Robust equilibria in cheap-talk games with fairly transparent motives

TL;DR

This paper characterizes robust equilibria in cheap-talk games with binary states and state-independent preferences, showing that the sender's optimal equilibrium is always robust to small changes in sender motives.

Contribution

It provides a complete characterization of which equilibria are robust in such games and proves the sender's optimal equilibrium is always among them.

Findings

Sender's optimal equilibrium is always robust.

Not all equilibria are robust to small state-dependence.

The paper characterizes conditions for robustness in cheap-talk games.

Abstract

For cheap-talk games with a binary state space in which the sender has state-independent preferences, we characterize equilibria that are robust to introducing slight state-dependence on the side of the sender. Not all equilibria are robust, but the sender-optimum is always achieved at some robust equilibrium.