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  <front>
    <journal-meta />
    <article-meta>
      <title-group>
        <article-title>DBMS-KU Approach for Author Pro ling and Deception Detection in Arabic</article-title>
      </title-group>
      <contrib-group>
        <contrib contrib-type="author">
          <string-name>Al Ha z Akbar Maulana Siagian</string-name>
          <xref ref-type="aff" rid="aff1">1</xref>
          <xref ref-type="aff" rid="aff2">2</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Masayoshi Aritsugi</string-name>
          <email>aritsugi@cs.kumamoto-u.ac.jp</email>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <aff id="aff0">
          <label>0</label>
          <institution>Big Data Science and Technology, Faculty of Advanced Science and Technology, Kumamoto University</institution>
          ,
          <country country="JP">Japan</country>
        </aff>
        <aff id="aff1">
          <label>1</label>
          <institution>Computer Science and Electrical Engineering, Graduate School of Science and Technology, Kumamoto University</institution>
          ,
          <country country="JP">Japan</country>
        </aff>
        <aff id="aff2">
          <label>2</label>
          <institution>Indonesian Institute of Sciences</institution>
          ,
          <country country="ID">Indonesia</country>
        </aff>
      </contrib-group>
      <abstract>
        <p>This paper presents DBMS-KU team approach for task 1, i.e., author pro ling in Arabic tweets, and task 2, viz., deception detection in Arabic texts, of Author Pro ling and Deception Detection in Arabic (APDA). Our approach utilizes word n-grams, character ngrams, word and character n-grams combinations, and function words as features for classi ers to deal with these two tasks. We then examine several term frequency thresholds to attributes of the features. Our obtained results indicated that our approach could work well in both tasks of this APDA.</p>
      </abstract>
      <kwd-group>
        <kwd>Author pro ling Deception detection Character n-grams Word and character n-grams combinations Function words</kwd>
      </kwd-group>
    </article-meta>
  </front>
  <body>
    <sec id="sec-1">
      <title>-</title>
      <p>This paper elucidates the participation of DBMS-KU team in Author Pro ling
and Deception Detection in Arabic (APDA) of Forum for Information Retrieval
and Evaluation (FIRE) 2019. In this APDA, we participate in task 1, i.e., author
pro ling (gender, age, and variety) in Arabic tweets, and task 2, viz., deception
detection (lie or truth) in Arabic texts (twitter and news) [2, 13{20, 25, 26]. To
do this, we utilize word n-grams, character n-grams, word and character n-grams
combinations, and function words as features for classi ers. Previous studies have
shown that using those features for classi ers could contribute well in author
pro ling and deception detection tasks [1{4, 7{11, 13, 20, 22{24]. To improve our
classi cation performance, we perform particular preprocessing techniques to
the dataset and apply term frequency thresholds to attributes of our utilized
features in this work. Our obtained results could show encouraging evaluation
scores in both tasks of the APDA.</p>
    </sec>
    <sec id="sec-2">
      <title>Dataset 3</title>
    </sec>
    <sec id="sec-3">
      <title>Method</title>
      <p>
        The APDA organizer provided dataset that consisted of training and testing
sets for each task 1 and task 2 [2, 13{20, 25, 26]. The training and testing sets
of task 1 consisted of 2250 and 720 tweets, respectively. In task 2, the training
sets consisted of 532 instances for twitter and 1443 instances for news, while the
testing ones had 241 instances for twitter and 370 instances for news.
This section explains the employed features, term frequency thresholds,
preprocessing, and classi ers in our approach to deal with task 1 and task 2 of the
APDA. To examine the performance of our approach, we conduct 10 fold
crossvalidation in our experiments. Accuracy and F1-score are used to measure the
performance of our approach in task 1 and task 2, respectively. This
measurement is the same as the evaluation metric used by the APDA organizer [
        <xref ref-type="bibr" rid="ref16">16</xref>
        ].
3.1
      </p>
      <sec id="sec-3-1">
        <title>Features</title>
        <p>Word N-grams We use the word n-grams, namely, unigrams (uni), unigrams +
bigrams (2grams), and unigrams + bigrams + trigrams (3grams), as our features
to deal with both tasks in this work. Our word n-grams features are segregated
by space(s) and excluding numbers.</p>
        <p>Character N-grams In this work, we examine character n-grams features
where n is between 3 (3chars) and 15 (15chars). The character n-grams features
are constructed from all existing characters in the dataset.</p>
      </sec>
      <sec id="sec-3-2">
        <title>Word and Character N-grams Combinations To use word and character</title>
        <p>
          n-grams combinations as features, we follow the method of [
          <xref ref-type="bibr" rid="ref22 ref24">22, 24</xref>
          ]. For simplicity,
we consider combining word n-grams, i.e., uni, 2grams, and 3grams, with only the
best character ones as our combinations features in this work, e.g., uni+3chars,
2grams+3chars, and 3grams+3chars.
