Visual Representations of Temporal Relations between Events and Time Expressions in News Stories (2025)

Abstract: High-quality annotation is paramount for effective predictions of machine learning models. When the annotation is dense, achieving superior human labeling can be challenging since the most used annotation tools present an overloaded visualization of labels. Thus, we present a tool for viewing annotations made in corpora, specifically for temporal relations between events and temporal expressions, filling a gap in this type of tool. We focus on narrative text, which is a rich source for these types of elements.

## introduction events and time expressions are essential elements in news stories. they both contribute to the narrative structure by linking actions, facts, and developments to specific points in time, helping readers grasp the sequence, causality, and context of events. additionally, the relationship between events and time expressions plays a crucial role in establishing a timeline of occurrences. annotating events and time expressions and their relations is a well-known task in nlp @xcite @xcite @xcite . therefore, several formats have been proposed to visually present this information to a lay target audience @xcite , like timelines @xcite , infographics @xcite , and data comic @xcite . however, these representations often lack the precision and focus needed for expert audiences, whose primary goal is to analyze data and inspect annotations in detail. some visual representations, such as the message sequence chart (msc), have been used for this purpose @xcite . however, these approaches do not specifically address the representation of events combined with time expressions in a visually intuitive manner, which would help in identifying annotation mistakes. this gap highlights the need for specialized visual tools that cater to the demands of expert users in tasks like annotation analysis and narrative inspection. to address this gap, this work explores the following research questions: rq1 which insights can be derived from visualizing the events and temporal expressions, and their temporal relationships? rq2 how effective is isolating time expressions and their related events, and arranging them on a timeline, for facilitating annotation inspection by expert audiences? the first research question is whether the proposed visualization is suitable for representing temporal relations between events and time expressions in narratives. the usefulness of the visualization will be evaluated according to its capability to detect annotation errors and uncover relations between key narrative components or issues about the annotation scheme. thus, we will characterize the text2story lusa corpus, which is a narrative dataset manually annotated with portuguese news stories @xcite using vitra (visualizer of temporal relation annotations), our proposed visualization. the corpus was annotated using the brat annotation tool @xcite , and then, for this investigation, we converted the brat standoff file format to the json format, which is a more general format. to this conversion, we employ the text2story package @xcite , which also offers conversions from other types of annotation files. the second research question concerns its usability for the annotator. we elaborated on a questionnaire with six claims that intend to evaluate the overall design of the vitra tool. linguist experts with annotation experience were called to answer the proposed questionnaire. by answering these research questions, the contributions of this work are the following: our goal is to advance research on multi-layer dataset annotation by improving annotation quality through the integration of a visualization tool. additionally, we aim to provide insights into the design and application of the proposed annotation scheme. ## related work the two fundamental concepts of our work are temporal relations between events and time expressions and their visualizations. both have been extensively studied in recent years. therefore, we divide this section into two parts to discuss research related to each topic. the first part discusses similar works about temporal relations. the second part is the visualization of temporal information. ## methodology our methodology comprises two main steps that we detail below: data analysis of a subset from a portuguese news stories dataset and the visual tool. ## results and discussion our results are divided into data characterization regarding temporal information and the assessment of the visual tool proposed in this work. ## conclusion and future work in this study, we investigate the application of visualization representation in the inspection of temporal relations involving events and time expressions. narratives present dense information concerning events and time expressions. hence, human annotators are presented with visually overloaded information in annotation tools when labeling narratives. in this investigation, we used a portuguese dataset of news stories to answer the following research question. rq1) what insights can be derived from visualizing the events and temporal expressions and their temporal relationships in our results, we showed that some unusual patterns in the temporal relations can be easily detected in the visualization of temporal expressions, events, and their relations. this is probably due to the nature of the proposed visualization, which sets aside temporal expressions, their related events, and their relations. in the brat annotation tool, and usually in text annotation tools for documents, the raw text is presented along with all the relations and all entities. however, when facing a multilayer scheme, annotators can be challenged using a visualization like brat since this is a more complex task. thus, answering the first research question, we conclude that unusual patterns in a multilayer annotation scheme are more salient in a visual representation that is devoted to the specific layers on which the focus of the investigation is. some specific and relevant insights for our studied annotation scheme were observed, leading to adjustments in the annotation guidelines. a few use cases of insights are detailed in appendix c. rq2) how effective is isolating time expressions and their related events, and arranging them on a timeline, for facilitating annotation inspection by expert audiences? isolating was beneficial for human annotators. in our questionnaire, the annotator experts positively assessed the identification of events, time expression, and their relations. hence, all of them agreed that the proposed visualization facilitates the process of identifying errors or patterns. we aim to advance the study of visual representations for human annotators as well as the quality of multilayer scheme annotations, which present complexities and challenges in development and assessment. in future work, we intend to add other annotation formats to vitra, which can allow different types of arrangements, like the events in a timeline or even participants. additionally, we plan to integrate vitra into the inception annotation tool @xcite , which is a more modern tool than brat. by doing this, we seek to stimulate human annotators to use our tool to aid the labeling process.