Discrepancy Convergence for the Drunkard's Walk on the Sphere

We analyze the drunkard's walk on the unit sphere with step size $\theta$ and show that the walk converges in order $C/\sin^2(\theta)$ steps in the discrepancy metric ($C$ a constant). This is an application of techniques we develop for bounding the discrepancy of random walks on Gelfand pairs generated by bi-invariant measures. In such cases, Fourier analysis on the acting group admits tractable computations involving spherical functions. We advocate the use of discrepancy as a metric on probabilities for state spaces with isometric group actions.

[1]  Alison L Gibbs,et al.  On Choosing and Bounding Probability Metrics , 2002, math/0209021.

[2]  F. Su,et al.  Random walks with badly approximable numbers , 2001, Unusual Applications of Number Theory.

[3]  F. Su A LeVeque-type lower bound for discrepancy , 2000 .

[4]  SU Francisedward CONVERGENCE OF RANDOM WALKS ON THE CIRCLE GENERATED BY AN IRRATIONAL ROTATION , 1998 .

[5]  Robert F. Tichy,et al.  Sequences, Discrepancies and Applications , 1997 .

[6]  M. Voit RATE OF CONVERGENCE TO GAUSSIAN MEASURES ON n-SPHERES AND JACOBI HYPERGROUPS , 1997 .

[7]  K. Maurin Representations of Compact Lie Groups , 1997 .

[8]  M. Voit Limit theorems for compact two-point homogeneous spaces of large dimensions , 1996 .

[9]  U. Porod The cut-off phenomenon for random reflections , 1996 .

[10]  M. Voit A Central-Limit-Theorem for Isotropic Random-Walks on n-Spheres for n → ∞ , 1995 .

[11]  H. Heyer,et al.  Harmonic Analysis of Probability Measures on Hypergroups , 1994 .

[12]  J. Rosenthal Random Rotations: Characters and Random Walks on SO(N) , 1994 .

[13]  Andrew Simon Greenhalgh,et al.  Random walks on groups with subgroup invariance properties , 1989 .

[14]  P. Diaconis Group representations in probability and statistics , 1988 .

[15]  P. Diaconis,et al.  Time to reach stationarity in the Bernoulli-Laplace diffusion model , 1987 .

[16]  G. Letac Problemes classiques de probabilite sur un couple de Gelfand , 1981 .

[17]  J. Dieudonne,et al.  Special Functions and Linear Representations of Lie Groups , 1980 .

[18]  William W. L. Chen On irregularities of distribution. , 1980 .

[19]  J.dieudonne Treatise On Analysis Vol-ii , 1976 .

[20]  Lauwerens Kuipers,et al.  Uniform distribution of sequences , 1974 .

[21]  J. Williamson,et al.  ABSTRACT HARMONIC ANALYSIS, VOL. II , 1972 .

[22]  J. Dieudonne Treatise on Analysis , 1969 .

[23]  R. Lipsman Abstract harmonic analysis , 1968 .

[24]  D. Jackson,et al.  fourier series and orthogonal polynomials , 1943, The Mathematical Gazette.