Bayesian Persuasion Mediating Cheap Talk
11 Pages Posted: 19 Oct 2020 Last revised: 16 May 2022
Date Written: September 25, 2020
Abstract
We examine a model of sequential communication with a receiver acting upon two sources of information. One is a cheap-talk sender who initially obtains information but reveals it imprecisely. The other is a mediator who expands on the revealed information using Bayesian persuasion. We prove that Bayesian persuasion makes the preceding cheap talk more informative if the sender benefits from the receiver's action. This result holds for any sender's utility function with a unique maximum. We also define a condition for collusion between the sender and the mediator, as well as characterise the cheap-talk partition for both direct and mediated cases. The model and results are then illustrated with a trade deal on an item appraised by a third party.
Keywords: Cheap talk, Bayesian persuasion, mediation
JEL Classification: C72, D82, D83
Suggested Citation: Suggested Citation