🤖 AI Summary
This work addresses the challenge of accurately and efficiently establishing node correspondences in unsupervised graph alignment by proposing a novel "global representation and alignment" paradigm. Departing from the conventional decoupled framework of "local representation, global alignment," the method unifies representation learning and alignment into a single integrated process. It leverages a global attention mechanism combined with hierarchical cross-graph optimal transport to achieve anchor-free alignment. Furthermore, an efficient variant, GlobAlign-E, is introduced, reducing the computational complexity of optimal transport from cubic to quadratic. Experimental results demonstrate that the proposed approach improves alignment accuracy by up to 20% and accelerates computation by an order of magnitude compared to existing optimal transport-based methods, offering significant advantages in both precision and efficiency.
📝 Abstract
Unsupervised graph alignment aims to find the node correspondence across different graphs without any anchor node pairs. Despite the recent efforts utilizing deep learning-based techniques, such as the embedding and optimal transport (OT)-based approaches, we observe their limitations in terms of model accuracy-efficiency tradeoff. By focusing on the exploitation of local and global graph information, we formalize them as the ``local representation, global alignment''paradigm, and present a new ``global representation and alignment''paradigm to resolve the mismatch between the two phases in the alignment process. We then propose \underline{Gl}obal representation and \underline{o}ptimal transport-\underline{b}ased \underline{Align}ment (\texttt{GlobAlign}), and its variant, \texttt{GlobAlign-E}, for better \underline{E}fficiency. Our methods are equipped with the global attention mechanism and a hierarchical cross-graph transport cost, able to capture long-range and implicit node dependencies beyond the local graph structure. Furthermore, \texttt{GlobAlign-E} successfully closes the time complexity gap between representative embedding and OT-based methods, reducing OT's cubic complexity to quadratic terms. Through extensive experiments, our methods demonstrate superior performance, with up to a 20\% accuracy improvement over the best competitor. Meanwhile, \texttt{GlobAlign-E} achieves the best efficiency, with an order of magnitude speedup against existing OT-based methods.