English

Collective behavior under catastrophes

Probability 2022-11-03 v1

Abstract

We introduce the following discrete time model. Each natural number represents an ecological niche and is assigned a fitness in (0,1)(0,1). All the sites are updated simultaneously at every discrete time. At any given time the environment may be normal with probability pp or a catastrophe may occur with probability 1p1-p. If the environment is normal the fitness of each site is replaced by the maximum of its current fitness and a random number. If there is a catastrophe the fitness of each site is replaced by a random number. We compute the joint fitness distribution of any finite number of sites at any fixed time. We also show convergence of this system to a stationary distribution. This too is computed explicitly.

Keywords

Cite

@article{arxiv.2211.00751,
  title  = {Collective behavior under catastrophes},
  author = {Rinaldo B. Schinazi},
  journal= {arXiv preprint arXiv:2211.00751},
  year   = {2022}
}
R2 v1 2026-06-28T04:58:05.858Z