        </p>
        <p>
          Function Words To deal with this APDA, we utilize a set of 248 Arabic
function words (AFW) from [
          <xref ref-type="bibr" rid="ref12">12</xref>
          ] as features. Following the work of [
          <xref ref-type="bibr" rid="ref23 ref24 ref6">6, 23, 24</xref>
          ],
we employ the AFW features as combinations with our other utilized features
in this work, e.g., uni+AFW, 3chars+AFW, and uni+3chars+AFW.
3.2
        </p>
      </sec>
      <sec id="sec-3-3">
        <title>Term Frequency Thresholds</title>
        <p>
          We examine several term frequency thresholds to attributes of our utilized
features. This examination is to optimize the use of features [
          <xref ref-type="bibr" rid="ref13 ref7">7, 13</xref>
          ] when used by
classi ers in this work. The examined value of the term frequency thresholds
(TH) of the features in this work is from 1 to 10, e.g., uni TH2, 3char TH2, and
uni TH2+3chars TH2.
        </p>
      </sec>
      <sec id="sec-3-4">
        <title>Preprocessing</title>
        <p>
          To improve the classi cation performance [
          <xref ref-type="bibr" rid="ref13 ref7 ref8">7, 8, 13</xref>
          ], we perform certain
preprocessing techniques to the dataset of task 1 and task 2. In task 1, we consider
three preprocessing options, namely, removing all mentioned @users (No@user),
removing all mentioned @users and URLs (No@user-url), and using Arabic
alphabets (Arabic-only). Meanwhile, we use all contents in the dataset and replace
all numbers by zero [
          <xref ref-type="bibr" rid="ref8">8</xref>
          ], e.g., 2020 replaced by 0000, (To-zero) as our
preprocessing choice in task 2. The di erent preprocessing considerations between task 1
and task 2 are not only because of the di erent purpose of classi cation tasks
but also due to the di erent characteristic of each dataset in task 1 and task 2.
3.4
        </p>
      </sec>
      <sec id="sec-3-5">
        <title>Classi ers</title>
        <p>
          We utilize Support Vector Machine (SVM), Naive Bayes (NB), and Multinomial
Naive Bayes (MNB) classi ers in this work. To do this, we use the WEKA [
          <xref ref-type="bibr" rid="ref5">5</xref>
          ]
implementation of those classi ers.
4
        </p>
      </sec>
    </sec>
    <sec id="sec-4">
      <title>Experimental Settings and Results</title>
      <p>We show our experimental settings and obtained results in our submissions for
classifying testing sets of task 1 in Tables 1 and 2, respectively. In this task 1,
using DBMS-KU.2 settings could perform a better classi cation for gender and
age, while utilizing DBMS-KU.3 ones could perform the best classi cation for
variety. These good results might be due to the used preprocessing techniques,
i.e., No@user for gender, No@user-url for age, and Arabic-only for variety, to our
utilized features in this task 1. This conjecture might be corroborated by our
nding that the obtained variety classi cation results of using Arabic-only
preprocessing options, i.e., DBMS-KU.1 and DBMS-KU.3, were better than those
of using No@user-url ones, viz. DBMS-KU.2 (Table 2). Nevertheless, it would
be valuable to analyze further this supposition in the future.</p>
      <p>Next, we display the used experimental settings and obtained results in our
submissions for classifying testing sets of task 2 in Tables 3 and 4, respectively.
According to the results in Table 4, our DBMS-KU.2 settings could perform
better than other ones, i.e., DBMS-KU.1 and DBMS-KU.3, for detecting
deception in both twitter and news of this task 2. This DBMS-KU.2 achievement
might be due to the ability of word and character n-grams combinations features
which was better to capture deception attributes than that of character n-grams,
i.e., DBMS-KU.1, and character n-grams combined with Arabic function words
(AFW) ones, viz., DBMS-KU.3. However, it should be worthwhile to investigate
further of this presumption in the future.
5</p>
    </sec>
    <sec id="sec-5">
      <title>Conclusion</title>
      <p>
        This paper has described the participation of DBMS-KU team in task 1 and
task 2 of the APDA of FIRE 2019. Our obtained results indicated that our
approach could be useful and give promising evaluation scores in both tasks of
this APDA. As future work, examining more various preprocessing techniques to
the dataset, such as in [
        <xref ref-type="bibr" rid="ref8">8</xref>
        ], and using other types of character n-grams features,
e.g., character n-grams in token [
        <xref ref-type="bibr" rid="ref1 ref2">1, 2</xref>
        ] and typed character n-grams [
        <xref ref-type="bibr" rid="ref20 ref21 ref7 ref8">7, 8, 20, 21</xref>
        ],
must be valuable to improve the performance of our approach.
