=Paper= {{Paper |id=Vol-3671/paper9 |storemode=property |title=Event Extraction Alone Is Not Enough |pdfUrl=https://ceur-ws.org/Vol-3671/paper9.pdf |volume=Vol-3671 |authors=Junbo Huang,Longquan Jiang,Cedric Moeller,Ricardo Usbeck |dblpUrl=https://dblp.org/rec/conf/ecir/Huang0MU24 }} ==Event Extraction Alone Is Not Enough== https://ceur-ws.org/Vol-3671/paper9.pdf
                                Event Extraction Alone Is Not Enough
                                Junbo Huang1,∗ , Longquan Jiang1 , Cedric Möller1 and Ricardo Usbeck2,∗
                                1
                                    University of Hamburg, Department of Computer Science, Vogt-Kölln-Straße 30, 22527 Hamburg, Germany
                                2
                                    Leuphana University Lüneburg, Universitätsallee 1, 21335 Lüneburg, Germany


                                              Abstract
                                              With the growing amount of online data, distinguishing between similar events and news about them
                                              poses a significant challenge for both companies and crisis reaction units. To discriminate event instances,
                                              we present Eventist, a silver-standard event instance dataset from news in English, containing 23,304
                                              news headlines from 90 countries covering in total 113 storm-related events between 1𝑠𝑡 January 2021
                                              and 1𝑠𝑡 September 2023. Sampled data is validated by two human raters. Additionally, we propose to
                                              adopt a sentence-level event representation for modeling media narrative discourse. Finally, we provide
                                              two pairwise comparison benchmarks on event deduplication and event temporal ordering, enabling the
                                              practicality of event extraction.

                                              Keywords
                                              Event Deduplication, Event Temporal Ordering, Media Narrative Discourse




                                1. Introduction
                                With climate change, a noticeable uptick in the frequency and severity of tropical storms and
                                their associated impacts is observed [1, 2]. Notably, storm surges, including extreme floods and
                                tsunamis, often result in more significant damage than the storms themselves. To automatically
                                identify storm events holds the potential for fast crisis responses. Consequently, event extraction
                                from media texts has emerged as a pivotal task in Natural Language Processing (NLP) [3, 4].
                                   We view media texts as narratives describing specific events with their often implicit causal
                                or temporal relations. We address news headlines as compressed narratives containing partial
                                event information. An event, in this context, denotes the real-world occurrence of a particular
                                incident, attributed to its constituent elements such as participants, temporal attributes, and
                                geographical location, often resulting in a change of state of a set of geopolitical entities (GPEs)
                                [5]. In this study, we represent events with English-language news headlines, with a focus
                                on storm-related narratives. Specifically, storm-related narratives are texts with at least one
                                storm-related event mention.
                                   In NLP, events are referred to as word-based event mentions, typically represented as verbs
                                or nouns [3, 4, 6]. For instance, in the headline “Latest from the Tropics: Tropical Storm Bret

                                In: R. Campos, A. Jorge, A. Jatowt, S. Bhatia, M. Litvak (eds.): Proceedings of the Text2Story’24 Workshop, Glasgow
                                (Scotland), 24-March-2024
                                ∗
                                    Corresponding author.
                                Envelope-Open junbo.huang@uni-hamburg.de (J. Huang); longquan.jiang@uni-hamburg.de (L. Jiang);
                                cedric.möller@uni-hamburg.de (C. Möller); ricardo.usbeck@leuphana.de (R. Usbeck)
                                Orcid 0000-0002-3192-5896 (J. Huang); 0000-0002-7333-2589 (L. Jiang); 0000-0001-6700-3482 (C. Möller);
                                0000-0002-0191-7211 (R. Usbeck)
                                            © 2024 Copyright for this paper by its authors. Use permitted under Creative Commons License Attribution 4.0 International (CC BY 4.0).




CEUR
                  ceur-ws.org
Workshop      ISSN 1613-0073
Proceedings

                                                                                                             105
 (a) Event distribution over temporally overlapping (b) Sentence-level event representation on 2023 Cy-
     events. Note that multiple events can have a       clone Gabrielle in different stages of event de-
     compound effect on a set of geopolitical entities. velopment. This representation captures event
     Such compound effect can not be captured by        attributes, the effect of events and the telling of
     extracting only word-based event mentions.         the events, known as narrative discourse.

