Learning Rotations Online

In this paper we show that the matrix von Mises-Fisher (vMF) distribution is a reasonable distribution upon which to build an online density estimation scheme for rotation matrices. We also consider a special case, the unit circle, for initial experimentation. The vector and matrix vMF distributions admit online algorithms in terms of their expectation parameters as a direct result of their exponential family nature, however proving regret bounds for these algorithms is arrested by the complexity of the cumulant functions for these distributions. In closing, we volunteer hazards and suggestions for immediate future work.

[1]  K. Pearson Biometrika , 1902, The American Naturalist.

[2]  Rayleigh The Problem of the Random Walk , 1905, Nature.

[3]  D. Flinn Orientation Statistics , 1967, Nature.

[4]  K. Mardia,et al.  Maximum Likelihood Estimators for the Matrix Von Mises-Fisher and Bingham Distributions , 1979 .

[5]  D. Hestenes,et al.  Lie-groups as Spin groups. , 1993 .

[6]  Y. Chikuse Statistics on special manifolds , 2003 .

[7]  Manfred K. Warmuth,et al.  Relative Loss Bounds for On-Line Density Estimation with the Exponential Family of Distributions , 1999, Machine Learning.

[8]  X. Pennec Probabilities and Statistics on Riemannian Manifolds : A Geometric approach , 2004 .

[9]  R. Rosenfeld Nature , 2009, Otolaryngology--head and neck surgery : official journal of American Academy of Otolaryngology-Head and Neck Surgery.