      </p>
      <p>Acknowledgment A.H.A.M. Siagian thanks RISET-Pro (Research and
Innovation in Science and Technology Project) KEMENRISTEKDIKTI (Ministry
of Research, Technology and Higher Education of the Republic of Indonesia)
scholarship for his study.</p>
    </sec>
  </body>
  <back>
    <ref-list>
      <ref id="ref1">
        <mixed-citation>
          1.
          <string-name>
            <surname>Cagnina</surname>
            ,
            <given-names>L.</given-names>
          </string-name>
          ,
          <string-name>
            <surname>Rosso</surname>
            ,
            <given-names>P.</given-names>
          </string-name>
          :
          <article-title>Classi cation of deceptive opinions using a low dimensionality representation</article-title>
          .
          <source>In: Proceedings of the 6th Workshop on Computational Approaches</source>
          to Subjectivity,
          <article-title>Sentiment and Social Media Analysis</article-title>
          . pp.
          <volume>58</volume>
          {
          <fpage>66</fpage>
          . WASSA@EMNLP 2015,
          <article-title>Association for Computational Linguistics</article-title>
          , Stroudsburg, PA, USA (
          <year>2015</year>
          ). https://doi.org/10.18653/v1/
          <fpage>W15</fpage>
          -2909
        </mixed-citation>
      </ref>
      <ref id="ref2">
        <mixed-citation>
          2.
          <string-name>
            <surname>Cagnina</surname>
            ,
            <given-names>L.</given-names>
          </string-name>
          ,
          <string-name>
            <surname>Rosso</surname>
            ,
            <given-names>P.</given-names>
          </string-name>
          :
          <article-title>Detecting deceptive opinions: Intra and cross-domain classi cation using an e cient representation</article-title>
          .
          <source>International Journal of Uncertainty, Fuzziness and Knowledge-Based Systems 25(Supplement-2)</source>
          ,
          <volume>151</volume>
          {
          <fpage>174</fpage>
          (
          <year>2017</year>
          ). https://doi.org/10.1142/S0218488517400165
        </mixed-citation>
      </ref>
      <ref id="ref3">
        <mixed-citation>
          3.
          <string-name>
            <surname>Fusilier</surname>
            ,
            <given-names>D.H.</given-names>
          </string-name>
          ,
          <article-title>Montes-y-</article-title>
          <string-name>
            <surname>Gomez</surname>
            ,
            <given-names>M.</given-names>
          </string-name>
          ,
          <string-name>
            <surname>Rosso</surname>
            ,
            <given-names>P.</given-names>
          </string-name>
          ,
          <string-name>
            <surname>Cabrera</surname>
          </string-name>
          , R.G.:
          <article-title>Detecting positive and negative deceptive opinions using pu-learning</article-title>
          .
          <source>Information Processing and Management</source>
          <volume>51</volume>
          (
          <issue>4</issue>
          ),
          <volume>433</volume>
          {
          <fpage>443</fpage>
          (
          <year>2015</year>
          ). https://doi.org/10.1016/j.ipm.
          <year>2014</year>
          .
          <volume>11</volume>
          .001
        </mixed-citation>
      </ref>
      <ref id="ref4">
        <mixed-citation>
          4.
          <string-name>
            <surname>Fusilier</surname>
            ,
            <given-names>D.H.</given-names>
          </string-name>
          ,
          <article-title>Montes-y-</article-title>
          <string-name>
            <surname>Gomez</surname>
            ,
            <given-names>M.</given-names>
          </string-name>
          ,
          <string-name>
            <surname>Rosso</surname>
            ,
            <given-names>P.</given-names>
          </string-name>
          ,
          <string-name>
            <surname>Cabrera</surname>
          </string-name>
          , R.G.:
          <article-title>Detection of opinion spam with character n-grams</article-title>
          .
          <source>In: International Conference on Intelligent Text Processing and Computational Linguistics</source>
          . pp.
          <volume>285</volume>
          {
          <fpage>294</fpage>
          .
          <source>CICLing 2015</source>
          , Springer International Publishing (
          <year>2015</year>
          ). https://doi.org/10.1007/978-3-
          <fpage>319</fpage>
          -18117-2 21
        </mixed-citation>
      </ref>
      <ref id="ref5">
        <mixed-citation>
          5.
          <string-name>
            <surname>Hall</surname>
            ,
            <given-names>M.</given-names>
          </string-name>
          ,
          <string-name>
            <surname>Frank</surname>
            ,
            <given-names>E.</given-names>
          </string-name>
          ,
          <string-name>
            <surname>Holmes</surname>
            ,
            <given-names>G.</given-names>
          </string-name>
          ,
          <string-name>
            <surname>Pfahringer</surname>
            ,
            <given-names>B.</given-names>
          </string-name>
          ,
          <string-name>
            <surname>Reutemann</surname>
            ,
            <given-names>P.</given-names>
          </string-name>
          ,
          <string-name>
            <surname>Witten</surname>
            ,
            <given-names>I.H.</given-names>
          </string-name>
          :
          <article-title>The weka data mining software: An update</article-title>
          .
