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  <front>
    <journal-meta />
    <article-meta>
      <title-group>
        <article-title>FTR-18: Collecting rumours on football transfer news</article-title>
      </title-group>
      <contrib-group>
        <contrib contrib-type="author">
          <string-name>Danielle Caled</string-name>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Mario J. Silva</string-name>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <aff id="aff0">
          <label>0</label>
          <institution>INESC-ID Lisboa, Instituto Superior Tecnico, Universidade de Lisboa Lisbon</institution>
          ,
          <country country="PT">Portugal</country>
        </aff>
      </contrib-group>
      <abstract>
        <p>This paper describes ongoing work on the creation of a multilingual rumour dataset on football transfer news, FTR-18. Transfer rumours are continuously published by sports media. They can both harm the image of player or a club or increase the player's market value. The proposed dataset includes transfer articles written in English, Spanish and Portuguese. It also comprises Twitter reactions related to the transfer rumours. FTR-18 is suited for rumour classi cation tasks and allows the research on the linguistic patterns used in sports journalism.</p>
      </abstract>
    </article-meta>
  </front>
  <body>
    <sec id="sec-1">
      <title>-</title>
      <p>
        In the last years, the way news are spread has
changed. Social networks, blogs/micro-blogs and other
untrusted online news sources have gained popularity,
thus allowing any user to produce unveri ed content.
This modern kind of media enables real-time
proliferation of news stories, and, as consequence, increases the
di usion of rumours, hoaxes and misinformation to a
global audience [
        <xref ref-type="bibr" rid="ref7">7</xref>
        ]. As news content is continuously
published online, the speed in which it is disseminated
hinders human fact-checking activity. A piece of
information whose \veracity status is yet to be veri ed at
the time of posting" is called rumour [
        <xref ref-type="bibr" rid="ref14">14</xref>
        ]. News
articles, scienti c researches and conspiracy-theory stories
can oat in the veracity spectrum. They are
characterised by distinct stylistic dimensions and these
features enable their spread, but are orthogonal to their
truthfulness [
        <xref ref-type="bibr" rid="ref9">9</xref>
        ].
      </p>
      <p>
        The football transfer market o ers a fertile ground
for rumour dissemination because rumours and
misCopyright © CIKM 2018 for the individual papers by the papers'
authors. Copyright © CIKM 2018 for the volume as a collection
by its editors. This volume and its papers are published under
information spreads may be motivated by personal
pro t or public harm. Releasing false or misleading
news about alleged moves of players between clubs
emerges as a strategy to increase a player's market
value and transfer fees. Negligent transfer
announcements are assigned to high sums directly related to
some transfers [
        <xref ref-type="bibr" rid="ref4">4</xref>
        ]. In addition, news organisations
also bene t from announcements of alleged transfer
moves, attracting public attention by selling contents
and advertisements. Maia showed that most of the
football transfer news published by the three biggest
Portuguese sports diaries during the Summer of 2015
were not con rmed [
        <xref ref-type="bibr" rid="ref4">4</xref>
        ]. Table 1 provides an example
of a news article about a transfer to Real Madrid that
was latter denied by the club in an o cial
announcement. Both the transfer news and the announcement
were released on July 4, 2018.
      </p>
      <p>According to the Union of European Football
Associations' (UEFA) annual report1, the European
transfer market reached a record revenue of e5.6 billion
during the Summer of 2017, a 6% increase in
spending during this period relatively to the highest value
recorded in the last ten years. Economical side e ects
of rumours on football clubs shares are also reported,
like the rumour of Cristiano Ronaldo joining Juventus
FC, which made the club shares jump almost 10% on
a single day2 before any o cial announcement.</p>
      <p>Motivated by the extensive attention given by
sports media to transfer news and the high amounts
involved, we propose the creation of Football Transfer
Rumours 2018 (FTR-18), a transfer rumours dataset
for researching the linguistic patterns in their text and
propagation mechanisms. FTR-18 is designed as a
multilingual collection of articles published by the
relevant news organisations either in English, Spanish or
Portuguese languages. Besides news articles, our
proposed dataset also comprises Twitter posts associated
to the transfer rumours. The present work describes
the creation process of FTR-18 dataset and discusses
1https://goo.gl/FoAv2g
2https://goo.gl/3wKhj3</p>
      <p>Evidence: Real Madrid o cial announcementb
Extract: Given the information published in the
last few hours regarding an alleged agreement
between Real Madrid C.F. and PSG for the player
Kylian Mbappe, Real Madrid would like to state that
it is completely false.</p>
      <p>Real Madrid has not made any o er to PSG or the
player and condemns the spreading of this type of
information that has not been proven by the parties
concerned.
a https://goo.gl/HhRafF
b https://goo.gl/7oCqBy
the intended usage of the collection.
