Blockchain Mediated Persuasion

Abstract

An ex-post informed Sender wishes to persuade a rational Bayesian Receiver to take a desired action, as in the classic Bayesian Persuasion model studied by Kamenica and Gentzkow (2011). However, we consider settings in which Sender cannot reliably commit to a signal mechanism. An alternative approach is to consider a trustworthy mediator that receives a reported state of the world from Sender and then, based on this report, generates a signal realization for Receiver. Such mediation can be implemented via costly blockchain technology. Surprisingly, we show that this cost differentiated mediation succeeds where free mediation fails. By requiring Sender to pay the mediator for different signal realizations, we can effectively incentivize them to truthfully report, which in turn allows for beneficial persuasion to take place.

Keywords: Bayesian persuasion, commitment, information design, smart contracts, blockchain