Automatic Mapping of Discourse Relations Across Different Annotation Frameworks

Core Concepts

Existing discourse corpora are annotated based on different frameworks, which show significant dissimilarities in definitions of arguments and relations. This study proposes a fully automatic method to learn label embeddings and map discourse relations from different frameworks, enabling integration of discourse theories and interoperability of discourse corpora.

Abstract

The content discusses the challenges in aligning discourse relations across different annotation frameworks, such as Rhetorical Structure Theory (RST) and Penn Discourse Treebank (PDTB). The key points are:

Discourse relations are important for achieving coherence, and automatic discourse relation classification is crucial for discourse parsing. However, existing discourse corpora are annotated based on different frameworks with significant dissimilarities.

The differences in discourse segmentation criteria, structural constraints, and relation inventories make it challenging to uncover the alignment of discourse relations used in different frameworks. Even with corpora annotated in multiple frameworks in parallel, expert knowledge and manual examination are typically required.

The paper proposes a fully automatic method to address this challenge. It extends the label-anchored contrastive learning approach to learn label embeddings during a classification task, which are then used to map discourse relations from different frameworks.

Experiments are conducted on RST-DT and PDTB 3.0 datasets. The results show that the learnt label embeddings can effectively capture the correlations between discourse relations across frameworks. Data augmentation is found to be helpful for improving the performance on the RST dataset.

An extrinsic evaluation is performed by relabeling PDTB explicit relations with RST labels based on the mapping results. The performance is slightly better than a previous manual mapping approach.

Stats

The agreement "an important step forward in the strengthened debt strategy" will "when implemented, provide significant reduction in the level of debt and debt service owed by Costa Rica." (implicit, given, Contingency.Cause.Reason)
that it will provide significant reduction in the level of debt and debt service owed by Costa Rica., implemented, (explicit, when, Temporal.Asynchronous.Succession)
that it will provide significant reduction in the level of debt and debt service owed by Costa Rica., implemented, (explicit, when, Contingency.Cause.Reason)

Quotes

"an important step forward in the strengthened debt strategy"
"when implemented, provide significant reduction in the level of debt and debt service owed by Costa Rica."

Key Insights Distilled From

Automatic Alignment of Discourse Relations of Different Discourse Annotation Frameworks

by Yingxue Fu at arxiv.org 04-01-2024

https://arxiv.org/pdf/2403.20196.pdf

Deeper Inquiries

How can the proposed method be extended to handle more fine-grained discourse relations or relations with lower frequencies

To handle more fine-grained discourse relations or relations with lower frequencies, the proposed method can be extended in several ways:

Data Augmentation: Increasing the amount of training data through techniques like data augmentation can help capture more nuanced relations and improve the model's ability to align them accurately.
Transfer Learning: Leveraging pre-trained language models that have been trained on a large corpus can provide a strong foundation for learning fine-grained relations. Fine-tuning these models on specific discourse relation tasks can help handle lower-frequency relations.
Hierarchical Label Embeddings: Introducing a hierarchical structure to the label embeddings can help capture relationships between fine-grained and higher-level relations. This can enable the model to generalize better to unseen or lower-frequency relations.
Ensemble Models: Combining multiple models trained on different subsets of relations or using different label encoders can enhance the model's ability to handle a wider range of relations, including those with lower frequencies.

What are the potential limitations of using label embeddings for discourse relation alignment, and how can they be addressed

Using label embeddings for discourse relation alignment may have some limitations, which can be addressed through the following strategies:

Data Imbalance: Addressing data imbalance by oversampling minority classes or using techniques like focal loss can help the model learn more effectively from lower-frequency relations.
Semantic Gap: Ensuring that the label embeddings capture the semantic nuances of the relations by incorporating additional information like label hierarchy or textual descriptions can improve alignment accuracy.
Evaluation Metrics: Using more robust evaluation metrics that consider the complexity and diversity of discourse relations can provide a better understanding of the model's performance and limitations.
Fine-tuning Strategies: Implementing fine-tuning strategies that focus on specific relation types or adjusting the model architecture to better capture subtle distinctions between relations can enhance alignment accuracy.

How can the insights from this study on discourse relation mapping be applied to improve downstream NLP tasks that rely on discourse information

The insights from this study on discourse relation mapping can be applied to improve downstream NLP tasks that rely on discourse information in the following ways:

Sentiment Analysis: By aligning discourse relations across different frameworks, sentiment analysis models can better understand the context and reasoning behind opinions expressed in text, leading to more accurate sentiment classification.
Text Summarization: Incorporating discourse relations into text summarization models can help generate more coherent and informative summaries by capturing the logical flow and structure of the original text.
Machine Comprehension: Enhancing machine comprehension models with aligned discourse relations can improve their ability to answer questions and infer meaning from text by considering the underlying discourse structure and relationships between entities.
Information Extraction: Leveraging aligned discourse relations can aid in extracting relevant information from text by providing a deeper understanding of how different pieces of information are connected and organized in a document.