An adaptive class pairwise dimensionality reduction algorithm

Support vector machines (SVM) has achieved great success in multi-class classification. However, with the increase in dimension, the irrelevant or redundant features may degrade the generalization performances of the SVM classifiers, which make dimensionality reduction (DR) become indispensable for high-dimensional data. At present, most of the DR algorithms reduce all data points to the same dimension for multi-class datasets, or search the local latent dimension for each class, but they neglect the fact that different class pairs also have different local latent dimensions. In this paper, we propose an adaptive class pairwise dimensionality reduction algorithm (ACPDR) to improve the generalization performances of the multi-class SVM classifiers. In the proposed algorithm, on the one hand, different class pairs are reduced to different dimensions; on the other hand, a tabu strategy is adopted to select adaptively a suitable embedding dimension. Five popular DR algorithms are employed in our experiment, and the numerical results on some benchmark multi-class datasets show that compared with the traditional DR algorithms, the proposed ACPDR can improve the generalization performances of the multi-class SVM classifiers, and also verify that it is reasonable to consider the different class pairs have different local dimensions.