English

Standard deviation of the longest common subsequence

Probability 2009-07-30 v1

Abstract

Let LnL_n be the length of the longest common subsequence of two independent i.i.d. sequences of Bernoulli variables of length nn. We prove that the order of the standard deviation of LnL_n is n\sqrt{n}, provided the parameter of the Bernoulli variables is small enough. This validates Waterman's conjecture in this situation [Philos. Trans. R. Soc. Lond. Ser. B 344 (1994) 383--390]. The order conjectured by Chvatal and Sankoff [J. Appl. Probab. 12 (1975) 306--315], however, is different.

Keywords

Cite

@article{arxiv.0907.5137,
  title  = {Standard deviation of the longest common subsequence},
  author = {Jüri Lember and Heinrich Matzinger},
  journal= {arXiv preprint arXiv:0907.5137},
  year   = {2009}
}

Comments

Published in at http://dx.doi.org/10.1214/08-AOP436 the Annals of Probability (http://www.imstat.org/aop/) by the Institute of Mathematical Statistics (http://www.imstat.org)

R2 v1 2026-06-21T13:30:27.671Z