          <source>SIGKDD Explor. Newsl</source>
          .
          <volume>11</volume>
          (
          <issue>1</issue>
          ),
          <volume>10</volume>
          {
          <fpage>18</fpage>
          (
          <year>2009</year>
          ). https://doi.org/10.1145/1656274.1656278
        </mixed-citation>
      </ref>
      <ref id="ref6">
        <mixed-citation>
          6.
          <string-name>
            <surname>Markov</surname>
            ,
            <given-names>I.</given-names>
          </string-name>
          ,
          <string-name>
            <surname>Chen</surname>
            ,
            <given-names>L.</given-names>
          </string-name>
          ,
          <string-name>
            <surname>Strapparava</surname>
            ,
            <given-names>C.</given-names>
          </string-name>
          ,
          <string-name>
            <surname>Sidorov</surname>
            ,
            <given-names>G.</given-names>
          </string-name>
          :
          <article-title>CIC-FBK approach to native language identi cation</article-title>
          .
          <source>In: Proceedings of the 12th Workshop on Innovative Use of NLP for Building Educational Applications</source>
          . pp.
          <volume>374</volume>
          {
          <fpage>381</fpage>
          . BEA 2017,
          <article-title>Association for Computational Linguistics</article-title>
          , Stroudsburg, PA, USA (
          <year>2017</year>
          ). https://doi.org/10.18653/v1/
          <fpage>W17</fpage>
          -5042
        </mixed-citation>
      </ref>
      <ref id="ref7">
        <mixed-citation>
          7.
          <string-name>
            <surname>Markov</surname>
            ,
            <given-names>I.</given-names>
          </string-name>
          ,
          <string-name>
            <surname>Gomez-Adorno</surname>
            ,
            <given-names>H.</given-names>
          </string-name>
          ,
          <string-name>
            <surname>Sidorov</surname>
            ,
            <given-names>G.</given-names>
          </string-name>
          :
          <article-title>Language- and subtask-dependent feature selection and classi er parameter tuning for author pro ling</article-title>
          .
          <source>In: Working Notes of CLEF 2017 - Conference and Labs of the Evaluation Forum. CLEF</source>
          <year>2017</year>
          , http://ceur-ws.
          <source>org/</source>
          Vol-1866/paper 96.pdf
        </mixed-citation>
      </ref>
      <ref id="ref8">
        <mixed-citation>
          8.
          <string-name>
            <surname>Markov</surname>
            ,
            <given-names>I.</given-names>
          </string-name>
          ,
          <string-name>
            <surname>Stamatatos</surname>
            ,
            <given-names>E.</given-names>
          </string-name>
          ,
          <string-name>
            <surname>Sidorov</surname>
          </string-name>
          , G.:
          <article-title>Improving cross-topic authorship attribution: The role of pre-processing</article-title>
          .
          <source>In: Computational Linguistics and Intelligent Text Processing</source>
          . pp.
          <volume>289</volume>
          {
          <fpage>302</fpage>
          . Springer International Publishing,
          <string-name>
            <surname>Cham</surname>
          </string-name>
          (
          <year>2018</year>
          ). https://doi.org/10.1007/978-3-
          <fpage>319</fpage>
          -77116-8 21
        </mixed-citation>
      </ref>
      <ref id="ref9">
        <mixed-citation>
          9.
          <string-name>
            <surname>Mukherjee</surname>
            ,
            <given-names>A.</given-names>
          </string-name>
          ,
          <string-name>
            <surname>Venkataraman</surname>
            ,
            <given-names>V.</given-names>
          </string-name>
          ,
          <string-name>
            <surname>Liu</surname>
            ,
            <given-names>B.</given-names>
          </string-name>
          ,
          <string-name>
            <surname>Glance</surname>
          </string-name>
          , N.:
          <article-title>What yelp fake review lter might be doing?</article-title>
          <source>In: International AAAI Conference on Web and Social Media. ICWSM-2013</source>
          (
          <year>2013</year>
          ), https://www.aaai.org/ocs/index.php/ICWSM/ICWSM13/paper/view/6006
        </mixed-citation>
      </ref>
      <ref id="ref10">
        <mixed-citation>
          10.
          <string-name>
            <surname>Ott</surname>
            ,
            <given-names>M.</given-names>
          </string-name>
          ,
          <string-name>
            <surname>Cardie</surname>
            ,
            <given-names>C.</given-names>
          </string-name>
          ,
          <string-name>
            <surname>Hancock</surname>
            ,
            <given-names>J.T.</given-names>
          </string-name>
          :
          <article-title>Negative deceptive opinion spam</article-title>
          .
