2025/10/08 by Dębicki, Krzysztof, Hashorva, Enkelejd, Michna, Zbigniew
#FOS: Mathematics #Primary 60G15 #Probability (math.PR) #secondary 60G70
paper · doi:10.48550/arxiv.2510.06930
For a centered, homogeneous Rd-valued Gaussian random field X(t), t in Rk, with covariance matrix function R(s,t) = E[X(s) X(t)T], we investigate the exact asymptotics of kappau(x) = P( theta(u) * integral over [0,T]k of 1X(t) > u b dt > x ), where b = (b1, ..., bd)T, as u -> infinity, with x >= 0 and T > 0, and theta(u) is a scaling function related to the expansion of R(s,t) around (0,0). To approximate kappau(x), we extend both Berman's original approach and the uniform double-sum method to the multivariate setting. Furthermore, we derive the exact asymptotics for the supremum of X, thus extending several recent results in the literature.