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    <journal-meta />
    <article-meta>
      <title-group>
        <article-title>Overview of the Causality-driven Adhoc Information Retrieval (CAIR) task at FIRE-2021</article-title>
      </title-group>
      <contrib-group>
        <contrib contrib-type="author">
          <string-name>Suchana Datta</string-name>
          <xref ref-type="aff" rid="aff1">1</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Debasis Ganguly</string-name>
          <xref ref-type="aff" rid="aff2">2</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Dwaipayan Roy</string-name>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Derek Greene</string-name>
          <xref ref-type="aff" rid="aff1">1</xref>
        </contrib>
        <aff id="aff0">
          <label>0</label>
          <institution>Indian Institute of Science Education and Research</institution>
          ,
          <addr-line>Kolkata</addr-line>
        </aff>
        <aff id="aff1">
          <label>1</label>
          <institution>University College Dublin</institution>
          ,
          <country country="IE">Ireland</country>
        </aff>
        <aff id="aff2">
          <label>2</label>
          <institution>University of Glasgow</institution>
          ,
          <country country="UK">United Kingdom</country>
        </aff>
      </contrib-group>
      <abstract>
        <p>The CAusality-based Information Retrieval (CAIR) track at FIRE 2021 focuses on the task of retrieving potentially relevant documents in response to a query indicating one or more events, where the notion of relevance is determined by whether a document indicates potential causes that might have led to the specified events in the query. In 2020, we released a dataset comprised of a benchmark set of 25 queries along with the relevance judgments. The target document collection is the English monolingual FIRE ad-hoc document collection. This second iteration of the track acted as a continuation of the same task with the same dataset as in the last year. The objective was to encourage the participants to try out more involved approaches (e.g. supervised ones) for improving on the retrieval efectiveness.</p>
      </abstract>
      <kwd-group>
        <kwd>eol&gt;Causal Information Retrieval</kwd>
        <kwd>Semantic Search</kwd>
        <kwd>BERT</kwd>
        <kwd>Apache Nutch</kwd>
      </kwd-group>
    </article-meta>
  </front>
  <body>
    <sec id="sec-1">
      <title>1. Introduction</title>
      <p>
        In traditional ad-hoc IR setup, a search system retrieves a ranked list of documents given a query.
The usefulness of the output of an ad-hoc IR system, in the form of a ranked list of documents,
is limited in situations when i) decision makers need to formulate policies to mitigate a current
event that requires attention (e.g. drop in the value of British pound), or ii) policy-making
regarding societal benefits (e.g. formulating government policies to reduce housing crisis by
analyzing the main likely causes). In the aforementioned situations, a traditional search system
user is required to carefully analyze the topically relevant documents (likely to describe the
main event expressed in the query itself) and most likely needs to reformulate queries in order
to retrieve documents related to the potential causes leading to the (query) event. The user of
a traditional IR system, hence, needs to spend considerable efort in reformulating queries in
order to retrieve the causally relevant documents towards top ranks [
        <xref ref-type="bibr" rid="ref1 ref2">1, 2</xref>
        ].
      </p>
      <p>
        With this motivation, we proposed a shared task for the first time in FIRE 2020 [ 3] to
investigate approaches to reduce this manual efort and ask participants to design efective
retrieval models seeking to address causality-based relevance [
        <xref ref-type="bibr" rid="ref1 ref2">1, 2</xref>
        ] rather than the traditional
topical relevance.
      </p>
      <p>We provided participants a static test collection of 303, 291 news documents and a list of 25
queries, divided into two parts - 5 queries for training and 20 queries for test, related to events
that were likely to be caused by a number of other past events. We also provided associated
relevance judgements for the set of train queries. The participants were to required to develop
ranking models that could efectively retrieve documents containing information on such past
events which were likely candidates to lead to the query event.</p>
      <p>From the first iteration of CAIR track [ 3], the two main observations were that, firstly, longer
queries showed a general trend to yield more causally relevant documents towards top ranks as
seen from the results obtained from the first participating group [ 4]; and secondly, it also turned
out that sequence-based text representation for semantically matching the documents with
queries did not yield efective retrieval results [ 5] and thus leaving open a scope to apply more
involved approaches for addressing the task of causality-based retrieval. With this motivation,
we have continued the second iteration of CAIR task at FIRE 20211.</p>
    </sec>
    <sec id="sec-2">
      <title>2. Dataset</title>
      <p>As the notion of causality difers from the idea of topical relevance, the selection of topics for
this task was restricted to the query events with causal information need as we detailed in [3].
In this section, we briefly recapitulate the dataset construction process.</p>
      <p>Target Collection The second iteration of the track uses the same target collection as in the
ifrst year [ 3], i.e., the English ad-hoc IR collection of FIRE [6]. The news articles were crawled
from the source ‘Telegraph India’2 published over a period of 10 years (2001 to 2011) [3].