          <source>In: Proceedings of the 2013 Conference of the North American Chapter of the Association for Computational Linguistics: Human Language Technologies</source>
          . pp.
          <volume>497</volume>
          {
          <fpage>501</fpage>
          . NAACLHLT 2013,
          <article-title>Association for Computational Linguistics</article-title>
          , Stroudsburg, PA, USA (
          <year>2013</year>
          ), https://www.cs.cornell.edu/home/cardie/papers/NAACL13-Negative.pdf
        </mixed-citation>
      </ref>
      <ref id="ref11">
        <mixed-citation>
          11.
          <string-name>
            <surname>Ott</surname>
            ,
            <given-names>M.</given-names>
          </string-name>
          ,
          <string-name>
            <surname>Choi</surname>
            ,
            <given-names>Y.</given-names>
          </string-name>
          ,
          <string-name>
            <surname>Cardie</surname>
            ,
            <given-names>C.</given-names>
          </string-name>
          ,
          <string-name>
            <surname>Hancock</surname>
            ,
            <given-names>J.T.</given-names>
          </string-name>
          :
          <article-title>Finding deceptive opinion spam by any stretch of the imagination</article-title>
          .
          <source>In: Proceedings of the 49th Annual Meeting of the Association for Computational Linguistics: Human Language Technologies - Volume 1</source>
          . pp.
          <volume>309</volume>
          {
          <fpage>319</fpage>
          .
          <string-name>
            <surname>ACL-HLT</surname>
            <given-names>2011</given-names>
          </string-name>
          ,
          <article-title>Association for Computational Linguistics</article-title>
          , Stroudsburg, PA, USA (
          <year>2011</year>
          ), http://dl.acm.org/citation.cfm?id=
          <volume>2002472</volume>
          .
          <fpage>2002512</fpage>
        </mixed-citation>
      </ref>
      <ref id="ref12">
        <mixed-citation>
          12.
          <string-name>
            <surname>Pedregosa</surname>
            ,
            <given-names>F.</given-names>
          </string-name>
          ,
          <string-name>
            <surname>Varoquaux</surname>
            ,
            <given-names>G.</given-names>
          </string-name>
          ,
          <string-name>
            <surname>Gramfort</surname>
            ,
            <given-names>A.</given-names>
          </string-name>
          ,
          <string-name>
            <surname>Michel</surname>
            ,
            <given-names>V.</given-names>
          </string-name>
          ,
          <string-name>
            <surname>Thirion</surname>
            ,
            <given-names>B.</given-names>
          </string-name>
          ,
          <string-name>
            <surname>Grisel</surname>
            ,
            <given-names>O.</given-names>
          </string-name>
          ,
          <string-name>
            <surname>Blondel</surname>
            ,
            <given-names>M.</given-names>
          </string-name>
          ,
          <string-name>
            <surname>Prettenhofer</surname>
            ,
            <given-names>P.</given-names>
          </string-name>
          ,
          <string-name>
            <surname>Weiss</surname>
            ,
            <given-names>R.</given-names>
          </string-name>
          ,
          <string-name>
            <surname>Dubourg</surname>
            ,
            <given-names>V.</given-names>
          </string-name>
          ,
          <string-name>
            <surname>Vanderplas</surname>
            ,
            <given-names>J.</given-names>
          </string-name>
          ,
          <string-name>
            <surname>Passos</surname>
            ,
            <given-names>A.</given-names>
          </string-name>
          ,
          <string-name>
            <surname>Cournapeau</surname>
            ,
            <given-names>D.</given-names>
          </string-name>
          ,
          <string-name>
            <surname>Brucher</surname>
            ,
            <given-names>M.</given-names>
          </string-name>
          ,
          <string-name>
            <surname>Perrot</surname>
            ,
            <given-names>M.</given-names>
          </string-name>
          ,
          <string-name>
            <surname>Duchesnay</surname>
          </string-name>
          , E.: Scikitlearn:
          <article-title>Machine learning in python</article-title>
          .
          <source>J. Mach. Learn. Res</source>
          .
          <volume>12</volume>
          ,
          <issue>2825</issue>
          {
          <fpage>2830</fpage>
          (
          <year>2011</year>
          ), http://dl.acm.org/citation.cfm?id=
          <volume>1953048</volume>
          .
          <fpage>2078195</fpage>
        </mixed-citation>
      </ref>
      <ref id="ref13">
        <mixed-citation>
          13.
          <string-name>
            <surname>Rangel</surname>
            ,
            <given-names>F.</given-names>
          </string-name>
          ,
          <string-name>
            <surname>Franco-Salvador</surname>
            ,
            <given-names>M.</given-names>
          </string-name>
          ,
          <string-name>
            <surname>Rosso</surname>
            ,
            <given-names>P.:</given-names>
          </string-name>
          <article-title>A low dimensionality representation for language variety identi cation</article-title>
          .
