On considère des marches aléatoires excitées sur ℤ avec un nombre borné de cookies i.i.d. à chaque site, ceci sans l'hypothèse de positivité. Auparavant, Kosygina et Zerner [15] ont établi que si la dérive totale moyenne par site, δ, est strictement supérieur à 1, alors la marche est transiente (vers la droite) et, de plus, pour δ>4 il y a un théorème central limite pour la position de la marche. Ici, on démontre que pour δ∈(2, 4] cette position, convenablement centrée et réduite, converge vers une loi stable de paramètre δ/2. L'approche permet également d'étendre les résultats de Basdevant et Singh [2] pour δ∈(1, 2] à notre cadre plus général.
We consider excited random walks (ERWs) on ℤ with a bounded number of i.i.d. cookies per site without the non-negativity assumption on the drifts induced by the cookies. Kosygina and Zerner [15] have shown that when the total expected drift per site, δ, is larger than 1 then ERW is transient to the right and, moreover, for δ>4 under the averaged measure it obeys the Central Limit Theorem. We show that when δ∈(2, 4] the limiting behavior of an appropriately centered and scaled excited random walk under the averaged measure is described by a strictly stable law with parameter δ/2. Our method also extends the results obtained by Basdevant and Singh [2] for δ∈(1, 2] under the non-negativity assumption to the setting which allows both positive and negative cookies.
@article{AIHPB_2011__47_2_575_0, author = {Kosygina, Elena and Mountford, Thomas}, title = {Limit laws of transient excited random walks on integers}, journal = {Annales de l'I.H.P. Probabilit\'es et statistiques}, volume = {47}, year = {2011}, pages = {575-600}, doi = {10.1214/10-AIHP376}, mrnumber = {2814424}, zbl = {1215.60057}, language = {en}, url = {http://dml.mathdoc.fr/item/AIHPB_2011__47_2_575_0} }
Kosygina, Elena; Mountford, Thomas. Limit laws of transient excited random walks on integers. Annales de l'I.H.P. Probabilités et statistiques, Tome 47 (2011) pp. 575-600. doi : 10.1214/10-AIHP376. http://gdmltest.u-ga.fr/item/AIHPB_2011__47_2_575_0/
[1] On the speed of a cookie random walk. Probab. Theory Related Fields 141 (2008) 625-645. | MR 2391167 | Zbl 1141.60383
and .[2] Rate of growth of a transient cookie random walk. Electron. J. Probab. 13 (2008) 811-851. | MR 2399297 | Zbl 1191.60107
and .[3] Excited random walk. Electron. Comm. Probab. 8 (2003) 86-92. | MR 1987097 | Zbl 1060.60043
and .[4] Central limit theorem for the excited random walk in dimension d≥2. Elect. Comm. in Probab. 12 (2007) 303-314. | MR 2342709 | Zbl 1128.60082
and .[5] Pathwise uniqueness for perturbed versions of Brownian motion and reflected Brownian motion. Probab. Theory Related Fields 113 (1999) 519-534. | MR 1717529 | Zbl 0945.60082
and .[6] Brownian motion and random walk perturbed at extrema. Probab. Theory Related Fields 113 (1999) 501-518. | MR 1717528 | Zbl 0930.60041
.[7] Central limit theorem for excited random walk in the recurrent regime. Preprint, 2008. | MR 2831235
.[8] Probability: Theory and Examples, 2nd edition. Duxbury Press, Belmont, CA, 1996. | MR 1609153 | Zbl 1202.60002
.[9] Stopped Random Walks. Limit Theorems and Applications. Applied Probability. A Series of the Applied Probability Trust 5. Springer, New York, 1988. | MR 916870 | Zbl 0634.60061
.[10] Markov Processes. Wiley, New York, 1986. | MR 838085 | Zbl 0592.60049
and .[11] An Introduction to Probability Theory and Its Applications, Vol. II, 2nd edition. Wiley, New York, 1971. | MR 270403 | Zbl 0138.10207
.[12] Life spans of Galton-Watson processes with migration (Russian). In Asymptotic Problems in Probability Theory and Mathematical Statistics 117-135. T. A. Azlarov and S. K. Formanov (Eds). Fan, Tashkent, 1990. | MR 1142599
, and .[13] Monotonicity for excited random walk in high dimensions, 2008. Available at arXiv:0803.1881v2 [math.PR]. | MR 2594356 | Zbl 1193.60123
and .[14] A limit law for random walk in random environment. Compos. Math. 30 (1975) 145-168. | Numdam | MR 380998 | Zbl 0388.60069
, and .[15] Positively and negatively excited random walks, with branching processes. Electron. J. Probab. 13 (2008) 1952-1979. | MR 2453552 | Zbl 1191.60113
and .[16] Random walk in a one-dimensional random medium. Teor. Verojatn. Primen. 18 (1973) 406-408. | MR 319274 | Zbl 0299.60054
.[17] Excited random walk in three dimensions has positive speed. Preprint, 2003. Available at arXiv:0310305v1 [math.PR].
.[18] On the speed of the one-dimensional excited random walk in the transient regime. ALEA 2 (2006) 279-296. | MR 2285733 | Zbl 1115.60103
, and .[19] Multi-excited random walks on integers. Probab. Theory Related Fields 133 (2005) 98-122. | MR 2197139 | Zbl 1076.60088
.[20] Recurrence and transience of excited random walks on ℤd and strips. Electron. Comm. Probab. 11 (2006) 118-128. | MR 2231739 | Zbl 1112.60086
.