Random walks and the regeneration time
✍ Scribed by Beveridge, Andrew; Lov�sz, L�szl�
- Publisher
- John Wiley and Sons
- Year
- 1998
- Tongue
- English
- Weight
- 218 KB
- Volume
- 29
- Category
- Article
- ISSN
- 0364-9024
No coin nor oath required. For personal study only.
✦ Synopsis
Consider a graph G and a random walk on it. We want to stop the random walk at certain times (using an optimal stopping rule) to obtain independent samples from a given distribution ρ on the nodes. For an undirected graph, the expected time between consecutive samples is maximized by a distribution equally divided between two nodes, and so the worst expected time is 1/4 of the maximum commute time between two nodes. In the directed case, the expected time for this distribution is within a factor of 2 of the maximum.
📜 SIMILAR VOLUMES
Let G be a connected, undirected graph and Let N N be the nonnegative quadrant of the plane grid, and H the subgraph of N N induced by the sites i j for which X i = Y j . We say that G is "navigable" if with probability greater than 0, the origin belongs to an infinite component of H. We determine