The standard model of a Bayesian game used in most applications assumes that players' beliefs are derived from a common knowledge prior on preference parameters. I analyze the robustness of equilibria of such games to perturbations in the information structure. In a type space environment...

That people estimate quantities, or have beliefs about them, is a daily observable phenomenon. People also quantify their beliefs, at least in theory, by ascribing to them probability numbers. It is shown that quantified beliefs and estimations give rise to the same model, that of a type space,...