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  <front>
    <journal-meta />
    <article-meta>
      <title-group>
        <article-title>Overview and Results: CL-SciSumm Shared Task 2019</article-title>
      </title-group>
      <contrib-group>
        <contrib contrib-type="author">
          <string-name>Muthu Kumar Chandrasekaran</string-name>
          <email>cmkumar087@gmail.com</email>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Michihiro Yasunaga</string-name>
          <xref ref-type="aff" rid="aff2">2</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Dragomir Radev</string-name>
          <xref ref-type="aff" rid="aff2">2</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Dayne Freitag</string-name>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Min-Yen Kan</string-name>
          <xref ref-type="aff" rid="aff1">1</xref>
        </contrib>
        <aff id="aff0">
          <label>0</label>
          <institution>SRI International</institution>
          ,
          <country country="US">USA</country>
        </aff>
        <aff id="aff1">
          <label>1</label>
          <institution>School of Computing, National University of Singapore</institution>
          ,
          <country country="SG">Singapore</country>
        </aff>
        <aff id="aff2">
          <label>2</label>
          <institution>Yale University</institution>
          ,
          <country country="US">USA</country>
        </aff>
      </contrib-group>
      <fpage>02</fpage>
      <lpage>12</lpage>
      <abstract>
        <p>The CL-SciSumm Shared Task is the rst medium-scale shared task on scienti c document summarization in the computational linguistics (CL) domain. In 2019, it comprised three tasks: (1A) identifying relationships between citing documents and the referred document, (1B) classifying the discourse facets, and (2) generating the abstractive summary. The dataset comprised 40 annotated sets of citing and reference papers of the CL-SciSumm 2018 corpus and 1000 more from the SciSummNet dataset. All papers are from the open access research papers in the CL domain. This overview describes the participation and the o cial results of the CL-SciSumm 2019 Shared Task, organized as a part of the 42nd Annual Conference of the Special Interest Group in Information Retrieval (SIGIR), held in Paris, France in July 2019. We compare the participating systems in terms of two evaluation metrics and discuss the use of ROUGE as an evaluation metric. The annotated dataset used for this shared task and the scripts used for evaluation can be accessed and used by the community at: https://github.com/WING-NUS/scisumm-corpus.</p>
      </abstract>
    </article-meta>
  </front>
  <body>
    <sec id="sec-1">
      <title>-</title>
      <p>
        CL-SciSumm explores summarization of scienti c research in the domain of
computational linguistics research. It encourages the incorporation of new kinds of
information in automatic scienti c paper summarization, such as the facets of
research information being summarized in the research paper. CL-SciSumm also
encourages the use of citing mini-summaries written in other papers, by other
scholars, when they refer to the paper. The Shared Task dataset comprises the
set of citation sentences (i.e., \citances") that reference a speci c paper as a
(community-created) summary of a topic or paper [19]. Citances for a reference
paper are considered a synopses of its key points and also its key contributions
and importance within an academic community [16]. The advantage of using
citances is that they are embedded with meta-commentary and o er a contextual,
interpretative layer to the cited text. Citances o er a view of the cited paper
which could complement the reader's context, possibly as a scholar [
        <xref ref-type="bibr" rid="ref8">8</xref>
        ].
      </p>
      <p>The CL-SciSumm Shared Task is aimed at bringing together the
summarization community to address challenges in scienti c communication
summarization. Over time, we anticipate that the Shared Task will spur the creation of
new resources, tools and evaluation frameworks.</p>
      <p>
        A pilot CL-SciSumm task was conducted at TAC 2014, as part of the larger
BioMedSumm Task4. In 2016, a second CL-Scisumm Shared Task [
        <xref ref-type="bibr" rid="ref6">6</xref>
        ] was held as
part of the Joint Workshop on Bibliometric-enhanced Information Retrieval and
Natural Language Processing for Digital Libraries (BIRNDL) workshop [15] at
the Joint Conference on Digital Libraries (JCDL 2016). This paper provides the
results and insights from CL-SciSumm 2017, which was held as part of
subsequent BIRNDL 2017 workshop[
        <xref ref-type="bibr" rid="ref14">14</xref>
        ] at the annual ACM Conference on Research
and Development in Information Retrieval (SIGIR5).
