Noise-induced Regime Shifts: A Quantitative Characterization

TL;DR

This paper introduces a new quantitative measure called the propensity transition point to identify noise-driven regime shifts in complex dynamical systems, demonstrated through ecological, genetic, and experimental data.

Contribution

It proposes a novel quantitative indicator for stochastic regime shifts and demonstrates its applicability across different biological models and experimental data.

Findings

Propensity transition point effectively indicates noise-driven regime shifts.

Method applied successfully to ecological and genetic models.

Validated with experimental data on mycobacterial persistence.

Abstract

Diverse complex dynamical systems are known to exhibit abrupt regime shifts at bifurcation points of the saddle-node type. The dynamics of most of these systems, however, have a stochastic component resulting in noise driven regime shifts even if the system is away from the bifurcation points. In this paper, we propose a new quantitative measure, namely, the propensity transition point as an indicator of stochastic regime shifts. The concepts and the methodology are illustrated for the one-variable May model, a well-known model in ecology and the genetic toggle, a two-variable model of a simple genetic circuit. The general applicability and usefulness of the method for the analysis of regime shifts is further demonstrated in the case of the mycobacterial switch to persistence for which experimental data are available.