Excursions of excited random walks on integers

Elena Kosygina (Baruch College and the CUNY Graduate Center)
Martin P. W. Zerner (University of Tuebingen)

Abstract


Several phase transitions for excited random walks on the integers are known to be characterized by a certain drift parameter $\delta\in\mathbb R$. For recurrence/transience the critical threshold is $|\delta|=1$, for ballisticity it is $|\delta|=2$ and for diffusivity $|\delta|=4$. In this paper we establish a phase transition at $|\delta|=3$. We show that the  expected return time of the walker to the starting point, conditioned on return, is finite iff $|\delta|>3$.  This result follows from an explicit description of the tail behaviour of the return time as a function of $\delta$, which is achieved by diffusion approximation of related branching processes by squared Bessel processes.

Full Text: Download PDF | View PDF online (requires PDF plugin)

Pages: 1-25

Publication Date: February 28, 2014

DOI: 10.1214/EJP.v19-2940

References

  • Afanasʹev, V. I. On the maximum of a critical branching process in a random environment. (Russian) Diskret. Mat. 11 (1999), no. 2, 86--102; translation in Discrete Math. Appl. 9 (1999), no. 3, 267--284 MR1712160
  • Alexander, Kenneth S. Excursions and local limit theorems for Bessel-like random walks. Electron. J. Probab. 16 (2011), no. 1, 1--44. MR2749771
  • Alili, S. Asymptotic behaviour for random walks in random environments. J. Appl. Probab. 36 (1999), no. 2, 334--349. MR1724844
  • Alon, Noga; Spencer, Joel H. The probabilistic method. Second edition. With an appendix on the life and work of Paul Erdős. Wiley-Interscience Series in Discrete Mathematics and Optimization. Wiley-Interscience [John Wiley & Sons], New York, 2000. xviii+301 pp. ISBN: 0-471-37046-0 MR1885388
  • Antal, T.; Redner, S. The excited random walk in one dimension. J. Phys. A 38 (2005), no. 12, 2555--2577. MR2132073
  • Athreya, Krishna B.; Karlin, Samuel. On branching processes with random environments. I. Extinction probabilities. Ann. Math. Statist. 42 (1971), 1499--1520. MR0298780
  • Athreya, K. B.; Ney, P. E. Branching processes. Reprint of the 1972 original [Springer, New York; MR0373040]. Dover Publications, Inc., Mineola, NY, 2004. xii+287 pp. ISBN: 0-486-43474-5 MR2047480
  • Basdevant, Anne-Laure; Singh, Arvind. On the speed of a cookie random walk. Probab. Theory Related Fields 141 (2008), no. 3-4, 625--645. MR2391167
  • Bauernschubert, Elisabeth. Perturbing transient random walk in a random environment with cookies of maximal strength. Ann. Inst. Henri Poincaré Probab. Stat. 49 (2013), no. 3, 638--653. MR3112429
  • E. Bauernschubert. Recurrence and transience of critical branching processes in random environment with immigration and an application to excited random walks. To appear in Adv. in Appl. Probab., 46(3), 2014. ARXIV1301.5450
  • Billingsley, Patrick. Convergence of probability measures. Second edition. Wiley Series in Probability and Statistics: Probability and Statistics. A Wiley-Interscience Publication. John Wiley & Sons, Inc., New York, 1999. x+277 pp. ISBN: 0-471-19745-9 MR1700749
  • Ethier, Stewart N.; Kurtz, Thomas G. Markov processes. Characterization and convergence. Wiley Series in Probability and Mathematical Statistics: Probability and Mathematical Statistics. John Wiley & Sons, Inc., New York, 1986. x+534 pp. ISBN: 0-471-08186-8 MR0838085
  • Feller, William. Diffusion processes in genetics. Proceedings of the Second Berkeley Symposium on Mathematical Statistics and Probability, 1950, pp. 227--246. University of California Press, Berkeley and Los Angeles, 1951. MR0046022
  • Formanov, Sh. K.; Yasin, Makhmud Takha; Kaverin, S. V. Life spans of Galton-Watson processes with migration. (Russian) Asymptotic problems in probability theory and mathematical statistics (Russian), 117--135, 175, "Fan'', Tashkent, 1990. MR1142599
  • Göing-Jaeschke, Anja; Yor, Marc. A survey and some generalizations of Bessel processes. Bernoulli 9 (2003), no. 2, 313--349. MR1997032
