Nous considérons une marche aléatoire centrée de variance finie et étudions le comportement asymptotique de la probabilité que l’aire sous la marche reste positive jusqu’à un grand temps . Si le moment d’ordre est fini, nous montrons que cette probabilité décroit comme . Pour prouver ce comportement asymptotique, nous développons une théorie du potentiel discrète pour des marches aléatoires intégrées.
We consider a centered random walk with finite variance and investigate the asymptotic behaviour of the probability that the area under this walk remains positive up to a large time . Assuming that the moment of order is finite, we show that the exact asymptotics for this probability is . To show this asymptotics we develop a discrete potential theory for integrated random walks.
@article{AIHPB_2015__51_1_167_0, author = {Denisov, Denis and Wachtel, Vitali}, title = {Exit times for integrated random walks}, journal = {Annales de l'I.H.P. Probabilit\'es et statistiques}, volume = {51}, year = {2015}, pages = {167-193}, doi = {10.1214/13-AIHP577}, mrnumber = {3300967}, zbl = {06412901}, language = {en}, url = {http://dml.mathdoc.fr/item/AIHPB_2015__51_1_167_0} }
Denisov, Denis; Wachtel, Vitali. Exit times for integrated random walks. Annales de l'I.H.P. Probabilités et statistiques, Tome 51 (2015) pp. 167-193. doi : 10.1214/13-AIHP577. http://gdmltest.u-ga.fr/item/AIHPB_2015__51_1_167_0/
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