          <source>In: Proc. of the 17th Int. Conf. on Intelligent Text Processing and Computational Linguistics</source>
          . pp.
          <volume>156</volume>
          {
          <fpage>169</fpage>
          .
          <source>CICLing</source>
          <year>2016</year>
          , SpringerVerlag (
          <year>2018</year>
          ). https://doi.org/10.1007/978-3-
          <fpage>319</fpage>
          -75487-1 13
        </mixed-citation>
      </ref>
      <ref id="ref14">
        <mixed-citation>
          14.
          <string-name>
            <surname>Rangel</surname>
            ,
            <given-names>F.</given-names>
          </string-name>
          ,
          <string-name>
            <surname>Rosso</surname>
            ,
            <given-names>P.</given-names>
          </string-name>
          :
          <article-title>On the impact of emotions on author proling</article-title>
          .
          <source>Information Processing and Management</source>
          <volume>52</volume>
          (
          <issue>1</issue>
          ),
          <volume>73</volume>
          {
          <fpage>92</fpage>
          (
          <year>2016</year>
          ). https://doi.org/https://doi.org/10.1016/j.ipm.
          <year>2015</year>
          .
          <volume>06</volume>
          .003
        </mixed-citation>
      </ref>
      <ref id="ref15">
        <mixed-citation>
          15.
          <string-name>
            <surname>Rangel</surname>
            ,
            <given-names>F.</given-names>
          </string-name>
          ,
          <string-name>
            <surname>Rosso</surname>
            ,
            <given-names>P.</given-names>
          </string-name>
          ,
          <string-name>
            <surname>Char</surname>
            ,
            <given-names>A.</given-names>
          </string-name>
          ,
          <string-name>
            <surname>Zaghouani</surname>
            ,
            <given-names>W.</given-names>
          </string-name>
          :
          <article-title>Detecting deceptive tweets in arabic for cyber-security</article-title>
          .
          <source>In: Proceedings of the 17th IEEE International Conference on Intelligence and Security Informatics. ISI</source>
          , IEEE, New York, NY, USA (
          <year>2019</year>
          )
        </mixed-citation>
      </ref>
      <ref id="ref16">
        <mixed-citation>
          16.
          <string-name>
            <surname>Rangel</surname>
            ,
            <given-names>F.</given-names>
          </string-name>
          ,
          <string-name>
            <surname>Rosso</surname>
            ,
            <given-names>P.</given-names>
          </string-name>
          ,
          <string-name>
            <surname>Char</surname>
            ,
            <given-names>A.</given-names>
          </string-name>
          ,
          <string-name>
            <surname>Zaghouani</surname>
            ,
            <given-names>W.</given-names>
          </string-name>
          ,
          <string-name>
            <surname>Ghanem</surname>
            ,
            <given-names>B.</given-names>
          </string-name>
          ,
          <string-name>
            <surname>Sanchez-Junquera</surname>
            ,
            <given-names>J.</given-names>
          </string-name>
          :
          <article-title>Overview of the track on author pro ling and deception detection in arabic</article-title>
          . In: Mehta P.,
          <string-name>
            <surname>Rosso</surname>
            <given-names>P.</given-names>
          </string-name>
          ,
          <string-name>
            <surname>Majumder</surname>
            <given-names>P.</given-names>
          </string-name>
          ,
          <string-name>
            <surname>Mitra</surname>
            <given-names>M</given-names>
          </string-name>
          . (Eds.)
          <article-title>Working Notes of the Forum for Information Retrieval Evaluation (FIRE 2019)</article-title>
          .
          <source>CEUR Workshop Proceedings. CEUR-WS.org, Kolkata, India, December</source>
          <volume>12</volume>
          -
          <fpage>15</fpage>
          (
          <year>2019</year>
          )
        </mixed-citation>
      </ref>
      <ref id="ref17">
        <mixed-citation>
          17.
          <string-name>
            <surname>Rangel</surname>
            ,
            <given-names>F.</given-names>
          </string-name>
          ,
          <string-name>
            <surname>Rosso</surname>
            ,
            <given-names>P.</given-names>
          </string-name>
          ,
          <string-name>
            <surname>Chugur</surname>
            ,
            <given-names>I.</given-names>
          </string-name>
          ,
          <string-name>
            <surname>Potthast</surname>
            ,
            <given-names>M.</given-names>
          </string-name>
          ,
          <string-name>
            <surname>Trenkmann</surname>
            ,
            <given-names>M.</given-names>
          </string-name>
          ,
          <string-name>
            <surname>Stein</surname>
            ,
            <given-names>B.</given-names>
          </string-name>
          ,
          <string-name>
            <surname>Verhoeven</surname>
            ,
            <given-names>B.</given-names>
          </string-name>
          ,
          <string-name>
            <surname>Daelemans</surname>
            ,
            <given-names>W.</given-names>
          </string-name>
          :
          <article-title>Overview of the author pro ling task at PAN 2014</article-title>
          . In: Cappellato L.,
          <string-name>
            <surname>Ferro</surname>
            <given-names>N.</given-names>
          </string-name>
          ,
          <string-name>
            <surname>Halvey</surname>
            <given-names>M.</given-names>
          </string-name>
          ,
          <string-name>
            <surname>Kraaij</surname>
            <given-names>W</given-names>
          </string-name>
          . (Eds.)