  • Harris, T. E. First passage and recurrence distributions. Trans. Amer. Math. Soc. 73, (1952). 471--486. MR0052057
  • Höpfner, R. A note on the probability of extinction in a class of population-size-dependent Galton-Watson processes. J. Appl. Probab. 22 (1985), no. 4, 920--925. MR0808871
  • Hughes, Barry D. Random walks and random environments. Vol. 1. Random walks. Oxford Science Publications. The Clarendon Press, Oxford University Press, New York, 1995. xxii+631 pp. ISBN: 0-19-853788-3 MR1341369
  • Ikeda, Nobuyuki; Watanabe, Shinzo. Stochastic differential equations and diffusion processes. Second edition. North-Holland Mathematical Library, 24. North-Holland Publishing Co., Amsterdam; Kodansha, Ltd., Tokyo, 1989. xvi+555 pp. ISBN: 0-444-87378-3 MR1011252
  • Ivanoff, B. Gail; Seneta, E. The critical branching process with immigration stopped at zero. J. Appl. Probab. 22 (1985), no. 1, 223--227. MR0776902
  • Jacod, Jean; Shiryaev, Albert N. Limit theorems for stochastic processes. Grundlehren der Mathematischen Wissenschaften [Fundamental Principles of Mathematical Sciences], 288. Springer-Verlag, Berlin, 1987. xviii+601 pp. ISBN: 3-540-17882-1 MR0959133
  • Kosygina, Elena; Mountford, Thomas. Limit laws of transient excited random walks on integers. Ann. Inst. Henri Poincaré Probab. Stat. 47 (2011), no. 2, 575--600. MR2814424
  • Kosygina, Elena; Zerner, Martin P. W. Positively and negatively excited random walks on integers, with branching processes. Electron. J. Probab. 13 (2008), no. 64, 1952--1979. MR2453552
  • Kosygina, Elena; Zerner, Martin P. W. Excited random walks: results, methods, open problems. Bull. Inst. Math. Acad. Sin. (N.S.) 8 (2013), no. 1, 105--157. MR3097419
  • Levin, David A.; Peres, Yuval; Wilmer, Elizabeth L. Markov chains and mixing times. With a chapter by James G. Propp and David B. Wilson. American Mathematical Society, Providence, RI, 2009. xviii+371 pp. ISBN: 978-0-8218-4739-8 MR2466937
  • Mellein, Bernhard. Kac functionals of diffusion processes approximating critical branching processes. Bol. Soc. Mat. Mexicana (2) 28 (1983), no. 2, 95--107. MR0791092
  • Pakes, A. G. On the critical Galton-Watson process with immigration. J. Austral. Math. Soc. 12 (1971), 476--482. MR0307370
  • Pakes, A. G. Further results on the critical Galton-Watson process with immigration. J. Austral. Math. Soc. 13 (1972), 277--290. MR0312585
  • J. Peterson. Strict monotonicity properties in one-dimensional excited random walks. Markov Process. Related Fields. 19(4):721--734, 2013. ARXIV1210.4518
  • Revuz, Daniel; Yor, Marc. Continuous martingales and Brownian motion. Third edition. Grundlehren der Mathematischen Wissenschaften [Fundamental Principles of Mathematical Sciences], 293. Springer-Verlag, Berlin, 1999. xiv+602 pp. ISBN: 3-540-64325-7 MR1725357
  • Rogers, L. C. G.; Williams, David. Diffusions, Markov processes, and martingales. Vol. 2. Itô calculus. Reprint of the second (1994) edition. Cambridge Mathematical Library. Cambridge University Press, Cambridge, 2000. xiv+480 pp. ISBN: 0-521-77593-0 MR1780932
  • Smith, Walter L.; Wilkinson, William E. On branching processes in random environments. Ann. Math. Statist. 40 1969 814--827. MR0246380
  • Solomon, Fred. Random walks in a random environment. Ann. Probability 3 (1975), 1--31. MR0362503
  • Tóth, Bálint. Generalized Ray-Knight theory and limit theorems for self-interacting random walks on ${\bf Z}^ 1$. Ann. Probab. 24 (1996), no. 3, 1324--1367. MR1411497
  • Yamada, Toshio; Watanabe, Shinzo. On the uniqueness of solutions of stochastic differential equations. J. Math. Kyoto Univ. 11 1971 155--167. MR0278420
  • Zerner, Martin P. W. Multi-excited random walks on integers. Probab. Theory Related Fields 133 (2005), no. 1, 98--122. MR2197139
  • A. M. Zubkov. Life-periods of a branching process with immigration. Theory Probab. Appl., 17(1):174--183, 1972. MR0300351


Creative Commons License
This work is licensed under a Creative Commons Attribution 3.0 License.