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  <front>
    <journal-meta />
    <article-meta>
      <title-group>
        <article-title>Analysing Media Coverage of political debates by automatically generated links to Radio &amp; Newspaper Items</article-title>
      </title-group>
      <contrib-group>
        <contrib contrib-type="author">
          <string-name>Martijn Kleppe</string-name>
          <email>kleppe@eshcc.eur.nl</email>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Laura Hollink</string-name>
          <email>l.hollink@vu.nl</email>
          <xref ref-type="aff" rid="aff3">3</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Max Kemman</string-name>
          <email>kemman@eshcc.eur.nl</email>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Damir Juric</string-name>
          <email>damir.juric@fer.hr</email>
          <xref ref-type="aff" rid="aff1">1</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Henri Beunders</string-name>
          <email>beunders@eshcc.eur.nl</email>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Jaap Blom</string-name>
          <email>jblom@beeldengeluid.nl</email>
          <xref ref-type="aff" rid="aff2">2</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Johan Oomen</string-name>
          <email>joomen@beeldengeluid.nl</email>
          <xref ref-type="aff" rid="aff2">2</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Geert-Jan Houben</string-name>
          <email>g.j.p.m.houben@tudelft.nl</email>
        </contrib>
        <aff id="aff0">
          <label>0</label>
          <institution>Erasmus Universiteit Rotterdam</institution>
        </aff>
        <aff id="aff1">
          <label>1</label>
          <institution>London Brunel University</institution>
        </aff>
        <aff id="aff2">
          <label>2</label>
          <institution>Nederlands Instituut voor Beeld en Geluid</institution>
        </aff>
        <aff id="aff3">
          <label>3</label>
          <institution>Vrije Universiteit Amsterdam</institution>
        </aff>
      </contrib-group>
      <abstract>
        <p>Students and researchers of media and communication sciences study the role of media in our society. They frequently search through media archives to manually select items that cover a certain event. When this is done for large time spans and across media-outlets, this task can however be challenging and laborious. Therefore, up until now the focus of researchers has been on manual and qualitative analyses of newspaper coverage. PoliMedia aims to stimulate and facilitate large-scale, cross-media analysis of the coverage of political events. We focus on the meetings of the Dutch parliament, and provide automatically generated links between the transcripts of those meetings, newspaper articles, including their original lay-out on the page, and radio bulletins. Via the portal at www.polimedia.nl researchers can search through the debates and find related media coverage in two mediaoutlets, facilitating a more efficient search process and qualitative analyses of the media coverage. Furthermore, the generated links are available via a SPARQL endpoint at data.polimedia.nl allowing quantitative analyses with complex, structured queries that are not covered by the search functionality of the portal, thus challenging the student to go across the academic borders and enter fields that previously have been neglected.</p>
      </abstract>
      <kwd-group>
        <kwd>eol&gt;Parliamentary debates</kwd>
        <kwd>linking</kwd>
        <kwd>mediatisation</kwd>
        <kwd>linked data</kwd>
        <kwd>media coverage</kwd>
        <kwd>newspapers</kwd>
        <kwd>radio</kwd>
      </kwd-group>
    </article-meta>
  </front>
  <body>
    <sec id="sec-1">
      <title>-</title>
      <p>An innovative approach of PoliMedia is that the coverage
in the media is incorporated in its original form (figure 4),
enabling analyses of both the mark-up of news articles as
well as the photos in newspapers allowing further
qualitative analyses of the media coverage. As a result, the
big advantage of the PoliMedia system is that it allows
students and researchers to make cross-media comparisons
in a straightforward way both quantitatively and
qualitatively. Earlier they had to manually search each
archive separately, using the archives proprietary metadata,
and decide whether or not a media item covers a certain
(political) event. The focus of the assignments in the
curriculum was therefore on qualitative analysis only.
Working with the PoliMedia portal gives students and
researchers a hands-on experience with a quantitative
approach to their field of study. In addition, it provides
them with substantive insights into how media coverage
varies over a large number of political events. We believe
that this type of insight is best learned through interaction
with the data, rather than, for example, literature study.
