Okay, Let's Do This! Modeling Event Coreference with Generated Rationales and Knowledge Distillation
Abhijnan Nath, Shadi Manafi, Avyakta Chelle, Nikhil Krishnaswamy
TL;DR
This work tackles event coreference resolution by leveraging abductive free-text rationales generated from an open-weight LLM as distant supervision. It introduces a two-stage training pipeline: Rationale-Oriented Event Clustering (ROEC) to align event pairs with generated rationales in a student encoder, and knowledge distillation to transfer rationale-informed cues from a teacher model into a compact model. Through experiments on ECB+, GVC, and AIDA Phase 1, the authors achieve state-of-the-art $B^3$ F1 on ECB+ and GVC and establish a new baseline on AIDA Phase 1, all without document clustering during inference. The approach demonstrates that LLM-generated rationales, when conditioned on gold labels and distilled into a smaller model, provide valuable contextual cues for coreference decisions, suggesting a practical path to more efficient, rationale-grounded ECR systems with potential applicability to other NLP tasks that benefit from explainable supervision.
Abstract
In NLP, Event Coreference Resolution (ECR) is the task of connecting event clusters that refer to the same underlying real-life event, usually via neural systems. In this work, we investigate using abductive free-text rationales (FTRs) generated by modern autoregressive LLMs as distant supervision of smaller student models for cross-document coreference (CDCR) of events. We implement novel rationale-oriented event clustering and knowledge distillation methods for event coreference scoring that leverage enriched information from the FTRs for improved CDCR without additional annotation or expensive document clustering. Our model using coreference specific knowledge distillation achieves SOTA B3 F1 on the ECB+ and GVC corpora and we establish a new baseline on the AIDA Phase 1 corpus. Our code can be found at https://github.com/csu-signal/llama_cdcr
