An occupation-time density is identified for a class of absolutely continuous functions $x(t)$ in terms of $x'(t)$ and the number of times that $x(t)$ assumes the values in its range. This result is applied to stationary random processes with a finite second spectral moment. As a by-product, a generalization of Rice's formula for the mean number of crossings is obtained.
@article{1176997029,
author = {Geman, D. and Horowitz, J.},
title = {Occupation Times for Smooth Stationary Processes},
journal = {Ann. Probab.},
volume = {1},
number = {5},
year = {1973},
pages = { 131-137},
language = {en},
url = {http://dml.mathdoc.fr/item/1176997029}
}
Geman, D.; Horowitz, J. Occupation Times for Smooth Stationary Processes. Ann. Probab., Tome 1 (1973) no. 5, pp. 131-137. http://gdmltest.u-ga.fr/item/1176997029/