Building upon Freidlin and Wentzell's (1984) theory of large deviations for continuous time-processes, Dean Foster and Peyton Young (1990) developed the more powerful concept of stochastic stability: "The stochastically stable set [SSS] is the set of states such that, in the long run, it is nearly certain that the system lies within every open set containing S as the noise tends slowly to zero" [p. 221]. This solution concept created a major impact in economics and game theory after Young (1993) developed a more tractable version of the theory for general finite-state Markov chains.
Building upon Freidlin and Wentzell's work on large deviations for continuous time processes, Foster and Young (1990) introduced the concept of stochastic stability. This idea states that a system is likely to remain within any open set as noise decreases over time. Young (1993) further simplified this theory for general finite-state Markov chains, making it more applicable in economics and game theory.