Figure 1: Distribution of Events and Illustration on Different Media Narratives Overtime


weakens while Cindy strengthens”, the extracted word-based event mentions are “Tropical
Storm Bret” (formed on June 19, 2023) and “Cindy” (formed on June 27, 2023). We argue for
the significance of recognizing narrative discourses involves nuances in news storytelling. In
this example, the narrative’s temporal focus shifts from the decline of tropical storm Bret to
the emergence of tropical storm Cindy. We consider the self-referential change of state, of one
being weakened and another being strengthened, as the effect of an event, represented by a
single news headline containing two word-based event mentions.
   A significant yet often overlooked challenge lies in determining whether different news
articles pertain to the same event. Discrepancies between word-based event mentions and
events present a formidable obstacle known as event instance discrimination [7, 8, 9]. Despite
its critical importance, there exists no standardized benchmark or task formulation to address
this issue. Prior attempts have involved entity matching based on factors such as location and
time [7, 8, 10], or linking event mentions to entries in a knowledge graph (KG) like Wikidata
[9]. However, heuristic-driven methods often suffer from poor generalization, while KG-driven
approaches are limited by the inability to represent events absent from the KG. More importantly,
extracting only word-based event mentions fails to represent the effect of events.
   Furthermore, annotating mentions at the word level is a costly process, often resulting in low
agreement among annotators [11, 12, 13]. Evidence suggests that word-based event mentions
are not crucial for effective event detection [14, 15]. In our approach, we utilize sentence-level
event representation, as illustrated in Figure 1b. Sentence-level event representation can better
capture (1) event attributes, (2) the effect of events, and (3) the telling of the events, also known
as narrative discourse [16]. Narrative discourse varies before, during, and after the event, which
is practically important in many disciplines [3, 4, 17, 18].
   To achieve this goal of distinguishing event instances in news streams (Figure 1a), drawing
inspiration from the success of deep distance metric learning [19, 20], we suggest a baseline




                                                  106
system for two pairwise comparison tasks. Our contributions include:
    • Introducing a large-scale silver-standard event instance dataset named Eventist. The
      dataset comprises 23,304 English news headlines, covering a total of 113 storm-related
      real-world events from 90 countries between January 1, 2021, and September 1, 2023.
    • Providing two benchmarks on event deduplication and event temporal ordering. We have
      made the dataset, baseline models, and code openly accessible on https://github.com/
      semantic-systems/paper-event-instance-discrimination.


2. Related Work
Dataset To our knowledge, the most closely related dataset concerning crisis-related news
articles linked to KGs is Crisisfacts [4], initially designed for extracting atomic facts for temporal
summarization. Events are linked to Wikidata, and publication dates are available as meta-
information. It is theoretically possible to re-formulate the temporal summarization task into
event deduplication and event temporal ordering. However, as depicted in Table 1, Crisisfacts
encompasses only 8 events spread across 31 unique dates (all confined to the United States),
limiting its applicability. In contrast, Eventist contains news headlines describing 113 different
events, covering 688 unique dates, and a significantly longer narrative duration.

Table 1
Dataset Descriptives.
                  #Events   #Dates    #News    Mean Duration     Max Duration     Min Duration
    Crisisfacts         8       31    41,147            3.88                7                2
     Eventist         113      688    23,274           10.69               71                2

   Methods for Event Deduplication Heuristic-based event deduplication methods first
extract entities from texts, which are used as features for event deduplication. [10] deployed
a graph-based event merging strategy. [8] considered multiple metrics measuring temporal
similarity, string similarity, and entity similarity. [7] utilized external entities information
in a KG. KG-based approaches aim to directly link word-based event mentions to Wikipedia
[9]. While heuristic-based approaches can only identify texts of high similarity, KG-based
approaches fail to capture events not included in the KG.
   Representation of Event Temporal Relations Freksa’s cognitive perspective on time
and temporal reasoning, as elucidated in his work [21], offers a simplified version of Allen’s
interval-based temporal relations, comprising 13 distinct types [22]. Unlike Allen’s approach,
which presents a compositionally complete framework for temporal reasoning, Freksa’s semi-
interval-based representation acknowledges the uncertainty inherent in event boundaries and
measures temporal relations based on the occurrence of events. While Allen’s model may
be theoretically robust, it may not always align with the intricacies of narrative studies. In
this work, the temporality of events refers to the narrated time of events rather than their
actual occurrence. Viewing narratives as a point in time offers a coherent perspective, which
recognizes that narratives encapsulate a specific temporal snapshot rather than a comprehensive
depiction of events as they unfold in the real world.




