The pre-image problem in kernel methods.

James Tin-yau Kwok; Ivor Wai-hung Tsang

doi:10.1109/tnn.2004.837781

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The pre-image problem in kernel methods.

James Tin-yau Kwok·Ivor Wai-hung Tsang

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Abstract

In this paper, we address the problem of finding the pre-image of a feature vector in the feature space induced by a kernel. This is of central importance in some kernel applications, such as on using kernel principal component analysis (PCA) for image denoising. Unlike the traditional method which relies on nonlinear optimization, our proposed method directly finds the location of the pre-image based on distance constraints in the feature space. It is noniterative, involves only linear algebra and does not suffer from numerical instability or local minimum problems. Evaluations on performing kernel PCA and kernel clustering on the USPS data set show much improved performance.

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Algorithms Artificial Intelligence Cluster Analysis Computer Simulation Decision Support Techniques Feedback Image Interpretation, Computer-Assisted Information Storage and Retrieval Neural Networks, Computer Pattern Recognition, Automated Principal Component Analysis Comparative Study Evaluation Study Journal Article Research Support, Non-U.S. Gov't

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James Tin-yau Kwok, Ivor Wai-hung Tsang. 2004. The pre-image problem in kernel methods.. https://doi.org/10.1109/tnn.2004.837781

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