🤖 AI Summary
This work addresses the challenge of label scarcity in cross-city transfer learning caused by incompatible regional partitions and the absence of true correspondences. To tackle this, the authors propose an explicit soft correspondence modeling approach based on entropy-regularized optimal transport (OT). The method employs the Sinkhorn algorithm to learn interpretable soft matchings between regions of source and target cities and introduces target-guided prototype hubs as shared semantic anchors. Multi-source representation alignment is achieved through OT-weighted contrastive learning combined with cycle-consistent reconstruction regularization. Evaluated on multiple real-world urban datasets, the proposed framework significantly improves both transfer accuracy and robustness while offering an interpretable assessment of region alignment quality.
📝 Abstract
Cross-city transfer improves prediction in label-scarce cities by leveraging labeled data from other cities, but it becomes challenging when cities adopt incompatible partitions and no ground-truth region correspondences exist. Existing approaches either rely on heuristic region matching, which is often sensitive to anchor choices, or perform distribution-level alignment that leaves correspondences implicit and can be unstable under strong heterogeneity. We propose SCOT, a cross-city representation learning framework that learns explicit soft correspondences between unequal region sets via Sinkhorn-based entropic optimal transport. SCOT further sharpens transferable structure with an OT-weighted contrastive objective and stabilizes optimization through a cycle-style reconstruction regularizer. For multi-source transfer, SCOT aligns each source and the target to a shared prototype hub using balanced entropic transport guided by a target-induced prototype prior. Across real-world cities and tasks, SCOT consistently improves transfer accuracy and robustness, while the learned transport couplings and hub assignments provide interpretable diagnostics of alignment quality.