2</p>
    </sec>
    <sec id="sec-2">
      <title>Related Work</title>
      <p>
        Collections of rumours from di erent natures have
been assembled before. However, these datasets
mainly focused on political and social issues [
        <xref ref-type="bibr" rid="ref10 ref5 ref6">5, 6, 10</xref>
        ].
Some of these datasets were built using rumours
collected from social media platforms [
        <xref ref-type="bibr" rid="ref12 ref13 ref5">5, 12, 13</xref>
        ], such
as Twitter, or with data extracted from fact-checking
websites [
        <xref ref-type="bibr" rid="ref10 ref6">6, 10</xref>
        ], like PolitiFact3 and Snopes4, while
others were crafted using manually created claims
based on Wikipedia articles [
        <xref ref-type="bibr" rid="ref8">8</xref>
        ].
      </p>
      <p>
        The rst large-scale dataset on rumour tracking and
classi cation was proposed by Qazvinian et al. [
        <xref ref-type="bibr" rid="ref5">5</xref>
        ].
This dataset comprises manually annotated Twitter
posts (tweets) from ve political and social
controversial topics, with tweets marked as related or unrelated
to the rumour. It also provides annotations about
users' beliefs towards rumours, i.e., users who endorse
versus users who refute or question a given rumour.
Twitter posts were also used in the construction of
two datasets under the PHEME project [
        <xref ref-type="bibr" rid="ref1">1</xref>
        ]: PHEME
dataset of rumours and non-rumours (PHEME-RNR)
and PHEME rumour scheme dataset (PHEME-RSD).
3http://www.politifact.com/
4https://www.snopes.com/
These two collections are composed of tweets from
rumourous conversations associated with newsworthy
events mainly about crisis situations. PHEME-RNR
contains stories manually annotated as rumour or
nonrumour, hence being suited for the rumour detection
task [
        <xref ref-type="bibr" rid="ref12">12</xref>
        ]. On the other hand, PHEME-RSD was
annotated for stance and veracity, following crowd-sourcing
guidelines [
        <xref ref-type="bibr" rid="ref11">11</xref>
        ], and tracked three dimensions of
interaction expressed by users: support, certainty and
evidentiality [
        <xref ref-type="bibr" rid="ref13">13</xref>
        ]. PHEME-RSD contains conversations
threads in English and in German, however this data
is extremely imbalanced as less than 6% of the tweets
are written in German.
      </p>
      <p>
        Silverman developed a dataset for the analysis of
how online media handles rumours and unveri ed
information [
        <xref ref-type="bibr" rid="ref6">6</xref>
        ]. The resulting Emergent database is a
collection of online rumours comprising topics about
war con icts, politics and business/technology.
Emergent data was generated with the help of automated
tools to identify and capture uncon rmed reports early
in their life-cycle. Then, rumours were classi ed
according to their headline and body text stances and
monitored with respect to social network shares
(Twitter, Facebook and Google Plus) and version changes.
In a posterior work, Ferreira and Vlachos leveraged
Emergent into a dataset focusing veracity estimation
and stance classi cation [
        <xref ref-type="bibr" rid="ref3">3</xref>
        ]. This modi ed dataset
consists of claims and associated news articles
headlines. Claims were labelled with respect to their
veracity, while the news articles headlines were categorised
according to their stances towards the claim:
supporting, denying or observing, if the article does not make
assessments about the veracity the claim.
      </p>
      <p>
        LIAR is another dataset that could be employed
in fact-checking and stance classi cation tasks [
        <xref ref-type="bibr" rid="ref10">10</xref>
        ].
LIAR includes manually labelled short statements
from PolitiFact. All the statements were obtained
from a political context, either extracted from debates,
campaign speeches, social media posts, news releases
or interviews. Each statement was evaluated for its
truthfulness and received a veracity label accompanied
by the corresponding evidences.
