ON EXTREMAL INDEX OF MAX-STABLE STATIONARY PROCESSES
Krzysztof Dębicki
Enkelejd Hashorva
Abstract: In this contribution we discuss the relation between Pickands-type constants defined for
certain Brown–Resnick stationary process , as
(set if ) and the extremal index of the associated max-stable stationary
process . We derive several new formulas and obtain lower bounds for if is a
Gaussian or a Lévy process. As a by-product we show an interesting relation between
Pickands constants and lower tail probabilities for fractional Brownian motions.
2010 AMS Mathematics Subject Classification: Primary: 60G15; Secondary:
60G70.
Keywords and phrases: Extremal index, mean cluster index, Pickands constant, M3
representation, Brown–Resnick stationary, max-stable process, Gaussian process, Lévy
process.