          <article-title>CLEF 2014 Labs and Workshops, Notebook Papers</article-title>
          . pp.
          <volume>898</volume>
          {
          <issue>927</issue>
          (
          <year>2014</year>
          ), http://ceur-ws.org/Vol1180/CLEF2014wn-Pan-RangelEt2014.pdf
        </mixed-citation>
      </ref>
      <ref id="ref18">
        <mixed-citation>
          18.
          <string-name>
            <surname>Rangel</surname>
            ,
            <given-names>F.</given-names>
          </string-name>
          ,
          <string-name>
            <surname>Rosso</surname>
            ,
            <given-names>P.</given-names>
          </string-name>
          ,
          <string-name>
            <surname>Potthast</surname>
            ,
            <given-names>M.</given-names>
          </string-name>
          ,
          <string-name>
            <surname>Stein</surname>
            ,
            <given-names>B.</given-names>
          </string-name>
          :
          <article-title>Overview of the 5th author pro ling task at PAN 2017: Gender and language variety identi cation in twitter</article-title>
          . In: Cappellato L.,
          <string-name>
            <surname>Ferro</surname>
            <given-names>N.</given-names>
          </string-name>
          ,
          <string-name>
            <surname>Goeuriot</surname>
            <given-names>L</given-names>
          </string-name>
          ,
          <string-name>
            <surname>Mandl</surname>
            <given-names>T</given-names>
          </string-name>
          . (Eds.)
          <article-title>CLEF 2017 Labs and Workshops, Notebook Papers</article-title>
          .
          <source>CEUR Workshop Proceedings</source>
          (
          <year>2017</year>
          ), http://ceur-ws.org/Vol1866/invited paper 11.pdf
        </mixed-citation>
      </ref>
      <ref id="ref19">
        <mixed-citation>
          19.
          <string-name>
            <surname>Rosso</surname>
            ,
            <given-names>P.</given-names>
          </string-name>
          ,
          <string-name>
            <surname>Rangel</surname>
            ,
            <given-names>F.</given-names>
          </string-name>
          ,
          <string-name>
            <surname>Hernandez-Far as</surname>
          </string-name>
          , I.,
          <string-name>
            <surname>Cagnina</surname>
            ,
            <given-names>L.</given-names>
          </string-name>
          ,
          <string-name>
            <surname>Zaghouani</surname>
            ,
            <given-names>W.</given-names>
          </string-name>
          ,
          <string-name>
            <surname>Char</surname>
            ,
            <given-names>A.</given-names>
          </string-name>
          :
          <article-title>A survey on author pro ling, deception, and irony detection for the arabic language</article-title>
          .
          <source>Language and Linguistics Compass</source>
          <volume>12</volume>
          (
          <issue>4</issue>
          ),
          <year>e12275</year>
          (
          <year>2018</year>
          ). https://doi.org/10.1111/lnc3.12275
        </mixed-citation>
      </ref>
      <ref id="ref20">
        <mixed-citation>
          20.
          <string-name>
            <surname>Sanchez-Junquera</surname>
            ,
            <given-names>J.</given-names>
          </string-name>
          ,
          <article-title>Villasen~or-</article-title>
          <string-name>
            <surname>Pineda</surname>
            ,
            <given-names>L.</given-names>
          </string-name>
          ,
          <string-name>
            <surname>Montes-</surname>
            y-Gomez,
            <given-names>M.</given-names>
          </string-name>
          ,
          <string-name>
            <surname>Rosso</surname>
            ,
            <given-names>P.</given-names>
          </string-name>
          :
          <article-title>Character n-grams for detecting deceptive controversial opinions</article-title>
          .
          <source>In: Experimental IR Meets Multilinguality, Multimodality, and Interaction - Proc. of the 9th Int. Conf. of the CLEF Association</source>
          . pp.
          <volume>135</volume>
          {
          <fpage>140</fpage>
          . CLEF 2018, Springer-Verlag (
          <year>2018</year>
          ). https://doi.org/10.1007/978-3-
          <fpage>319</fpage>
          -98932-7 13
        </mixed-citation>
      </ref>
      <ref id="ref21">
        <mixed-citation>
          21.