                                                107
3. Dataset Construction
Figure 2 shows the dataset construction pipeline. This includes news acquisition and denoising,
headline pairs sampling and validation.




Figure 2: Dataset Construction Pipeline.


   News Acquisition News articles are initially collected from the Global Database of Events,
Language, and Tone (GDELT) [3], utilizing storm-related keywords such as storm, flood, hur-
ricane, typhoon, and tornado. The search spans from January 1, 2021, to September 1, 2023,
with English language restrictions, yielding 1,978,483 raw articles from 149 countries. After
identifying and removing 50.28% of duplicate entries, 983,775 unique news articles remain. Our
preliminary studies showed that the regular expressions-based GDELT search includes pages
where at least one keyword appears in the title, body, image caption, or advertisements. To refine
the selection to storm-related news, additional steps are taken, including cosine similarity-based
clustering, event type annotation, entity recognition, and temporal clustering.

3.1. Denoising Pipeline
The steps in denoising data are designed to construct a dataset with high precision. This entails
ensuring that each cluster uniquely refers to a specific event, and that all headlines within any
cluster reference the same event, despite potential narrative variations.
   Clustering on headlines To generate representations for event mentions, we employ a
pre-trained sentence transformer (all-MiniLM-L6-v21 ). Subsequently, we calculate a distance
matrix 𝑑 ∈ ℝ𝑛×𝑛 based on cosine similarity for 𝑛 sentence pairs. Clusters are established with
two criteria: 1) each cluster must comprise a minimum of 50 instances, and 2) cosine similarities
between every pair of instances must exceed 0.7. This process results in the retrieval of 786,944
news instances, organized into 264 clusters.
   Annotation on Event Type and GPE We used the Text REtrieval Conference Incident
Stream (TREC-IS) dataset to train an event type classifier for soft labeling clusters. TREC-IS is a
collection of microblog posts about pre-disaster, in-disaster, and post-disaster discussions [3]. It
contains gold-standard annotation of 118 events. Clusters are chosen if the majority of headlines
are predicted as tropical storms, hurricanes, floods, typhoons, or tornadoes. Additionally,
spaCy’s NER (en_core_web_md2 ) is used to annotate GPEs. Given the anticipated variations in

1
    https://huggingface.co/sentence-transformers/all-MiniLM-L6-v2
2
    https://spacy.io/models/en#en_core_web_md




                                                      108
narrative discourse within each cluster, differences in GPEs among headlines belonging to the
same cluster are expected. The annotated GPEs play a crucial role in the subsequent merging of
clusters.
   Temporal Clustering For each cluster, a one-dimensional temporal clustering algorithm
(DBSCAN) is employed to eliminate temporal outliers, with temporal information represented by
the news publish date. We adopted a temporal granularity of one day, setting min_samples = 3
and 𝜖 = 1, resulting in the removal of 752,429 headlines.
   Merging Clusters The remaining 34,515 continuous mentions form 278 clusters representing
storm-related disaster instances. These clusters encompass various narratives, including pre-
disaster, in-disaster and post-disaster information. The maximum overlapping ratio, denoted as
𝑟, between the GPEs in any pair of clusters (𝐶𝑖 and 𝐶𝑗 ) is computed using Equation 1.

                                                         |𝐶𝑖 ∩ 𝐶𝑗 |
                                              𝑟𝑖𝑗 =                                           (1)
                                                      max(|𝐶𝑖 |, |𝐶𝑗 |)

   To capture long events such as 2023 Cyclone Freddy,3 we allow a temporal gap of 10 days
between clusters. Two clusters are merged if (1) GPEs overlap ratio 𝑟𝑖𝑗 ≥ 0.5, and (2) minimum
between-cluster temporal distance 𝑑𝑖𝑗 = min𝑐∈𝐶𝑖 ,𝑐 ′ ∈𝐶𝑗 𝑑(𝑐, 𝑐 ′ ) ≤ 10. As a result, 263 unique
clusters are returned. To further examine the clustering quality, one domain expert manually
linked each cluster to a Wikidata entity of type “occurrence”4 and checked for geospatial and
temporal consistency between mentions and the actual event occurrences, concluding 113
unique clusters.