2
      </p>
    </sec>
    <sec id="sec-2">
      <title>Task</title>
      <p>CL-SciSumm de ned two serially dependent tasks that participants could
attempt, given a canonical training and testing set of papers.</p>
      <p>Given: A topic consists of a Reference Paper (RP) and ten or more Citing
Papers (CPs) that all contain citations to the RP. In each CP, the text spans
(i.e., citances) have been identi ed that pertain to a particular citation to the
RP. Additionally, the dataset provides three types of summaries for each RP:
{ the abstract, written by the authors of the research paper.
{ the community summary, collated from the reference spans of its citances.
{ a human-written summary, written by the annotators of the CL-SciSumm
annotation e ort.</p>
      <p>Task 1A: For each citance, identify the spans of text (cited text spans) in the
RP that most accurately re ect the citance. These are of the granularity of a
sentence fragment, a full sentence, or several consecutive sentences (no more than 5).
Task 1B: For each cited text span, identify what facet of the paper it belongs
to, from a prede ned set of facets.</p>
      <p>Task 2: Finally, generate a structured summary of the RP from the cited text
spans of the RP. The length of the summary should not exceed 250 words. This
was an optional bonus task.
3</p>
    </sec>
    <sec id="sec-3">
      <title>Development</title>
      <p>We built the CL-SciSumm corpus by randomly sampling research papers
(Reference papers, RPs) from the ACL Anthology corpus and then downloading the
4 http://www.nist.gov/tac/2014
5 http://sigir.org/sigir2017/
citing papers (CPs) for those which had at least ten citations. The prepared
dataset then comprised annotated citing sentences for a research paper, mapped
to the sentences in the RP which they referenced. Summaries of the RP were
also included.</p>
      <p>
        The CL-SciSumm 2019 corpus consisted for 40 annotated RPs and their CPs.
These are the same as described in our overview paper in CL-SciSumm 2018 [
        <xref ref-type="bibr" rid="ref7">7</xref>
        ].
The test set was blind. We reused the blind test we used for CL-SciSumm 2018
since we want to have a comparable evaluation CL-SciSumm 2019 systems that
will have additional training data (see Section 3.1).
      </p>
      <p>
        For details of the general procedure followed to construct the CL-SciSumm
corpus, and changes made to the procedure in CL-SciSumm-2016, please see
[
        <xref ref-type="bibr" rid="ref6">6</xref>
        ]. In 2017, we made revisions to the corpus to remove citances from passing
citations. These are described in [
        <xref ref-type="bibr" rid="ref5">5</xref>
        ].
3.1
      </p>
      <p>Annotation
The rst annotated CL-SciSumm corpus was released for The CL-SciSumm 16
shared task. This was annotated based on annotation scheme from what was
followed in previous editions of the task and the original BiomedSumm task
developed by Cohen et. al6: Given each RP and its associated CPs, the annotation
group was instructed to nd citations to the RP in each CP. Speci cally, the
citation text, citation marker, reference text, and discourse facet were identi ed
for each citation of the RP found in the CP.</p>
      <p>Then CL-Scisumm-17 and CL-Scisumm-18 incrementally added more
annotated RPs to its current size of 40 annotated RPs.</p>
      <p>For CL-Scisumm-19, we augment this dataset both Task 1a and Task 2 so
that they have approximately 1000 data points as opposed to 40 in previous
years. Speci cally, for Task 1, we used the method proposed by [17] to prepare
noisy training data for about 1000 unannotated papers. This method involves
automatically matching a citance in a CP with approximately similar reference
spans in its RPs. The number of reference spans per citance is a hyperparameter
that can set as input. For Task 2, we used the SciSummNet corpus proposed
by [23].
4</p>
    </sec>
    <sec id="sec-4">
      <title>Overview of Approaches</title>
      <p>Nine systems out of the seventeen registered systems { in Task 1 and a subset of
ve also participated in Task 2 { submitted their output for evaluation. We
include these system papers in the BIRNDL 2019 proceedings. We will now brie y
summarise their methods and key results in lexicographic order by team name.</p>
      <p>
        System 1 is from Nanjing University of Science and Technology [
        <xref ref-type="bibr" rid="ref13">13</xref>
        ]. For
Task 1A, they use multi-classi ers and integrate their results via voting system.
      </p>
      <sec id="sec-4-1">
        <title>6 http://www.nist.gov/tac/2014</title>
        <p>Compared with previous work, this year they make new selection of features
based on correlation analysis, apply similarity-based negative sampling strategy
when creating training dataset and add deep learning models for classi cations.
