Abstract
This paper is devoted to the convergence analysis of stochastic approximation algorithms of the form θn+1 = θn + γn+1Hθn(Xn+1), where {θn, n ϵ ℕ} is an Rd-valued sequence, {γn, n ϵ N} is a deterministic stepsize sequence, and {Xn, n ϵ N} is a controlled Markov chain. We study the convergence under weak assumptions on smoothness-in-θ of the function θ → Hθ(x). It is usually assumed that this function is continuous for any x; in this work, we relax this condition. Our results are illustrated by considering stochastic approximation algorithms for (adaptive) quantile estimation and a penalized version of the vector quantization.
| Original language | English |
|---|---|
| Pages (from-to) | 866-893 |
| Number of pages | 28 |
| Journal | SIAM Journal on Control and Optimization |
| Volume | 54 |
| Issue number | 2 |
| DOIs | |
| Publication status | Published - 1 Jan 2016 |
| Externally published | Yes |
Keywords
- Controlled Markov chain
- Discontinuous dynamics
- State-dependent noise
- Stochastic approximation