3.2. Dataset Validation
We randomly selected 5 headlines from each cluster, resulting in a total of 565 sampled headlines
for assessing cluster coherence and uniqueness. All headlines are shown at once. Cluster
coherence was evaluated using a 5-point Likert scale, with two human raters indicating the
extent to which media narratives described the same event, ranging from ”Strongly Disagree”
(1) to ”Strongly Agree” (5). The mean Likert response score for coherence was 𝑠𝑚𝑒𝑎𝑛 = 4.03,
Krippendorff’s alpha 𝛼 = 0.736. The uniqueness of events within each cluster was assessed
by determining whether each event was distinct within the set. Cohen’s kappa statistic for
uniqueness was 𝜅 = 1.


4. Benchmarks
Event deduplication is a binary classification task5 and event temporal ordering is a multiclass
classification task6 . We use a bi-encoder (siamese network structure) comparing DistilRoBERTa-
base, DistilBERT-base-cased, RoBERTa-base and BERT-base-cased. Consistent with [19], a
vector concatenation considering element-wise difference between both embedded vectors,
3
  The longest recorded tropical cyclone
4
  https://www.wikidata.org/wiki/Q1190554
5
  Two labels for event deduplication: same_event_instance, different_event_instance
6
  Three labels for temporal ordering: before, equal and after




                                                        109
𝑢 ⊕ 𝑣 ⊕ |𝑢 − 𝑣|, is later fed into a softmax classification layer. We used Adam optimizer with
learning rate 2e−5, and a linear learning rate warm-up over 10% of the training data. Number of
training epoch is 5. The dataset is partitioned to include clusters of varying sizes in each split
(Table 2), consisting of 9 large clusters (𝑁𝑐 ≥ 500), 48 medium-sized clusters (500 > 𝑁𝑐 ≥ 200),
and 58 small clusters (𝑁𝑐 < 200).

Table 2
Number of instances of different splits in the final dataset. Parentheses in #Events indicate the number
of events from a large/medium/small cluster.
                                            #Sampled headline pairs    #Sampled headline pairs
     Split       #Events    #Headlines
                                             (Event Deduplication)    (Event Temporal Ordering)
     Train   74(7/33/34)         17,449                     610,714                     872,448
     Valid     17(1/7/9)          2,455                      73,650                      73,650
     Test     24(1/8/15)          3,570                     107,100                     107,100

   Within each split, stratified sampling is applied to sample headline pairs, balancing date
distribution, label distribution, and event instance distribution in headline pairs. Each model is
run with three seeds, and all experiments are run with an NVIDIA RTX A6000 48 GB graphics
card. Table 3 shows the benchmark result over 4 seeds (0, 1, 2, 3).

Table 3
Benchmark Results.
                                          Event Deduplication   Event Temporal Ordering
              DistilRoBERTa-base                   81.90±3.03                55.07±0.24
             DistilBERT-base-cased                 89.02±4.98                56.59±0.47
                 RoBERTa-base                      77.33±2.37                56.76±0.67
               BERT-base-cased                     86.14±6.46                55.55±0.29

   The baseline result under the pairwise comparison task formulation reveals two significant
implications. Firstly, it demonstrates the feasibility of discriminating event instances using
only news headlines, as evidenced by the result in event deduplication. This suggests that the
denoising pipeline and event type detection mechanisms are effective in distinguishing how
different storm-related events are mentioned in the headlines. Secondly, the result highlights
the challenge of identifying the temporal ordering of headlines mentioning storm-related events.
This task proves to be much more complex compared to discriminating between individual event
instances. The nuanced temporal relationships and contextual dependencies within narratives
pose a greater difficulty in determining the chronological sequence of events discussed in news
articles.


5. Limitations and Discussions
5.1. Generalizability of the Proposed Denoising Pipeline
One noticeable ad-hoc component in the denoising pipeline that hinders generalizability is
the domain-specific event type detector, trained in a supervised learning fashion. We used




                                                   110
an event type detector on a gold-standard human-annotated dataset (TREC-IS) to annotate
event types to select news headlines classified as being storm-related. While this approach
prioritizes the accuracy of event type annotations, it limits the generalizability to different event
types. We highlight the importance of showcasing the practical implications of the relatively
under-explored task of event instance discrimination, exemplified by storm-related events.
However, advancements in zero-shot learning techniques, such as prompt-based approaches
leveraging Large Language Models (LLMs), offer promising avenues to replace the ad-hoc event
type detector, potentially enhancing the pipeline’s generalizability across diverse event types.
It is crucial to conduct a thorough evaluation of zero-shot event type detectors to ensure the
quality of annotations.

