MAST: A Multi-View Alignment Strategy for Optimal Transport-Based Contrastive Clustering of Short Text

Zijian Zheng, Yonghe Lu


Abstract
Short text clustering has gained significant prominence due to its ubiquity in real-world applications. Despite the recent success of contrastive clustering, existing paradigms still suffer from two critical bottlenecks: (1) conventional data augmentation provides limited semantic granularity and may introduce unintended noise; and (2) the absence of global optimization for cluster assignments often precipitates the accumulation of pseudo-label noise, thereby compromising semantic consistency. To bridge these gaps, we propose MAST, a Multi-view Alignment Strategy with Transport-based clustering. MAST constructs complementary structural views to capture multi-granularity semantic features and introduces a multi-view contrastive objective that jointly aligns original, augmented, and structure-enhanced embeddings. To mitigate representation over-smoothing, we incorporate structure-aware negative reweighting and intermediate-layer negative sampling. Furthermore, MAST employs high-confidence guided refinement and an optimal transport-based pseudo-label alignment mechanism to enforce global semantic consistency across multiple views. Extensive experiments on several benchmark datasets demonstrate that MAST consistently outperforms state-of-the-art methods, establishing a new competitive baseline for short text clustering.
Anthology ID:
2026.findings-acl.660
Volume:
Findings of the Association for Computational Linguistics: ACL 2026
Month:
July
Year:
2026
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San Diego, California, United States
Editors:
Maria Liakata, Viviane P. Moreira, Jiajun Zhang, David Jurgens
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Findings
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Publisher:
Association for Computational Linguistics
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Pages:
13483–13500
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https://preview.aclanthology.org/ingest-acl/2026.findings-acl.660/
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Cite (ACL):
Zijian Zheng and Yonghe Lu. 2026. MAST: A Multi-View Alignment Strategy for Optimal Transport-Based Contrastive Clustering of Short Text. In Findings of the Association for Computational Linguistics: ACL 2026, pages 13483–13500, San Diego, California, United States. Association for Computational Linguistics.
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MAST: A Multi-View Alignment Strategy for Optimal Transport-Based Contrastive Clustering of Short Text (Zheng & Lu, Findings 2026)
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