A Generalization Error Bound for Multi-class Domain Generalization
It addresses a theoretical gap in domain generalization for multi-class classification, which is incremental as it extends existing bounds to this setting.
The paper tackles the lack of theoretical analysis for multi-class domain generalization by establishing a generalization error bound that scales logarithmically with the number of classes, matching state-of-the-art bounds, and empirically shows the proposed algorithm outperforms a pooling strategy.
Domain generalization is the problem of assigning labels to an unlabeled data set, given several similar data sets for which labels have been provided. Despite considerable interest in this problem over the last decade, there has been no theoretical analysis in the setting of multi-class classification. In this work, we study a kernel-based learning algorithm and establish a generalization error bound that scales logarithmically in the number of classes, matching state-of-the-art bounds for multi-class classification in the conventional learning setting. We also demonstrate empirically that the proposed algorithm achieves significant performance gains compared to a pooling strategy.