Hessian Locally Linear Embedding

Abstract

Hessian locally linear embedding (HLLE) achieves linear embedding by minimizing the Hessian functional on the manifold where the data set resides. The conceptual framework of HLLE may be viewed as a modification of the Laplacian Eigenmaps framework. Let H be the observed high-dimensional data which reside on a low-dimentional manifold M and h be the coordinate mapping on M so that Y = h(H)is a DR of H. In Laplacian eigenmaps method, h is found in the numerically null space of the Laplace-Beltrsmi operator on M, while in Hessian locally linear embedding, it is found in the null space of the Hessian. Since HLLE embedding is locally linear, it works well for the data lying on a manifold that may not be convex. Compared with other nonlinear DR methods, such as Isomaps that need the data set lying on a convex manifold, HLLE can be applied to data in a wider range. The chapter is organized as follows. In Section 13.1, we describe the Hessian locally linear embedding method and its mathematical background. In Sections 13.2, the HLLE DR algorithm is introduced. The experiments of the algorithm are included in Section 13.3.