      </p>
      <p>
        Thorne et al. developed FEVER (Fact Extraction
and VERi cation), a large-scale manually annotated
dataset focusing on veri cation of claims against
textual sources [
        <xref ref-type="bibr" rid="ref8">8</xref>
        ]. FEVER is composed of claims
generated from modi cations in sentences extracted from
introductory sections of Wikipedia pages. The claims
were manually classi ed as supported, refuted or not
enough info (if no information in Wikipedia can
support or refute the claim). Additional Wikipedia
justication evidences concerning supporting and refuting
sentences were also recorded.
      </p>
      <p>
        The PHEME-RSD and FEVER datasets were
employed in stance detection and veracity prediction
shared tasks. The PHEME-RSD was employed in
the Semantic Evaluation (SemEval) 2017
competition, Task 8 RumourEval5 [
        <xref ref-type="bibr" rid="ref2">2</xref>
        ]. In the rst sub-task
(Sub-task A: Stance Classi cation), participants were
asked to analyse how social media users reacted to
rumourous stories, while for the second sub-task
(Subtask B: Veracity prediction), participants were asked
to predict the veracity of a given rumour. In the
FEVER shared task6, participants should build a
system to extract textual evidences either supporting or
refuting the claim.
      </p>
      <p>Despite the variety of existing datasets for rumour
analysis, none of them addresses football rumours.
Besides, rumours in multilingual environments like the
European Football market are yet to be explored by
the academic research community. For our purpose,
however, it is extremely important to track how news
about transfer rumours are covered by sports media in
di erent languages, as UEFA transfers generally occur
between distinct European countries. Hence, our
proposal di ers from the previous work as it introduces
a new dataset comprising football transfer rumours in
three di erent languages: English, Spanish and
Portuguese.
3</p>
    </sec>
    <sec id="sec-3">
      <title>Dataset building</title>
      <p>The data included in FTR-18 was harvested during the
2018 Summer Transfer Window (STW18). Transfer
windows are periods during the year in which football
clubs can make international transfers. Every league
has the right to choose two annual transfer windows,
with the opening and closing dates being de ned by
the football associations of the league.</p>
      <p>The collected material includes both transfer news
and rumours and the corresponding reactions to these
rumours on Twitter. As we develop a multilingual
dataset containing news and comments in English,
Spanish and Portuguese involving UEFA clubs, the
harvesting is performed during a common period
including the transfer windows of England, Spain and
Portugal. Accordingly, data is being collected from
June 24 until August 31, 2018.</p>
      <p>FTR-18 is built in three stages. First, we browsed
the media and social networks for an initial
assessment of transfer rumours involving top UEFA clubs.
Next, we performed both a semi-automated news
articles harvesting and a Twitter crawling, selecting news
and tweets related to the rumours, respectively.
Finally, as transfer moves are con rmed (or not), we
annotate rumour veracity.</p>
      <p>5http://alt.qcri.org/semeval2017/task8/
6http://fever.ai/task.html
3.1</p>
      <sec id="sec-3-1">
        <title>Football clubs selection</title>
        <p>The rst step in the creation of the FTR-18 is the
selection of the clubs to follow during the Summer
Transfer Window of 2018. We picked English,
Spanish and Portuguese clubs that played the group stage
in 2017-2018 UEFA Champions League. This decision
was made based on the languages we are more familiar
with. With this restriction, we decided to monitor the
following clubs:</p>
        <p>England: Chelsea, Liverpool, Manchester City,
Manchester United, Tottenham Hotspur
Spain: Atletico Madrid, Barcelona, Real Madrid,
Sevilla</p>
        <p>Portugal: Ben ca, Porto, Sporting CP
3.2</p>
      </sec>
      <sec id="sec-3-2">
        <title>Transfer rumours selection</title>
        <p>The next stage of the FTR-18 generation is the
collection of transfer news. We selected transfer rumours
involving the monitored clubs. The rumours included
narratives of permanence or transfer moves concerning
football players, that is, whether players are leaving or
being hired by the monitored clubs. For consistency
reasons, we restricted the rumour selection to players
a liated to clubs from countries having English,
Spanish or Portuguese as their majority language. The
rumours were manually tracked and extracted from
many sports news sources.</p>
        <p>For each rumour, we annotated the target player,
the target's club by the opening of the 2018
Summer Transfer Window (denoted as source), and the
rumoured destination club (See Figure 1). We
considered rumours either about the transference of a target
to another club (source 6= destination) or about the
permanence of the player in the current club (source
= destination).