5.2. Event Temporal Ordering Beyond News Publication Date
We used news publication dates as features to identify the temporal order of any pair of news
headlines. This representation ignores the temporal lag between news publication and the
actual occurrence of events. We acknowledge the limitations of this approach, particularly in
extracting precise absolute temporal attributes of events. A more accurate method would involve
linking event mentions to well-structured data sources such as Knowledge Graphs (KGs) to
extract strictly precise temporal attributes. However, the task of event linking remains relatively
unexplored, with existing works primarily linking event mentions to community-driven sources
like Wikipedia, which may contain inaccurate, or false information [9].
   Despite the inherent limitations, leveraging news publication dates for temporal ordering
provides an approximate timeline of event developments within media narratives. This ap-
proach allows for the construction of a detailed narrative timeline, facilitating the identification
of in-disaster news reports and further extraction, normalization, and analysis of temporal
expressions.


6. Conclusion
In conclusion, we introduced the Eventist dataset, a comprehensive silver-standard dataset that
serves as a benchmark for two essential pairwise comparison tasks: event deduplication and
event temporal ordering. While we validated the dataset with human raters, it’s important to
note that it may contain noise introduced by biases inherent in the denoising pipeline. However,
our focus on event instance discrimination underscores the dataset’s significance and opens
avenues for further research in refining and enhancing these critical NLP tasks.


Acknowledgments
The authors acknowledge the financial support by the Federal Ministry for Economic Affairs
and Energy of Germany in the project CoyPu (project number 01MK21007G).




                                                111
References
[1] R. Méndez-Tejeda, J. J. Hernández-Ayala, Links between climate change and hurricanes in
    the North Atlantic, PLOS Climate 2 (2023) e0000186. URL: https://doi.org/10.1371/journal.
    pclm.0000186. doi:10.1371/journal.pclm.0000186.
[2] D. Xi, N. Lin, A. Gori, Increasing sequential tropical cyclone hazards along the US East
    and Gulf coasts, Nature Climate Change 13 (2023) 258–265. URL: https://doi.org/10.1038/
    s41558-023-01595-7. doi:10.1038/s41558-023-01595-7.
[3] R. McCreadie, C. Buntain, I. Soboroff, TREC incident streams: Finding actionable in-
    formation on social media, in: Z. Franco, J. J. González, J. H. Canós (Eds.), Proceed-
    ings of the 16th International Conference on Information Systems for Crisis Response
    and Management, València, Spain, May 19-22, 2019, ISCRAM Association, 2019. URL:
    http://idl.iscram.org/files/richardmccreadie/2019/1867_RichardMcCreadie_etal2019.pdf.
[4] R. McCreadie, C. Buntain, Crisisfacts: Buidling and evaluating crisis timelines, in: 20th
    International Conference on Information Systems for Crisis Response and Management (IS-
    CRAM 2023), Omaha, NE, USA, 2023, pp. 320–339. URL: https://doi.org/10.59297/JVQZ9405.
    doi:10.59297/JVQZ9405.
[5] G. R. Doddington, A. Mitchell, M. A. Przybocki, L. A. Ramshaw, S. M. Strassel, R. M.
    Weischedel, The automatic content extraction (ACE) program - Tasks, Data, and Evaluation,
    in: Proceedings of the Fourth International Conference on Language Resources and
    Evaluation, LREC 2004, May 26-28, 2004, Lisbon, Portugal, European Language Resources
    Association, 2004. URL: http://www.lrec-conf.org/proceedings/lrec2004/summaries/5.htm.
[6] X. Wang, Z. Wang, X. Han, W. Jiang, R. Han, Z. Liu, J. Li, P. Li, Y. Lin, J. Zhou, MAVEN:
    A massive general domain event detection dataset, in: B. Webber, T. Cohn, Y. He, Y. Liu
    (Eds.), Proceedings of the 2020 Conference on Empirical Methods in Natural Language
    Processing, EMNLP 2020, Online, November 16-20, 2020, Association for Computational
    Linguistics, 2020, pp. 1652–1671. URL: https://doi.org/10.18653/v1/2020.emnlp-main.129.
    doi:10.18653/V1/2020.EMNLP-MAIN.129.
[7] F. Rollo, L. Po, Crime event localization and deduplication, in: J. Z. Pan, V. A. M. Tamma,
    C. d’Amato, K. Janowicz, B. Fu, A. Polleres, O. Seneviratne, L. Kagal (Eds.), The Seman-
    tic Web - ISWC 2020 - 19th International Semantic Web Conference, Athens, Greece,
    November 2-6, 2020, Proceedings, Part II, volume 12507 of Lecture Notes in Computer
    Science, Springer, 2020, pp. 361–377. URL: https://doi.org/10.1007/978-3-030-62466-8_23.
    doi:10.1007/978-3-030-62466-8\_23.
[8] V. Zavarella, J. Piskorski, C. Ignat, H. Tanev, M. Atkinson, Mastering the media hype:
    Methods for deduplication of conflict events from news reports, in: A. M. Jorge, R. Cam-
    pos, A. Jatowt, A. Aizawa (Eds.), Proceedings of AI4Narratives - Workshop on Artificial
    Intelligence for Narratives in conjunction with the 29th International Joint Conference
    on Artificial Intelligence and the 17th Pacific Rim International Conference on Artificial
    Intelligence (IJCAI 2020), Yokohama, Japan, January 7th and 8th, 2021 (online event due to
    Covid-19 outbreak), volume 2794 of CEUR Workshop Proceedings, CEUR-WS.org, 2020, pp.
    29–34. URL: https://ceur-ws.org/Vol-2794/paper6.pdf.
[9] X. Yu, W. Yin, N. Gupta, D. Roth, Event linking: Grounding event mentions to wikipedia,
    in: A. Vlachos, I. Augenstein (Eds.), Proceedings of the 17th Conference of the European




