Respecting Temporal-Causal Consistency: Entity-Event Knowledge Graph for Retrieval-Augmented Generation
Ze Yu Zhang, Zitao Li, Yaliang Li, Bolin Ding, Bryan Kian Hsiang Low
Abstract
Retrieval-augmented generation (RAG) based on large language models often falters on narrative documents with inherent temporal structures. Standard unstructured RAG methods rely solely on embedding-similarity matching and lack any general mechanism to encode or exploit chronological information, while knowledge graph RAG (KG-RAG) frameworks collapse every mention of an entity into a single node, erasing the evolving context that drives many queries. To formalize this challenge and draw the community’s attention, we construct ChronoQA, a robust and discriminative QA benchmark that measures temporal, causal, and character consistency understanding in narrative documents (e.g., novels) under the RAG setting. We then introduce Entity-Event RAG (E 2RAG), a dual-graph framework that keeps separate entity and event subgraphs linked by a bipartite mapping, thereby preserving the temporal and causal facets needed for fine-grained reasoning. Across ChronoQA, our approach outperforms state-of-the-art unstructured and KG-based RAG baselines, with notable gains on causal and character consistency queries. E 2RAG therefore offers a practical path to more context-aware retrieval for tasks that require precise answers grounded in chronological information.- Anthology ID:
- 2026.eacl-long.90
- Volume:
- Proceedings of the 19th Conference of the European Chapter of the Association for Computational Linguistics (Volume 1: Long Papers)
- Month:
- March
- Year:
- 2026
- Address:
- Rabat, Morocco
- Editors:
- Vera Demberg, Kentaro Inui, Lluís Marquez
- Venue:
- EACL
- SIG:
- Publisher:
- Association for Computational Linguistics
- Note:
- Pages:
- 2017–2054
- Language:
- URL:
- https://preview.aclanthology.org/manual-author-scripts/2026.eacl-long.90/
- DOI:
- Cite (ACL):
- Ze Yu Zhang, Zitao Li, Yaliang Li, Bolin Ding, and Bryan Kian Hsiang Low. 2026. Respecting Temporal-Causal Consistency: Entity-Event Knowledge Graph for Retrieval-Augmented Generation. In Proceedings of the 19th Conference of the European Chapter of the Association for Computational Linguistics (Volume 1: Long Papers), pages 2017–2054, Rabat, Morocco. Association for Computational Linguistics.
- Cite (Informal):
- Respecting Temporal-Causal Consistency: Entity-Event Knowledge Graph for Retrieval-Augmented Generation (Zhang et al., EACL 2026)
- PDF:
- https://preview.aclanthology.org/manual-author-scripts/2026.eacl-long.90.pdf