Query Formulation This year the task was run with same query set as in 2020. As mentioned
in [3], while selecting the topics, we took the following into consideration.</p>
      <p>1. We ensured that a query is representative of an event that occurred during the period
covered by the target collection, i.e. between 2001-2011.
2. An event qualifies as a valid topic only if there exists a multiple number of potential
(arguable) causes that might have led to it. We eliminate those cases where the notion of
causality is mentioned in the same document also describing the query event or it does
not help user to walk through the chain of query event at all.</p>
      <p>Relevance Assessments In contast to the previous year, where we extended the judgment
pool with new documents obtained from the runs submitted by participating teams, this year we
did not extend the relevance pool. This means that the relevance assessments are also identical
to what was used in CAIR 2020 [3].</p>
      <sec id="sec-2-1">
        <title>1http://fire.irsi.res.in/fire/2021/home 2https://www.telegraphindia.com/</title>
      </sec>
    </sec>
    <sec id="sec-3">
      <title>3. Models Proposed by Participating Teams</title>
      <p>We received a total of four submissions from two participating teams this year. The proposed
model architectures are as follows:
NUIG [7] This team is comprised of participants both from National University of Ireland and
University College Cork. The team proposed a semantic search pipeline that aggregates results
across multiple query strategies and indices (a lexical and a semantic index). The authors applied
three query strategies, denoted as 1, 2, and 3, where, 1 embeds the query using the
sentence embedding model and retrieves the most relevant results based on cosine similarity; 2
and 3 retrieve the most relevant documents from the lexical index. Finally, 3 adds filtering
and keyword extraction steps to transform the narrative description in causal search terms.
In the end, results from all three queries (1, 2, and 3 respectively) are aggregated and
re-ranked by the aggregating module.</p>
      <p>NITS [8] Team ‘NITS’ is from National Institute of Technology, Silchar. They investigated
the potential of neural network-based language representation models, specifically the BERT
model [9] and Apache Nutch [10] for the task of causal documents retrieval. The BERT model
transformed the sequence of words into fixed-size embedding vector and used cosine similarity
for relevance measurement; whereas, Apache Nutch is a keyword matching approach and
used an AND search module to retrieve news articles that match to the input query. However,
the results showed that sequence-based text representation for semantically matching the
documents with queries did not yield efective retrieval results.</p>
    </sec>
    <sec id="sec-4">
      <title>4. Evaluation</title>
      <p>Each participating team was allowed to submit at most three runs. Team NUIG has submitted
single run while three runs were submitted by team NITS. We evaluate each submitted run
based on their performance achieved over 20 test queries. In particular, we used the following
evaluating measures to report model’s eficiency:
– MAP: We chose Mean Average Precision (MAP) as our primary measure of retrieval
efectiveness so as to take both precision and recall into account. This metric quantifies
the retrieval model based on the mean of the average precision scores achieved per query.
– P@5: We also made use of  @5 to measure model’s eficacy, i.e. number of relevant
documents present in the top 5 ranked documents and averaged over test query set.
The performances are evaluated using ‘trec-eval’ 3 and the results are reported in Table 1.</p>
    </sec>
    <sec id="sec-5">
      <title>5. Results</title>
      <sec id="sec-5-1">
        <title>3https://trec.nist.gov/trec eval/</title>
        <p>
          Followings are the few observations that we made from this year submissions (see Table 1) :
• The best results this year are better than the results from 2020 [3]. It is worth mentioning
that the results are comparable across the two versions of the track, because the dataset
is identical.
• NUIG’s supervised approach [7], pairwise training of causality specific similarity,
outperforms an unsupervised approach [8].
• As claimed by authors in [
          <xref ref-type="bibr" rid="ref1">1</xref>
          ] which proposes an unsupervised technique, causally
connected documents are likely to have only a partial term overlap with the corresponding
topical set, query narrations are certainly a good resource of finding such causality specific
terms given the query event. However, it turned out that retrieving only with titles is
better than also making use of the narratives.
• Supervised approach turned out to be better than query enrichment methods of the last
year.
        </p>
        <p>Year
2021
2020</p>
        <p>Team
NUIG
NITS
UCSC
NITS</p>
        <p>Run ID</p>
        <p>MAP
BERT()
BERT()
Nutch()


post-event
-terms-expan
[3] S. Datta, D. Ganguly, D. Roy, D. Greene, C. Jochim, F. Bonin, Overview of the
causalitydriven adhoc information retrieval (CAIR) task at FIRE-2020, in: FIRE 2020: Forum for
Information Retrieval Evaluation, Hyderabad, India, December 16-20, 2020, ACM, 2020, pp.