For Task 1B, they rstly calculate the probability that each word would belong
to the speci c facet based on training corpus and then some prior rules are
added to obtain nal result. For Task 2, to obtain a logical summary, they group
sentences in two ways, rst based on their relevance between abstract segments
and second arranged by recognized facet from task 1B. Then they pick out
important sentences via ranking.</p>
        <p>
          System 2 is from Beijing University of Posts and Telecommunications (BUPT)
[
          <xref ref-type="bibr" rid="ref10">10</xref>
          ]. They build a new feature of Word2vec H for the CNN model to calculate
sentence similarity for citation linkage. In addition to the methods used last
year, they also intend to apply CNN for facet classi cation. In order to improve
the performance of summarization, they develop more semantic representations
for sentences based on neural network language models to construct new kernel
matrix used in Determinantal Point Processes (DPPs).
        </p>
        <p>System 3 is from University of Manchester [24]. For Task 1 they looked into
supervised and semi-supervised approaches. They explored the potential of
netuning bidirectional transformers for the identi cation of cited passages. They
further formalised the task as a similarity ranking problem and implemented
bilateral multi-perspective matching for natural language sentences. For Task 2,
they used hybrid summarisation methods to create a summary from the content
of the paper and the cited text spans.</p>
        <p>System 4 is from University of Toulouse [18]. They focus on Task 1A.
They rst identify candidate sentences in the reference paper and compute their
similarities to the citing sentence using tf-idf and embedding-based methods as
well as other features such as POS tags. They submitted 15 runs with di erent
con gurations.</p>
        <p>System 7 is from IIIT Hyderabad and Adobe Research [21]. Their
architecture incorporates transfer learning by utilising a combination of pretrained
embeddings which are subsequently used for building models for the given tasks.
In particular, for task 1A, they locate the related text spans referred to by the
citation text by creating paired text representations and employ pre-trained
embedding mechanisms in conjunction with XGBoost, a gradient boosted decision
tree algorithm to identify textual entailment. For task 1B, they make use of
the same pretrained embeddings and use the RAKEL algorithm for multi-label
classi cation.</p>
        <p>
          System 8 is from Universitat Pompeu Fabra and Universidad de la
Republica [
          <xref ref-type="bibr" rid="ref2">2</xref>
          ]. They propose a supervised system based on recurrent neural networks
and an unsupervised system based on sentence similarity for Task 1A, one
supervised approach for Task 1B, and one supervised approach for Task 2. The
approach for Task 2 follows the method by the winning approach in CL-SciSumm
2018.
        </p>
        <p>System 9 is from Politecnico di Torino [20]. Their approach to tasks 1A
and 1B relies on an ensemble of classi cation and regression models trained on
the annotated pairs of cited and citing sentences. Facet assignment is based on
the relative positions of the cited sentences locally to the corresponding section
and globally in the entire paper. Task 2 is addressed by predicting the overlap
(in terms of units of text) between the selected text spans and the summary
generated by the domain experts. The output summary consists of the subset of
sentences maximizing the predicted overlap score.</p>
        <p>
          System 12 is from Nanjing University and Kim Il Sung University [
          <xref ref-type="bibr" rid="ref9">9</xref>
          ].
They propose a novel listwise ranking method for cited text identi cation. Their
method have two stages: similarity-based ranking and supervised listwise
ranking. In the rst stage, we select the top-5 sentences per a citation text, due to
the modi ed Jaccard similarity. These top-5 selected sentences are proceeded to
rank by a CitedListNet (listwise ranking model based on deep learning). They
select 36 similarity features and 11 section information as feature. Finally, they
select two sentences on the sentence list ranked by CitedList- Net.
        </p>
        <p>
          System 17 is from National Technical University of Athens, Athens
University of Economics and Business, and Athena Research and Innovation Center [
          <xref ref-type="bibr" rid="ref4">4</xref>
          ].
Their approach is twofold. Firstly they classify sentences of an abstract to
prede ned classes called \zones". They use sentences from selected zones to nd the
most similar ones of the rest sentences of the paper which constitute the
\candidate sentences". Secondly, they employ a siamese bi-directional GRU neural
network with a logistic regression layer to classify if a citation sentence cites a
candidate sentence.
