Spherical Random Projection

Overview

1. Two files contain the functions for spherical random projection and cluster validation.

   • functions.R : Basic functions for operations on spheres (DIST, LOG, EXP, PARALLEL) and stability validation with spherical k-means clustering using a single core (cluster_stability, perturb_accept_rate) and multiple cores (mccluster_stability, mcperturb_accept_rate). Also, a function that validates the result of spectral clustering with multiple cores (mccluster_stability_spec).
   • spectral.R : spectral clustering for spherical data.

2. Three files contain the experiments on synthetic data sets.

   • experiment-vmf3.R: three mixtures of von Mises-Fisher distributions on 1000-dimensional sphere.

   • experiment-vmf5.R: five mixtures of von Mises-Fisher distributions on 2000-dimensional sphere.

   • experiment-bulls.R: two non spherical distributions on 1000-dimensional sphere.

3. Two files contain the experiment on real data sets.

   • real-face: analysis of JAFFE (Japanese Female Facial Expression) data set.
   • real-oz: analysis of the famous Oz books corpus.

Reference

• Seungwoo Kang and Hee-Seok Oh. (2024) Spherical Random Projection. Journal of the Royal Statistical Society Series B: Statistical Methodology. In press.