                                            112
     Chapter of the Association for Computational Linguistics, EACL 2023, Dubrovnik, Croatia,
     May 2-6, 2023, Association for Computational Linguistics, 2023, pp. 2671–2680. URL:
     https://doi.org/10.18653/v1/2023.eacl-main.196. doi:10.18653/V1/2023.EACL-MAIN.196.
[10] W. Ai, J. Xu, H. Shao, Z. Wang, T. Meng, An entity event deduplication method based on
     connected subgraph, in: J. Yang, K. Li, W. Tu, Z. Xiao, L. Wang (Eds.), 7th International
     Conference on Systems and Informatics, ICSAI 2021, Chongqing, China, November 13-15,
     2021, IEEE, 2021, pp. 1–6. URL: https://doi.org/10.1109/ICSAI53574.2021.9664040. doi:10.
     1109/ICSAI53574.2021.9664040.
[11] O. Inel, L. Aroyo, Validation methodology for expert-annotated datasets: Event annotation
     case study, in: M. Eskevich, G. de Melo, C. Fäth, J. P. McCrae, P. Buitelaar, C. Chiarcos,
     B. Klimek, M. Dojchinovski (Eds.), 2nd Conference on Language, Data and Knowledge,
     LDK 2019, May 20-23, 2019, Leipzig, Germany, volume 70 of OASIcs, Schloss Dagstuhl -
     Leibniz-Zentrum für Informatik, 2019, pp. 12:1–12:15. URL: https://doi.org/10.4230/OASIcs.
     LDK.2019.12. doi:10.4230/OASICS.LDK.2019.12.
[12] Z. Song, A. Bies, S. M. Strassel, J. Ellis, T. Mitamura, H. T. Dang, Y. Yamakawa, S. Holm,
     Event nugget and event coreference annotation, in: M. Palmer, E. H. Hovy, T. Mitamura,
     T. O’Gorman (Eds.), Proceedings of the Fourth Workshop on Events, EVENTS@HLT-
     NAACL 2016, San Diego, California, USA, June 17, 2016, Association for Computational
     Linguistics, 2016, pp. 37–45. URL: https://doi.org/10.18653/v1/W16-1005. doi:10.18653/
     V1/W16-1005.
[13] C. Colruyt, O. D. Clercq, T. Desot, V. Hoste, EventDNA: A dataset for dutch news event
     extraction as a basis for news diversification, Lang. Resour. Evaluation 57 (2023) 189–221.
     URL: https://doi.org/10.1007/s10579-022-09623-2. doi:10.1007/S10579-022-09623-2.
[14] S. Liu, Y. Li, F. Zhang, T. Yang, X. Zhou, Event detection without triggers, in: J. Burstein,
     C. Doran, T. Solorio (Eds.), Proceedings of the 2019 Conference of the North American
     Chapter of the Association for Computational Linguistics: Human Language Technologies,
     NAACL-HLT 2019, Minneapolis, MN, USA, June 2-7, 2019, Volume 1 (Long and Short
     Papers), Association for Computational Linguistics, 2019, pp. 735–744. URL: https://doi.
     org/10.18653/v1/n19-1080. doi:10.18653/V1/N19-1080.
[15] T. Ling, L. Chen, H. Sheng, Z. Cai, H. Liu, Sentence-level event detection without trig-
     gers via prompt learning and machine reading comprehension, CoRR abs/2306.14176
     (2023). URL: https://doi.org/10.48550/arXiv.2306.14176. doi:10.48550/ARXIV.2306.14176.
     arXiv:2306.14176.
[16] A. Piper, R. J. So, D. Bamman, Narrative theory for computational narrative under-
     standing, in: M. Moens, X. Huang, L. Specia, S. W. Yih (Eds.), Proceedings of the 2021
     Conference on Empirical Methods in Natural Language Processing, EMNLP 2021, Virtual
     Event / Punta Cana, Dominican Republic, 7-11 November, 2021, Association for Computa-
     tional Linguistics, 2021, pp. 298–311. URL: https://doi.org/10.18653/v1/2021.emnlp-main.26.
     doi:10.18653/V1/2021.EMNLP-MAIN.26.
[17] S. Diaf, J. Döpke, U. Fritsche, I. Rockenbach, Sharks and minnows in a shoal of words:
     Measuring latent ideological positions based on text mining techniques, European Journal
     of Political Economy 75 (2022) 102179. URL: https://doi.org/10.1016/j.ejpoleco.2022.102179.
     doi:10.1016/j.ejpoleco.2022.102179.
[18] T. Zhang, A. M. Schoene, S. Ji, S. Ananiadou, Natural language processing applied to