3.3</p>
      </sec>
      <sec id="sec-3-3">
        <title>News articles harvesting</title>
        <p>News harvesting involved searching and collecting
news articles, published by di erent news
organisations, related to the identi ed rumours in the
lan</p>
        <p>Transfer rumour and news articles
atguages of the dataset. It was performed on a daily
basis during the STW18. Each selected news article is
associated with a single transfer move, and it might
report a rumour or a veri ed information. We restricted
our harvesting to news containing headlines with clear
transfer reports about a single target, even if they
report secondary moves in the body text (e.g. another
player's alleged move, or interest manifested by other
clubs). News with headlines pointing potential
transfer of a player to multiple clubs were discarded.</p>
        <p>For the news collection, we extracted content and
meta-data from each article. Content information
includes headline, subhead, and body text, while for the
meta-data we registered the article source, language,
url and the publication date (See Figure 1). The news
harvesting task is semi-automated, as we could not
build scrapers suited for all news sources due to their
poor CSS structure.
3.4</p>
      </sec>
      <sec id="sec-3-4">
        <title>Rumour reactions crawler</title>
        <p>Once a rumour is identi ed, we build a crawler using
the Twitter's streaming API7 to collect posts related
to the rumour. In compliance to the established
language restrictions, we only harvest tweets written in
the languages of the FTR-18 dataset. We record both
the message content, tweet creation date and the data
associated to the user who posted the message (id,
screen name, description, location, friends and
followers count, veri cation account status ). If the post is
a retweet, we also register the retweet status, the data
associated to the user who posted the original message
and the retweet and favourite counts.</p>
        <p>Besides collecting tweets related to rumours, we also
track Twitter account meta-data and followers
statistics either for the players, for the monitored clubs and
for the clubs involved in the transfer rumours.
3.5</p>
      </sec>
      <sec id="sec-3-5">
        <title>Rumour veracity annotation</title>
        <p>As the rumour unfolds, we annotate the rumour
veracity by adding to the transfer rumour meta-data the
evidences that support or refute the rumour and the
publication date of these evidences. Rumour
veracity is to be inferred until the end of 2018 Summer
Transfer Window. Thus, for the case when source 6=
destination, the rumour veracity is stated as True, if
the transfer is con rmed, or is assigned as False, if the
target remains in the source club or if the target is
transferred to a di erent destination during STW18.
Similarly, for rumours in which source = destination,
the rumour veracity is inferred as False if the player is
transferred, or True otherwise.</p>
        <p>7https://developer.twitter.com/en/docs/tweets/
lterrealtime/overview.html</p>
        <p>
          Despite the challenges of manually determining the
credibility of a rumour [
          <xref ref-type="bibr" rid="ref14">14</xref>
          ], UEFA registration after
STW18 will provide ground truth data for the
annotation of the rumours' veracity.
4
        </p>
      </sec>
    </sec>
    <sec id="sec-4">
      <title>Initial Analysis</title>
      <p>Currently, the FTR-18 dataset comprises 3,045 news
articles and more than 2,064K tweets (See Table 2).
The news articles subset considers transfer news
covered by online sports media written in English (1,517),
Spanish (747) or Portuguese (781) by 96 di erent
news organisations. This collection includes 304
transfer moves associated with 175 target football
players. The Twitter subset contains original messages and
retweets written in English (1,130K), Spanish (677K)
or Portuguese (257K). The Twitter posts are related
to 112 claimed transfer moves involving 84 di erent
football players. The FTR-18 dataset meta-data and
corresponding news source scrapers are available at
https://github.com/dcaled/FTR-18.</p>
      <p>
        In a preliminary analysis of the collected news
articles, we noticed many cross-references between
different news sources. This pattern has already been
identi ed by Silverman [
        <xref ref-type="bibr" rid="ref6">6</xref>
        ] and Maia [
        <xref ref-type="bibr" rid="ref4">4</xref>
        ]. We
observed a constant appearance of attribution
formulations like \source S reported " or \according to source
S ", followed or not by the link to the referred news
source. Other structures used to conceal the
origin of the rumour are \according to reports/sources ",
\are said ", \player P linked to club C ", \reports
suggest ". Expressions like these appear in most of our
collected news articles. Another common strategy is
reporting an unveri ed information using news
headline as a question [
        <xref ref-type="bibr" rid="ref6">6</xref>
        ] (\Ronaldo out, Neymar in at Real
Madrid? 8"). Although less common, this last example
is often adopted, mainly by Spanish media.
