Intrinsic location functionals of stationary processes. (English) Zbl 1320.60094
Summary: We consider a large family of measurable functionals of the sample path of a stochastic process over compact intervals. This family of functionals, which we call intrinsic location functionals, includes first hitting times, leftmost location of the supremum, etc. Despite the large variety of these functionals and their different nature, we show that for stationary processes the distribution of any intrinsic location functional over an interval is absolutely continuous in the interior of the interval, and the density functions always have a version satisfying the same total variation constraints. Conversely, these total variation constraints are shown to actually characterize stationarity of the underlying stochastic process. We also show that the possible distributions of the intrinsic location functionals over an interval form a weakly closed convex set and describe its extreme points, and present applications of this description.