                                              113
     mental illness detection: A narrative review, npj Digit. Medicine 5 (2022). URL: https:
     //doi.org/10.1038/s41746-022-00589-7. doi:10.1038/S41746-022-00589-7.
[19] N. Reimers, I. Gurevych, Sentence-BERT: Sentence embeddings using siamese BERT-
     networks, in: K. Inui, J. Jiang, V. Ng, X. Wan (Eds.), Proceedings of the 2019 Conference
     on Empirical Methods in Natural Language Processing and the 9th International Joint
     Conference on Natural Language Processing, EMNLP-IJCNLP 2019, Hong Kong, China,
     November 3-7, 2019, Association for Computational Linguistics, 2019, pp. 3980–3990. URL:
     https://doi.org/10.18653/v1/D19-1410. doi:10.18653/V1/D19-1410.
[20] S. Nishikawa, R. Ri, I. Yamada, Y. Tsuruoka, I. Echizen, EASE: Entity-aware contrastive
     learning of sentence embedding, in: M. Carpuat, M. de Marneffe, I. V. M. Ruíz (Eds.),
     Proceedings of the 2022 Conference of the North American Chapter of the Association
     for Computational Linguistics: Human Language Technologies, NAACL 2022, Seattle,
     WA, United States, July 10-15, 2022, Association for Computational Linguistics, 2022, pp.
     3870–3885. URL: https://doi.org/10.18653/v1/2022.naacl-main.284. doi:10.18653/V1/2022.
     NAACL-MAIN.284.
[21] C. Freksa, Temporal reasoning based on semi-intervals, Artif. Intell. 54 (1992) 199–227. URL:
     https://doi.org/10.1016/0004-3702(92)90090-K. doi:10.1016/0004-3702(92)90090-K.
[22] J. F. Allen, Maintaining knowledge about temporal intervals, Commun. ACM 26 (1983)
     832–843. URL: https://doi.org/10.1145/182.358434. doi:10.1145/182.358434.




                                              114