      </p>
      <p>Another interesting observation concerning transfer
news is the cascading move chain associated to a
rumour. For example, news sources condition the
acquisition of a new player on the sale of another player by
the same club (\Cristiano Ronaldo open to Juventus
move as Real Madrid consider selling to fund move for
8https://www.theguardian.com/football/2018/jul/03/footballtransfer-rumours-cristiano-ronaldo-real-madrid-juventusneymar
Kylian Mbappe or Neymar 9"). This pattern drives the
reader to expect a continuation of the rumourous story
and its unfoldings, thus keeping audience's attention
for follow-up stories.
5</p>
    </sec>
    <sec id="sec-5">
      <title>Discussion</title>
      <p>
        FTR-18 is suited for most of the steps involved in
a rumour classi cation process, as presented by
Zubiaga et al. [
        <xref ref-type="bibr" rid="ref14">14</xref>
        ]. Table 3 displays a comparison of
FTR-18 against existing datasets, showing used data
sources, availability, multilingual characteristics and
possible usage. At this rst phase of the dataset
development, we perform annotations on rumours
veracity. This task can be nished by the o cial closing
date of STW18 (August 31, 2018), when all football
transfers must be concluded. Any subsequent
transfers are frozen until the next Winter Transfer Window
(January 2019). Once each rumour is labelled on its
truthfulness, rumour veracity assessment could be
performed on the FTR-18 dataset.
      </p>
      <p>In a second annotation phase, we will manually
label our news articles subset, identifying which articles
report rumours and which report veri ed information.
This annotation will make FTR-18 suited for a rumour
detection task. Stance detection is another possible
application for the FTR-18 dataset. The collected
content allows the classi cation of how the news headlines
orient towards a given transfer rumour. Besides news'
stances, we can evaluate the attitudes manifested by
the audience with respect to a transfer move using
reactions to Twitter posts. Both news articles labelling
and stance annotation depend on human judgement.</p>
      <p>
        The collected data also encourages analysis of
rumour tracking. This research topic is scarcely explored
and consists of identifying content associated with a
rumour that is currently monitored [
        <xref ref-type="bibr" rid="ref14">14</xref>
        ]. We intend
to label the harvested news and Twitter posts a
pos9https://www.independent.co.uk/sport/football/transfers/cristianoronaldo-transfer-news-latest-juventus-real-madrid-neymarkylian-mbappe-unveil-move-a8434171.html
      </p>
      <sec id="sec-5-1">
        <title>Publicly</title>
        <p>Available</p>
      </sec>
      <sec id="sec-5-2">
        <title>Multi</title>
        <p>lingual</p>
      </sec>
      <sec id="sec-5-3">
        <title>Usage SC VC ER</title>
        <p>
          teriori as related or unrelated to the rumour,
following Qazvinian et al's approach [
          <xref ref-type="bibr" rid="ref5">5</xref>
          ]. As result, FTR-18
could be used as a rumour dataset suited for binary
classi cation of posts in relation to a rumour.
        </p>
        <p>Finally, the FTR-18 dataset will also allow the
analysis on how football transfer news are reported by the
sports media. The news articles collection will serve
as input for identifying the linguistics structures
employed by journalists in transfer coverage. We expect
to conduct an investigative work on the propagation
patterns present in football transfer news, such as the
recurrent conditional transfer moves and the echo
effect caused by repetitions of unveri ed stories
published by third-party news organisations. Further
improvements in the FTR-18 dataset include the
addition of new football leagues (e.g. CONMEBOL), the
expansion of monitored clubs set and the collection of
data from future transfer windows.</p>
        <sec id="sec-5-3-1">
          <title>Acknowledgements</title>
          <p>This work was supported by FCT, under grant No.
UID/CEC/50021/ 2013.</p>
        </sec>
      </sec>
    </sec>
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