In this paper we are concerned
with the sample functions of increasing stochastic processes, Xν, having stationary,
independent increments; normalized so that Xν has no deterministic linear
component and Xν(0) = 0, (i.e., X∨ is a subordinator). For h a fixed function, we are
interested in the following two events: { ω : Xν(t,ω) > h(t) infinitely often as t → 0},
{ ω : Xν(t,ω) > h(t) infinitely often as t →∞}. In case Xν is a stable process,
Khinchin has given integral tests to apply to a wide class of h′s in order to decide
whether one, the other, or both of these two events have probability zero or one. The
purpose of this paper is to give similar results, without assuming Xu to be
stable.
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