With the PoliMedia approach researchers can go to one
website where they will have access to all sources in a
standardized format. While students and researchers before
mainly used newspaper articles, the PoliMedia system
allows them now to make cross-media analyses in a more
efficient way. Furthermore, we made the automatically
generated links available through a SPARQL endpoint at
data.polimedia.nl, allowing quantitative analysis of for
example the amount of links per year and decade or the
number of links per political party enabling students to
research the mediatisation of Dutch politics in an efficient
manner.</p>
    </sec>
    <sec id="sec-2">
      <title>2. RELATED WORK</title>
      <p>
        The mediatisation of political debates has been the focal
point of a growing field of disciplines, such as television
researchers [
        <xref ref-type="bibr" rid="ref1">1</xref>
        ], communication scientists who are interested
in doing discourse analysis or linguistics [
        <xref ref-type="bibr" rid="ref2">2</xref>
        ] and
psychologists for researching the self-mediation of public
persons [3]. However, due to the lack of available data on
the mediation of the debates on radio and television, the
focus up until now has been on newspapers. Since the
introduction of digital sources that do include radio
newsreels, television newscasts and current affairs
programs, researchers should now be able to make cross
media-comparisons between the different types of
mediaoutlets. To make these large digital sources more accessible
and more connected to each other, we build upon a set of
guidelines and techniques to represent, link and publish
data on the Linked Data Web [
        <xref ref-type="bibr" rid="ref9">10</xref>
        ] using so-called semantic
web technology. In the domain of cultural heritage, the
MultiMedian E-Culture project [
        <xref ref-type="bibr" rid="ref10">11</xref>
        ] has shown that through
explicit representation of links between and within
collections, cross-collection search becomes possible.
Krouf et al. [
        <xref ref-type="bibr" rid="ref11">12</xref>
        ] demonstrate how various online sources of
event information, containing both media and descriptions
of events, can be merged using Linked Data. Noy et al. [
        <xref ref-type="bibr" rid="ref12">13</xref>
        ]
describe how they represent and link hundreds of
biomedical terminologies. In PoliMedia, we apply semantic
web technology to connect various media datasets with a
political event dataset. To find links between datasets that
are so different in nature, we have developed a linking
algorithm that includes named entity recognition and topic
detection. For the latter, we have used an off-the-shelve tool
called Mallet [
        <xref ref-type="bibr" rid="ref13">14</xref>
        ].
      </p>
    </sec>
    <sec id="sec-3">
      <title>3. SYSTEM DESCRIPTION</title>
      <p>The problem PoliMedia aims to resolve is the difficulty of
searching a multitude of archives for cross-media analyses.
In order to resolve this difficulty, we approached it from
two perspectives; 1) the user perspective, and 2) the data
perspective.</p>
      <sec id="sec-3-1">
        <title>The user perspective</title>
        <p>The targeted user groups are primarily students and
researchers of History, Communication and Media, Media
Studies and Sociology of Culture, Media and the Arts.
However, the PoliMedia portal is valuable for a much wider
range of Humanities and Social Sciences students and
researchers who for example analyse the representation of
politicians in the media or discussion of recurring themes.
We also expect the system to be useful for several other
disciplines, such as communication students who are
interested in doing discourse analysis or linguistic aspects
of media and political debates, psychologists researching
the self-mediation of public persons, and even economists
who nowadays pay more attention to the way politicians
talk about the current economic crises. Furthermore, since
all the links are available at data.polimedia.nl this data can
also be used by students and researchers of computer
science or related fields, interested in data analysis and
visualization.</p>
        <p>
          The development of the user interface of PoliMedia was
based on a requirements study with five scholars/lecturers
in history and political communication. The main use case
appeared to be identifying politicians or debates of interest,
and finding their representation in the media for qualitative
analyses. This use case and its requirements were discussed
with a UI-designer, which led to the design of a faceted
search user interface (SUI) as depicted in figure 2. Facets
allow the user to refine search results, they support the
searcher by presenting an overview of the structure of the
collection, as well as provide a transition between browsing
and search strategies [
          <xref ref-type="bibr" rid="ref5">6</xref>
          ].
