Is a nonincreasing expectation of a function value sequence a supermartingale sequence?

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Let $f: \mathbb{R}^n \times \omega \to \mathbb{R}$ where $\omega \sim D$. Assume $(f(x_k, \omega_k))$ be a random sequence such that

$$ \mathbb{E}_{\omega^{k+1}} [f(x_{k+1}, \omega_{k+1})] \leq f(x_{k}, \omega_{k}) $$ where $f(x_{k}, \omega_{k})$ is just a realization at the $k$-th step.

Question1

Is $(f(x_k, \omega_k))$ a supermartingale sequence?

Question2

If so, assuming $f$ is bounded below, can we show that $(f(x_k, \omega_k))$ converges to some random variable with probability one using Doob's martingale convergence theorems?