          <string-name>
            <surname>Sapkota</surname>
            ,
            <given-names>U.</given-names>
          </string-name>
          ,
          <string-name>
            <surname>Bethard</surname>
            ,
            <given-names>S.</given-names>
          </string-name>
          ,
          <string-name>
            <surname>Montes-</surname>
            y-Gomez,
            <given-names>M.</given-names>
          </string-name>
          ,
          <string-name>
            <surname>Solorio</surname>
            ,
            <given-names>T.</given-names>
          </string-name>
          :
          <article-title>Not all character n-grams are created equal: A study in authorship attribution</article-title>
          .
          <source>In: Proceedings of the 2015 Conference of the North American Chapter of the Association for Computational Linguistics: Human Language Technologies</source>
          . pp.
          <volume>93</volume>
          {
          <fpage>102</fpage>
          . NAACLHLT 2015,
          <article-title>Association for Computational Linguistics</article-title>
          , Denver, Colorado (
          <year>2015</year>
          ). https://doi.org/10.3115/v1/
          <fpage>N15</fpage>
          -1010
        </mixed-citation>
      </ref>
      <ref id="ref22">
        <mixed-citation>
          22.
          <string-name>
            <surname>Siagian</surname>
            ,
            <given-names>A.H.A.M.</given-names>
          </string-name>
          ,
          <string-name>
            <surname>Aritsugi</surname>
            ,
            <given-names>M.:</given-names>
          </string-name>
          <article-title>Combining word and character n-grams for detecting deceptive opinions</article-title>
          .
          <source>In: 2017 IEEE 41st Annual Computer Software and Applications Conference</source>
          . pp.
          <volume>828</volume>
          {
          <fpage>833</fpage>
          . COMPSAC, IEEE Computer Society, Washington, DC, USA (
          <year>2017</year>
          ). https://doi.org/10.1109/COMPSAC.
          <year>2017</year>
          .90
        </mixed-citation>
      </ref>
      <ref id="ref23">
        <mixed-citation>
          23.
          <string-name>
            <surname>Siagian</surname>
            ,
            <given-names>A.H.A.M.</given-names>
          </string-name>
          ,
          <string-name>
            <surname>Aritsugi</surname>
            ,
            <given-names>M.</given-names>
          </string-name>
          :
          <article-title>Exploiting function words feature in classifying deceptive and truthful reviews</article-title>
          .
          <source>In: 2018 Thirteenth International Conference on Digital Information Management</source>
          . pp.
          <volume>51</volume>
          {
          <fpage>56</fpage>
          . ICDIM, IEEE Computer Society, Washington, DC, USA (
          <year>2018</year>
          ). https://doi.org/10.1109/ICDIM.
          <year>2018</year>
          .8846971
        </mixed-citation>
      </ref>
      <ref id="ref24">
        <mixed-citation>
          24.
          <string-name>
            <surname>Siagian</surname>
            ,
            <given-names>A.H.A.M.</given-names>
          </string-name>
          ,
          <string-name>
            <surname>Aritsugi</surname>
            ,
            <given-names>M.</given-names>
          </string-name>
          :
          <article-title>Robustness of word and character n-grams combinations in detecting deceptive and truthful opinions</article-title>
          .
          <source>J. Data and Information Quality</source>
          (In press). https://doi.org/10.1145/3349536
        </mixed-citation>
      </ref>
      <ref id="ref25">
        <mixed-citation>
          25.
          <string-name>
            <surname>Zaghouani</surname>
            ,
            <given-names>W.</given-names>
          </string-name>
          ,
          <string-name>
            <surname>Char</surname>
            ,
            <given-names>A.</given-names>
          </string-name>
          :
          <article-title>Arap-tweet: A large multi-dialect twitter corpus for gender, age and language variety identi cation</article-title>
          .
          <source>In: Proceedings of the Eleventh International Conference on Language Resources and Evaluation. LREC, European Languages Resources Association (ELRA)</source>
          , Paris, France (
          <year>2018</year>
          ), https://www.aclweb.org/anthology/L18-1111
        </mixed-citation>
      </ref>
      <ref id="ref26">
        <mixed-citation>
          26.
          <string-name>
            <surname>Zaghouani</surname>
            ,
            <given-names>W.</given-names>
          </string-name>
          ,
          <string-name>
            <surname>Char</surname>
            ,
            <given-names>A.</given-names>
          </string-name>
          :
          <article-title>Guidelines and annotation framework for arabic author pro ling</article-title>
          .
          <source>In: Proceedings of the Eleventh International Conference on Language Resources and Evaluation. LREC, European Language Resources Association (ELRA)</source>
          , Paris, France (
          <year>2018</year>
          ), http://lrecconf.org/workshops/lrec2018/W30/pdf/5 W30.pdf
        </mixed-citation>
      </ref>
    </ref-list>
  </back>
</article>