Wasserstein-Fisher-Rao Embedding: Logical Query Embeddings with Local Comparison and Global Transport

Zihao Wang, Weizhi Fei, Hang Yin, Yangqiu Song, Ginny Wong, Simon See


Abstract
Answering complex queries on knowledge graphs is important but particularly challenging because of the data incompleteness. Query embedding methods address this issue by learningbased models and simulating logical reasoning with set operators. Previous works focus on specific forms of embeddings, but scoring functions between embeddings are underexplored. In contrast to existing scorning functions motivated by local comparison or global transport, this work investigates the local and global trade-off with unbalanced optimal transport theory. Specifically, we embed sets as bounded measures in R endowed with a scoring function motivated by the Wasserstein-Fisher-Rao metric. Such a design also facilitates closed-form set operators in the embedding space. Moreover, we introduce a convolution-based algorithm for linear time computation and a block diagonal kernel to enforce the trade-off. Results show that WFRE is capable of outperforming existing query embedding methods on standard datasets, evaluation sets with combinatorially complex queries, and hierarchical knowledge graphs. Ablation study shows that finding a better local and global trade-off is essential for performance improvement.
Anthology ID:
2023.findings-acl.864
Volume:
Findings of the Association for Computational Linguistics: ACL 2023
Month:
July
Year:
2023
Address:
Toronto, Canada
Editors:
Anna Rogers, Jordan Boyd-Graber, Naoaki Okazaki
Venue:
Findings
SIG:
Publisher:
Association for Computational Linguistics
Note:
Pages:
13679–13696
Language:
URL:
https://aclanthology.org/2023.findings-acl.864
DOI:
10.18653/v1/2023.findings-acl.864
Bibkey:
Cite (ACL):
Zihao Wang, Weizhi Fei, Hang Yin, Yangqiu Song, Ginny Wong, and Simon See. 2023. Wasserstein-Fisher-Rao Embedding: Logical Query Embeddings with Local Comparison and Global Transport. In Findings of the Association for Computational Linguistics: ACL 2023, pages 13679–13696, Toronto, Canada. Association for Computational Linguistics.
Cite (Informal):
Wasserstein-Fisher-Rao Embedding: Logical Query Embeddings with Local Comparison and Global Transport (Wang et al., Findings 2023)
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PDF:
https://aclanthology.org/2023.findings-acl.864.pdf