EventEA: Benchmarking Entity Alignment for Event-centric Knowledge Graphs

Entity alignment is to find identical entities in different knowledge graphs (KGs) that refer to the same real-world object. Embedding-based entity alignment techniques have been drawing a lot of attention recently because they can help solve the issue of symbolic heterogeneity in different KGs. However, in this paper, we show that the progress made in the past was due to biased and unchallenging evaluation. We highlight two major flaws in existing datasets that favor <PRE_TAG>embedding-based <PRE_TAG><PRE_TAG>entity alignment</POST_TAG></POST_TAG> techniques</POST_TAG>, i.e., the isomorphic graph structures in relation triples and the weak heterogeneity in attribute triples. Towards a critical evaluation of embedding-based <PRE_TAG><PRE_TAG>entity alignment</POST_TAG></POST_TAG> methods, we construct a new dataset with heterogeneous relations and attributes based on event-centric KGs. We conduct extensive experiments to evaluate existing popular methods, and find that they fail to achieve promising performance. As a new approach to this difficult problem, we propose a time-aware literal encoder for <PRE_TAG>entity alignment</POST_TAG>. The dataset and source code are publicly available to foster future research. Our work calls for more effective and practical embedding-based solutions to <PRE_TAG>entity alignment</POST_TAG>.