Continuous Probability Distributions in Concurrent Games

Abstract

We present a model of concurrent games in which strategies are probabilistic and support both discrete and continuous distributions. This is a generalisation of the probabilistic concurrent strategies of Winskel, based on event structures. We first introduce measurable event structures, discrete fibrations of event structures in which each fibre is turned into a measurable space. We then construct a bicategory of measurable games and measurable strategies based on measurable event structures, and add probability to measurable strategies using standard techniques of measure theory. We illustrate the model by giving semantics to an affine, higher-order, probabilistic language with a type of real numbers and continuous distributions.