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Principal Manifolds and Nonlinear Dimension Reduction via Local Tangent Space Alignment

Zhenyue Zhang·Hongyuan Zha
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Abstract

Nonlinear manifold learning from unorganized data points is a very challenging unsupervised learning and data visualization problem with a great variety of applications. In this paper we present a new algorithm for manifold learning and nonlinear dimension reduction. Based on a set of unorganized data points sampled with noise from the manifold, we represent the local geometry of the manifold using tangent spaces learned by fitting an affine subspace in a neighborhood of each data point. Those tangent spaces are aligned to give the internal global coordinates of the data points with respect to the underlying manifold by way of a partial eigendecomposition of the neighborhood connection matrix. We present a careful error analysis of our algorithm and show that the reconstruction errors are of second-order accuracy. We illustrate our algorithm using curves and surfaces both in 2D/3D and higher dimensional Euclidean spaces, and 64-by-64 pixel face images with various pose and lighting conditions. We also address several theoretical and algorithmic issues for further research and improvements.

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Zhenyue Zhang, Hongyuan Zha. 2002-12-07. Principal Manifolds and Nonlinear Dimension Reduction via Local Tangent Space Alignment. https://arxiv.org/abs/cs/0212008

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