Oblique derivative problems and invariant measures
We study nonzero-sum multi-person multiple stopping games with players' priorities. The existence of Nash equilibrium is proved. Examples of multi stopping of Markov chains are considered. The game may also be presented as a special case of a stochastic game which leads to many variations of it, in which stopping is a part of players' strategies.
The author investigates non ergodic versions of several well known limit theorems for strictly stationary processes. In some cases, the assumptions which are given with respect to general invariant measure, guarantee the validity of the theorem with respect to ergodic components of the measure. In other cases, the limit theorem can fail for all ergodic components, while for the original invariant measure it holds.
In this note we give a proof of the fact that the extremal elements of the set of randomized stopping times are exactly the stopping times.
Necessary and sufficient conditions are found for the exponential Orlicz norm (generated by with 0 < p ≤ 2) of or to be finite, where is a standard Brownian motion and τ is a stopping time for B. The conditions are in terms of the moments of the stopping time τ. For instance, we find that as soon as for some constant C > 0 as k → ∞ (or equivalently ). In particular, if τ ∼ Exp(λ) or then the last condition is satisfied, and we obtain with some universal constant K > 0....