
          .
          <source>IEEE Computational Intelligence Magazine</source>
          <volume>11</volume>
          ,
          <issue>3</issue>
          (Aug
          <year>2016</year>
          ),
          <fpage>10</fpage>
          -
          <lpage>21</lpage>
          . https://doi.org/10. 1109/
          <string-name>
            <surname>MCI</surname>
          </string-name>
          .
          <year>2016</year>
          .2572518
        </mixed-citation>
      </ref>
      <ref id="ref10">
        <mixed-citation>
          [10]
          <string-name>
            <surname>Daniel</surname>
            <given-names>M.</given-names>
          </string-name>
          <string-name>
            <surname>Romero</surname>
          </string-name>
          , Brendan Meeder, and
          <string-name>
            <surname>Jon</surname>
            <given-names>M.</given-names>
          </string-name>
          <string-name>
            <surname>Kleinberg</surname>
          </string-name>
          .
          <year>2011</year>
          .
          <article-title>Diferences in the mechanics of information difusion across topics: idioms, political hashtags, and complex contagion on twitter</article-title>
          .
          <source>In Proceedings of WWW</source>
          <year>2011</year>
          .
          <volume>695</volume>
          -
          <fpage>704</fpage>
          .
        </mixed-citation>
      </ref>
      <ref id="ref11">
        <mixed-citation>
          [11]
          <string-name>
            <surname>Bichen</surname>
            <given-names>Shi</given-names>
          </string-name>
          ,
          <string-name>
            <given-names>Georgiana</given-names>
            <surname>Ifrim</surname>
          </string-name>
          , and
          <string-name>
            <given-names>Neil</given-names>
            <surname>Hurley</surname>
          </string-name>
          .
          <year>2014</year>
          .
          <article-title>Insight4News: Connecting News to Relevant Social Conversations</article-title>
          .
          <source>In Proceedings of ECML PKDD</source>
          <year>2014</year>
          , Part III.
          <fpage>473</fpage>
          -
          <lpage>476</lpage>
          .
        </mixed-citation>
      </ref>
      <ref id="ref12">
        <mixed-citation>
          [12]
          <string-name>
            <surname>Shoko</surname>
            <given-names>Wakamiya</given-names>
          </string-name>
          , Adam Jatowt, Yukiko Kawai, and
          <string-name>
            <given-names>Toyokazu</given-names>
            <surname>Akiyama</surname>
          </string-name>
          .
          <year>2016</year>
          .
          <article-title>Analyzing Global and Pairwise Collective Spatial Attention for Geo-social Event Detection in Microblogs</article-title>
          .
          <source>In Proceedings of WWW</source>
          <year>2016</year>
          , Companion Volume.
          <volume>263</volume>
          -
          <fpage>266</fpage>
          .
        </mixed-citation>
      </ref>
      <ref id="ref13">
        <mixed-citation>
          [13]
          <string-name>
            <surname>Ying</surname>
            <given-names>Wen</given-names>
          </string-name>
          , Yuanhao Chen, and
          <string-name>
            <given-names>Xiaolong</given-names>
            <surname>Deng</surname>
          </string-name>
          .
          <year>2014</year>
          .
          <article-title>Epdemic spreading model based overlapping community detection</article-title>
          .
          <source>In Proceedings of ASONAM</source>
          <year>2014</year>
          .
          <volume>954</volume>
          -
          <fpage>959</fpage>
          .
        </mixed-citation>
      </ref>
    </ref-list>
  </back>
</article>