        </p>
        <p>The SUI consists of three main levels:
1) the landing page where researchers can enter search
terms (figure 1),
2) the results page (figure 2) with the search results, facets
for refinements and a search bar for new queries and
3) the debate page (figure 3) which shows a complete
debate and the linked media items. When clicking on a
media item, the item will be opened in a new screen in its
original lay-out (figure 4).</p>
        <p>
          We evaluated a preliminary version of the interface by
means of an eye tracking study [
          <xref ref-type="bibr" rid="ref6">7</xref>
          ]. This study showed that
the faceted SUI enabled users to perform both known-item
searches, as well as exploratory searches to analyse a topic
over time. However, navigating the debates themselves
proved to be rather difficult; as debates can be dozens of
pages long, it was hard for users to gain an overview of the
debate. To address this issue, the faceted search which was
already available on the search results page (figure 2) was
also introduced on the debate page (figure 3) in the final
version of the interface.
        </p>
      </sec>
      <sec id="sec-3-2">
        <title>The data perspective</title>
        <p>
          In order to allow users to perform cross-media analysis in a
single system, PoliMedia combines three data sources:
parliamentary debates, a newspaper archive and a radio
bulletin archive. The collection of Dutch parliamentary
debates, the so-called Handelingen der Staten-Generaal,
are published by the government in the form of complete
transcripts of the speeches of politicians in parliamentary
debates. For the period 1945-1995, the transcripts of all
9,294 debates that were held are published in unstructured
TXT and PDF format at
http://www.statengeneraaldigitaal.nl. The project ``War in
Parliament'' has transformed them to a fine-grained XML
structure [
          <xref ref-type="bibr" rid="ref3">4</xref>
          ]. We build upon War in Parliament and
translate their XML to RDF. To store, query and link the
debate data, we have created a semantic model in RDF
which is a specialization of the more widely applicable
Simple Event Model (SEM) [
          <xref ref-type="bibr" rid="ref8">9</xref>
          ]. SEM is a model that aims
to represent events on the Web and explicate complicated
semantic relations between people, places, actions and
objects: not only who did what, when and where, but also
the roles each actor played, the time during which this role
is valid, and the authority according to which this role is
assigned. To represent the parliamentary debates in RDF,
we have created a domain specific semantic model as a
specialization of SEM that enables us to express
Handelingen Verenigde
        </p>
        <p>Vergadering...
1945-11-20
dc:source
dc:source
nl.proc.sgd.d.19720000002</p>
        <p>hasSubsequentPartOfDebate
Debate
rdf:type</p>
        <p>PartOfDebate</p>
        <p>rdf:type
nl.proc.sgd.d.
194519460000002.1.2</p>
        <p>sem:hasActor
hasSubsequentSpeech</p>
        <p>
          nl.proc.sgd.d.
194519460000002.1.3
Fig 5: RDF model to represent parliamentary debates and links to media
"De voorzitter
opent de
vergadering…"
"Mijnheer de
Voorzitter, de
Commissie
van …"
information associated with the debates such as topics,
actors, debate structure, and links to media. To increase
reusability of the data, we use Dublin Core properties where
appropriate, for example to denote dates, titles and
publishers of debates. Figure 5 shows the RDF model. For
brevity, we have left the representation of speakers (i.e.
politicians and their party) out. For a detailed description of
the design decisions of the model, we refer to [
          <xref ref-type="bibr" rid="ref4">5</xref>
          ] and [
          <xref ref-type="bibr" rid="ref7">8</xref>
          ].
        </p>
      </sec>
      <sec id="sec-3-3">
        <title>Data Usage</title>
        <p>The newspaper archive as well as the radio bulletin archive
resides at the Dutch Royal Library. To determine links
between debates and the media items in these archives, we
query the full text as well as the metadata through the OAI
protocol. For copyright reasons, the dataset used in the
PoliMedia portal does not contain the media items
themselves or their metadata; only the URIs of the items in
their original archives are included. From the portal, a user
can click a hyperlink to the Royal Library site to view the
requested media item. At the moment, the datasets are
static; they contain the debate transcripts and links to media
archives of the period 1945-1995. In the future, we plan to
include up-to-date data in the form of the latest debate
transcripts and news articles and bulletins.</p>
        <p>
          The basis of PoliMedia lies in the transcripts of the Dutch
parliament from 1814-1995, containing circa 2.5 million
pages of debates with speeches that have been OCR’d and
thus allow for full-text search. The transcripts have been
converted to structured data in XML form in previous
research [
          <xref ref-type="bibr" rid="ref3">4</xref>
          ]. For each speech (i.e. a fragment from a single
speaker in a debate), we extract information to represent
this speech; the speaker, the date, important terms (i.e.
named entities) from its content and important terms from
the description of the debate in which the speech is held.
