Mediated Persuasion

TL;DR

This paper analyzes a strategic information design game involving a sender, mediator, and receiver, revealing conditions under which information is disclosed and how mediation affects outcomes, with implications for equilibrium and belief manipulation.

Contribution

It introduces a novel framework for understanding mediated persuasion, characterizes conditions for information revelation, and provides computational insights into feasible belief sets.

Findings

The sender never benefits from mediation.

The receiver can benefit from mediation under certain preference alignments.

Mediation can lead to more information revelation when the mediator's preferences are intermediate between sender and receiver.

Abstract

We study a game of strategic information design between a sender, who chooses state-dependent information structures, a mediator who can then garble the signals generated from these structures, and a receiver who takes an action after observing the signal generated by the first two players. We characterize sufficient conditions for information revelation, compare outcomes with and without a mediator and provide comparative statics with regard to the preferences of the sender and the mediator. We also provide novel conceptual and computational insights about the set of feasible posterior beliefs that the sender can induce, and use these results to obtain insights about equilibrium outcomes. The sender never benefits from mediation, while the receiver might. Strikingly, the receiver benefits when the mediator's preferences are not perfectly aligned with hers; rather the mediator should prefer more information revelation than the sender, but less than perfect revelation.