14–17.
[4] C. Lin, Y. Zhang, Causality detection for causality-driven adhoc information retrieval task,
in: Proceedings of FIRE 2020 - Forum for Information Retrieval Evaluation (December
2020), 2020.
[5] P. Dadure, P. Pakray, S. Bandyopadhyay, Preliminary investigation on causality information
retrieval, in: Proceedings of FIRE 2020 - Forum for Information Retrieval Evaluation
(December 2020), 2020.
[6] S. Palchowdhury, P. Majumder, D. Pal, A. Bandyopadhyay, M. Mitra, Overview of FIRE
2011, in: Multilingual Information Access in South Asian Languages - Second International
Workshop, FIRE 2010, Gandhinagar, India, February 19-21, 2010 and Third International
Workshop, FIRE 2011, Bombay, India, December 2-4, 2011, Revised Selected Papers, 2011,
pp. 1–12.
[7] D. Dalal, S. D. Gupta, B. Binaei, A semantic search pipeline for causality-driven adhoc
information retrieval, in: Proceedings of FIRE 2021 - Forum for Information Retrieval
Evaluation (December 2021), 2021.
[8] P. Dadure, P. Pakray, S. Bandyopadhyay, Causal document retrieval using bert and
apache nutch, in: Proceedings of FIRE 2021 - Forum for Information Retrieval Evaluation
(December 2021), 2021.
[9] J. Devlin, M. Chang, K. Lee, K. Toutanova, Bert: Pre-training of deep bidirectional
transformers for language understanding, 2019. arXiv:1810.04805.
[10] R. Khare, R. C. Douglas, K. Sitaker, A. Rifkin, Nutch: A flexible and scalable open-source
web search engine, 2005.
[11] D. Cer, Y. Yang, S. Kong, N. Hua, N. Limtiaco, R. S. John, N. Constant, M.
GuajardoCespedes, S. Yuan, C. Tar, Y. Sung, B. Strope, R. Kurzweil, Universal sentence encoder,
2018. arXiv:1803.11175.</p>
      </sec>
    </sec>
  </body>
  <back>
    <ref-list>
      <ref id="ref1">
        <mixed-citation>
          [1]
          <string-name>
            <given-names>S.</given-names>
            <surname>Datta</surname>
          </string-name>
          ,
          <string-name>
            <given-names>D.</given-names>
            <surname>Ganguly</surname>
          </string-name>
          ,
          <string-name>
            <given-names>D.</given-names>
            <surname>Roy</surname>
          </string-name>
          ,
          <string-name>
            <given-names>F.</given-names>
            <surname>Bonin</surname>
          </string-name>
          ,
          <string-name>
            <given-names>C.</given-names>
            <surname>Jochim</surname>
          </string-name>
          ,
          <string-name>
            <given-names>M.</given-names>
            <surname>Mitra</surname>
          </string-name>
          ,
          <article-title>Retrieving potential causes from a query event</article-title>
          ,
          <source>in: Proceedings of the 43rd International ACM SIGIR Conference on Research and Development in Information Retrieval</source>
          , SIGIR '20,
          <string-name>
            <surname>Association</surname>
          </string-name>
          for Computing Machinery,
          <year>2020</year>
          , p.
          <fpage>1689</fpage>
          -
          <lpage>1692</lpage>
          .
        </mixed-citation>
      </ref>
      <ref id="ref2">
        <mixed-citation>
          [2]
          <string-name>
            <given-names>S.</given-names>
            <surname>Datta</surname>
          </string-name>
          ,
          <string-name>
            <given-names>D.</given-names>
            <surname>Greene</surname>
          </string-name>
          ,
          <string-name>
            <given-names>D.</given-names>
            <surname>Ganguly</surname>
          </string-name>
          ,
          <string-name>
            <given-names>D.</given-names>
            <surname>Roy</surname>
          </string-name>
          ,
          <string-name>
            <given-names>M.</given-names>
            <surname>Mitra</surname>
          </string-name>
          ,
          <article-title>Where's the why? in search of chains of causes for query events</article-title>
          ,
          <source>in: Proceedings of The 28th Irish Conference on Artificial Intelligence and Cognitive Science</source>
          , Dublin, Republic of Ireland, December 7-
          <issue>8</issue>
          ,
          <year>2020</year>
          , volume
          <volume>2771</volume>
          <source>of CEUR Workshop Proceedings, CEUR-WS.org</source>
          ,
          <year>2020</year>
          , pp.
          <fpage>109</fpage>
          -
          <lpage>120</lpage>
          .
        </mixed-citation>
      </ref>
    </ref-list>
  </back>
</article>