# Rationalizability in large games

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## Abstract

This paper characterizes both *point-rationalizability* and *rationalizability* in large games when societal responses are formulated as distributions or averages of individual actions. The sets of point-rationalizable and rationalizable societal responses are defined and shown to be convex, compact and equivalent to those outcomes that survive iterative elimination of never best responses, under point-beliefs and probabilistic beliefs, respectively. Given the introspection and mentalizing that rationalizability notions presuppose, one motivation behind the work is to examine their viability in situations where the terms *rationality* and *full information* can be given a more parsimonious, and thereby a more analytically viable, expression.

### Keywords

Large games Rationalizability Point-rationalizability Closed under rational behavior (CURB) Societal response### JEL Classification

C72 D80 C65### References

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