5
        </p>
      </sec>
    </sec>
    <sec id="sec-5">
      <title>Evaluation</title>
      <p>An automatic evaluation script was used to measure system performance for
Task 1A, in terms of the sentence ID overlaps between the sentences identi ed
in system output, versus the gold standard created by human annotators. The
raw number of overlapping sentences were used to calculate the precision, recall
and F1 score for each system. We followed the approach in most SemEval tasks
in reporting the overall system performance as its micro-averaged performance
over all topics in the blind test set.</p>
      <p>
        Additionally, we calculated lexical overlaps in terms of the ROUGE-2 and
ROUGE-SU4 scores [
        <xref ref-type="bibr" rid="ref11">11</xref>
        ] between the system output and the human annotated
gold standard reference spans.
      </p>
      <p>
        We have been reporting ROUGE scoring since CL-SciSumm 17, for Tasks 1a
and Task 2. Recall-Oriented Understudy for Gisting Evaluation (ROUGE) is
a set of metrics used to automatically evaluate summarization systems [
        <xref ref-type="bibr" rid="ref11">11</xref>
        ]
by measuring the overlap between computer-generated summaries and
multiple human written reference summaries. In previous studies, ROUGE scores
have signi cantly correlated with human judgments on summary quality [
        <xref ref-type="bibr" rid="ref12">12</xref>
        ].
Di erent variants of ROUGE di er according to the granularity at which
overlap is calculated. For instance, ROUGE{2 measures the bigram overlap between
the candidate computer-generated summary and the reference summaries. More
generally, ROUGE{N measures the n-gram overlap. ROUGE{L measures the
overlap in Longest Common Subsequence (LCS). ROUGE{S measures
overlaps in skip-bigrams or bigrams with arbitrary gaps in-between. ROUGE-SU
uses skip-bigram plus unigram overlaps. CL-SciSumm 2017 uses ROUGE-2 and
ROUGE-SU4 for its evaluation.
      </p>
      <p>Task 1B was evaluated as a proportion of the correctly classi ed discourse
facets by the system, contingent on the expected response of Task 1A. As it is a
multi-label classi cation, this task was also scored based on the precision, recall
and F1 scores.</p>
      <p>Task 2 was optional, and also evaluated using the ROUGE{2 and ROUGE{
SU4 scores between the system output and three types of gold standard
summaries of the research paper: the reference paper's abstract, a community
summary, and a human summary.</p>
      <p>The evaluation scripts have been provided at the CL-SciSumm Github
repository7 where the participants may run their own evaluation and report the results.
6</p>
    </sec>
    <sec id="sec-6">
      <title>Results</title>
      <p>This section compares the participating systems in terms of their performance.
Five of the nine system that did Task 1 also did the bonus Task 2. Following
are the plots with their performance measured by ROUGE{2 and ROUGE{SU4
against the 3 gold standard summary types. The results are provided in Table 1
and Figure 1. The detailed implementation of the individual runs are described
in the system papers included in this proceedings volume.</p>
      <p>
        For Task 1A, the best performance was shown by System 3 (Team UoM) [24].
Their performance was closely followed by System 12 [
        <xref ref-type="bibr" rid="ref9">9</xref>
        ]. Both teams
implemented deep learning-based systems. One of the key goals of CL-SciSumm '19
was to boost performance of deep learning models by adding more training data.
It is encouraging though not surprising to see the best performance from deep
learning models. The third best system was system 2 (Team CIST-BUPT) which
was also the best performer for Task 1B, the classi cation task. Second best
performance Task 1B was by System 4 (Team IRIT-IRIS).
      </p>
      <p>On the summarisation task, Task 2, System 3 (Team UoM) had the best
performance against the abstract. System 2 (Team CIST-BUPT) had the best
performance for community and human summaries. Again, both are deep
learningbased systems. The additional 1000 summaries from SciSummnet as training
data has resulted in the improved performance. System 2 was the second against
abstract summaries, and system 3 was the second against human summaries.
