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arXiv · 1610.04576

Kernel Alignment Inspired Linear Discriminant Analysis

Shuai Zheng·Chris Ding
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Abstract

Kernel alignment measures the degree of similarity between two kernels. In this paper, inspired from kernel alignment, we propose a new Linear Discriminant Analysis (LDA) formulation, kernel alignment LDA (kaLDA). We first define two kernels, data kernel and class indicator kernel. The problem is to find a subspace to maximize the alignment between subspace-transformed data kernel and class indicator kernel. Surprisingly, the kernel alignment induced kaLDA objective function is very similar to classical LDA and can be expressed using between-class and total scatter matrices. This can be extended to multi-label data. We use a Stiefel-manifold gradient descent algorithm to solve this problem. We perform experiments on 8 single-label and 6 multi-label data sets. Results show that kaLDA has very good performance on many single-label and multi-label problems.

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Shuai Zheng, Chris Ding. 2016-10-14. Kernel Alignment Inspired Linear Discriminant Analysis. https://arxiv.org/abs/1610.04576

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