We study the design of informational environments in settings where generating information is costly. We assume that the cost of a signal is proportional to the expected reduction in uncertainty. We show that Kamenica & Gentzkow's (2011) concavification approach to characterizing optimal signals...

When is it possible for one person to persuade another to change her action? We consider a symmetric information model where a sender chooses a signal to reveal to a receiver, who then takes a noncontractible action that affects the welfare of both players. We derive necessary and sufficient...