7</p>
    </sec>
    <sec id="sec-7">
      <title>Research questions and discussions</title>
      <p>For CL-SciSumm '19, we augmented the CL-SciSumm '18 training datasets for
both Task 1a and Task 2 so that they have approximately 1000 data points as</p>
      <sec id="sec-7-1">
        <title>7 github.com/WING-NUS/scisumm-corpus</title>
        <p>Vs. Abstract</p>
        <p>RSU{4
system 12 Run 2 0.266
system 12 Run 3 0.286
system 12 Run 4 0.315
system 17 ntua-ilsp-RUN_NN0.F013
system 17 ntua-ilsp-RUN-NN0T.016
system 2 run1-Jaccard-Casc0a.d2e7-4Voting-LSA_method_3
system 2 run10-Jaccard-Foc0u.s2e9d4-Voting-LSA_method_4
system 2 run11-Jaccard-Foc0u.s2e9d4-Voting-QD_method_1
system 2 run12-Jaccard-Foc0u.s2e9d4-Voting-SentenceVec_method_2
system 2 run13-Voting-1.1-S0u.b3t8it9leAndHfw-LSA_method_3
system 2 run14-Voting-1.1-S0u.b3t8it9leAndHfw-LSA_method_4
system 2 run15-Voting-1.1-S0u.b3t8it9leAndHfw-QD_method_1
system 2 run16-Voting-1.1-S0u.b3t8it9leAndHfw-SentenceVec_method_2
system 2 run17-Voting-2.0-T0e.x3t4C2NN-LSA_method_3
system 2 run18-Voting-2.0-T0e.x3t4C2NN-LSA_method_4
system 2 run19-Voting-2.0-T0e.x3t4C2NN-QD_method_1
system 2 run2-Jaccard-Casc0a.d2e7-4Voting-LSA_method_4
system 2 run20-Voting-2.0-T0e.x3t4C2NN-SentenceVec_method_2
system 2 run21-Voting-2.0-V0o.t3in4g1-LSA_method_3
system 2 run22-Voting-2.0-V0o.t3in4g1-LSA_method_4
Fig. 1: Performances on (a) Task 1A in terms of sentence overlap and
ROUGESU4, and (b) Task 1B conditional on Task 1A
Human R-2</p>
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ystem 1 Run 21
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ystem 1 Run 2
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ystem 1 Run 23
system 1 Run 275
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ystem 1 Run 25
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system 1 Run 328
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        <p>o ing-2.0-V0o.t2in5
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nte run i
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seynstetenmce2Vreucn_2m6e-Wthordd_22v_ehacHub-0H-sm.C0t2-ra.Ca2nc1N2t2N-S-uSbutbitlietlAenAdn0Hd.01Hf.3w1f5w3-SentenceVec_method_2_haubsmtraanct</p>
        <p>Fig. 2: Task 2 Performances on (a) Abstract, (b) Community and (c) Human
maries. Plots correspond to the numbers in Table 2.
opposed to 40 in previous years. Speci cally, for Task 1, we used the method
proposed by [17] to prepare noisy training data for about 1000 unannotated
papers; for Task 2, we used the SciSummNet corpus proposed by [23]. For
CLSciSumm '19 we use the same blind test data used in CL-SciSumm '18.</p>
        <p>
          Based on this we propose the following research questions to comparatively
analyse results from CL-SciSumm '18 with those from CL-SciSumm '19. The
research questions we have are:
RQ1. Did data augmentation help systems achieve better performance?
The best Task 1a performance (sentence overlap F1) this year is 0.126 from
System 3 [24] which is a deep learning system trained on augmented data. This
is about 0.02 lower than the best CL-SciSumm'18 system [22] which was at 0.145.
It appears that the data augmentation has helped deep learning methods. The
only fully deep learning system from CL-SciSumm '18 [
          <xref ref-type="bibr" rid="ref3">3</xref>
          ] achieved 0.044. So,
increasing training data is clearly the way forward. Traditional machine learning
based systems such as [
          <xref ref-type="bibr" rid="ref10">10</xref>
          ] seem to su er from noise in the augmented data. We
propose to use better data generation method that produces data cleaner than
the naive similarity based cut-o method [17] used this time.
        </p>
        <p>Note that there was no data augmentation to Task 1b. So, the performance
of traditional methods across CL-SciSumm '18 and CL-SciSumm, '19 are largely
the same.</p>
        <p>
          The best on CL-SciSumm '19 Task 2 performance on human written
summaries on ROUGE-2 is 0.278 by [
          <xref ref-type="bibr" rid="ref10">10</xref>
          ]. This is higher than the best CL-SciSumm'18
system which score 0.252 [
          <xref ref-type="bibr" rid="ref1">1</xref>
          ]. This suggests that the additional 1000 ScisummNet
summaries is useful to further performance. It also indicates that SciSummNet
relatively cleaner than the auto annotated data used for Task 1a.