This information is then combined to create a query with
which we search the archives of the newspapers and radio
bulletins. Media items that correspond to this query are
retrieved, after which a link is created between the speech
and the media item [
          <xref ref-type="bibr" rid="ref4">5</xref>
          ]. The links, as well as the
parliamentary debates are represented as RDF [
          <xref ref-type="bibr" rid="ref7">8</xref>
          ]. These
links are available at data.polimedia.nl as an open dataset
for future researchers.
        </p>
      </sec>
      <sec id="sec-3-4">
        <title>Performance</title>
        <p>
          We created a stable system by using SPARQL to fetch the
relevant debate data from an OWLIM repository that hosts
the PoliMedia dataset. To ensure reasonable response
times, the server hosting the repository has been upgraded
from 8GB to 16GB of memory. Because of OWLIM’s
limited capabilities with respect to full-text and faceted
search a separate SOLR index has been created. SOLR was
chosen because of its widespread use and reputation as a
high performing search index with capabilities for faceted
search and many other optimization options, such as
language specific options to ensure better results for Dutch.
The accuracy of our linking approach was evaluated via a
manual assessment of a sample of 150 links to newspaper
articles. We found that the precision of the algorithm was
good with values around 80%, with an acceptable recall of
62% [
          <xref ref-type="bibr" rid="ref4">5</xref>
          ].
        </p>
      </sec>
      <sec id="sec-3-5">
        <title>Legal &amp; Privacy</title>
        <p>The PoliMedia portal does not involve or store any
userspecific data. Since it is a web-portal, visited URLs may be
stored locally by a user’s own browser. Clicks on
hyperlinks to media items that reside at the servers of the
National library of the Netherlands may be logged by the
library. The original debate data as provided by the Dutch
government has a CC0 licence. The copyrights of the
newspaper articles and radio bulletins are with the original
publishers/broadcasters. This material may be used “for
private use or a user’s own study.”</p>
      </sec>
    </sec>
    <sec id="sec-4">
      <title>4. DISCUSSION</title>
      <p>PoliMedia successfully automatically created links between
the transcriptions of parliamentary debates and newspaper
articles &amp; radio bulletins, demonstrating how two very
different datasets can be connected. In the near future, we
intend to study the generalizability of our linking approach
for linking other datasets, such as online (social) media and
proceedings of other official meetings.</p>
      <p>We already tried to link the debates with television
programmes located at the Netherlands Institute for Sound
and Vision but have not been able to do this. There can be
several reasons for the lack of these links: the size of the
available television dataset, the lack of full-text search in
AV or the suitability of the linking algorithm. We expect
that the metadata contained insufficient information to be
linked to, while the television programs did contain
coverage of the relevant debates. We hypothesize that
linking to audio-visual sources requires other techniques of
opening up AV archives, such as the inclusion of
timebased metadata (e.g. subtitles) or the use of speech and
image recognition. These techniques give more information
about the content of the programs than is described in the
existing metadata. We are currently working on a follow-up
project of PoliMedia in which we aim to link the transcripts
of the European Parliament to television programs of which
the metadata has been enriched with subtitles and speech
recognition to further explore the possibilities of linking to
television programs.</p>
    </sec>
    <sec id="sec-5">
      <title>5. CONCLUSIONS</title>
      <p>The PoliMedia search user interface clearly shows the
potential for students by linking the transcripts of political
debates to different media outlets, allowing cross media
analysis of both newspapers as well as radio items.
However, we did not yet succeed in linking to television
programmes but envision this will be possible in future
research projects that can build upon the knowledge and
insights we gained through the development of the
PoliMedia project.</p>
    </sec>
    <sec id="sec-6">
      <title>ACKNOWLEDGMENTS</title>
      <p>The PoliMedia project was financed by CLARIN-NL and
carried out by an interdisciplinary research team, consisting
of both computer scientists at the TU Delft and VU
Amsterdam, information scientists and historians at the
Erasmus University Rotterdam and programmers at the
Netherlands Institute for Sounds and Vision. We are
grateful for the support of the National Library in providing
the data of both the transcripts of the Dutch parliament as
well as of the newspapers and radio bulletins.
[3] Corner &amp; Pels (2003) Media and the restyling of
politics (London)</p>
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