        </p>
        <p>RQ2. CL-SciSumm '19 encouraged participants to use deep learning based
methods; do they perform better than traditional machine learning methods?
In Task 1a the best performing CL-SciSumm '19 system The best performing
CL-SciSumm '18 system [22] used traditional models including random forests
and ranking models trained on the CL-SciSumm '18 training data. This implies
that for Task 1a, traditional models trained on clean data perform better than
deep learning models trained on noisy data. However, if we look at CL-SciSumm
'19 systems' performances, we notice that deep learning models perform better
than traditional machine learning models when trained on the augmented data.</p>
        <p>On Task 1b, systems using traditional methods perform better than deep
learning systems. Note that the winner for Task 1a, System 3, is not the best
system for Task 1b although they are not far behind. We also did not add any
additional training data to Task 1b. So, we cannot rule out that deep
learning systems will not perform better than traditional methods when trained on
enough data.</p>
        <p>On Task 2, the best performing system on human summaries, System 2, using
neural representations trained on the 1000 plus summaries, does the best with a
ROUGE-2 score of 0.278. This is higher than CL-SciSumm '18 top system using
traditional methods. System 3, the second best Cl-SciSumm '19 system an
endend deep learning model, with a score of 0.265 is also higher than CLSciSumm
'18 top system. With a score of 0.514 System 3 also improves the state-of-the-art
agasint abstracts by 0.2 on ROUGE-2 score. System 3 is also the top system on
community summaries with a ROUGE-2 score of 0.204.</p>
        <p>In summary, deep learning models do well across the board for summaries.
Traditional methods do better on Task 1a on small but clean training data. Deep
learning methods take over on large bu tnoisy data.
8</p>
      </sec>
    </sec>
    <sec id="sec-8">
      <title>Conclusion</title>
      <p>Nine systems participated in CL-SciSumm 2019 shared tasks. The systems were
provided with larger but noisy corpus with automatic annotation. Nearly all the
teams had neural methods and many employed transfer learning. Participants
also experimented with the use of word embeddings trained on the shared task
corpus, as well as on other domain corpora. We found that data augmentation
for Task 1a may have helped deep learning models but not traditional machine
learning methods. It also appears that deep learning methods perform better
than traditional methods across the board when they have enough training data.
We will explore methods to obtain cleaner training data for Task 1 without or
with minimal human annotation e ort.</p>
      <p>We recommend that future approaches should go beyond o -the-shelf deep
learning methods, and also exploit the structural and semantic characteristics
that are unique to scienti c documents; perhaps as an enrichment device for word
embeddings. The committee also observes that CL-SciSumm series over the past
5 years has catalysed research in the area of scienti c document summarisation.
We observe that a number of papers outside of the BIRNDL workshop published
at prominent NLP and IR venues evaluate on the CL-SciSumm gold standard
data. To create a reference corpus for the task was a key goal of the series.
We have achieved this goal now. We will consider newer tasks to push the e ort
towards automated literature reviews. We will also consider switching the format
of the shared evaluation from a shared task to a leaderboard to which systems
can submit evaluations asynchronously throughout the year.</p>
      <p>Acknowledgement. We would like to thank SRI International for their
generous funding of CL-SciSumm '19 and BIRNDL '19. We thank
ChanZuckerberg Initiative for sponsoring the invited talk. We would also like
to thank Vasudeva Varma and colleagues at IIIT-Hyderabad, India and
University of Hyderabad for their e orts in convening and organizing our
annotation workshops in 2016-17. We acknowledge the continued advice
of Hoa Dang, Lucy Vanderwende and Anita de Waard from the pilot
stage of this task. We would also like to thank Rahul Jha and Dragomir
Radev for sharing their software to prepare the XML versions of papers.
We are grateful to Kevin B. Cohen and colleagues for their support, and
for sharing their annotation schema, export scripts and the Knowtator
package implementation on the Protege software { all of which have been
indispensable for this shared task.
Retrieval and Natural Language Processing for Digital Libraries (BIRNDL
2017) co-located with the 40th International ACM SIGIR Conference on
Research and Development in Information Retrieval (SIGIR 2017), Tokyo,
Japan, August 11, 2017. pp. 1{6 (2017), http://ceur-ws.org/Vol-1888/
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</article>