A Theory of Influence ∗

We analyze a game where one agent (the “leader”) decides first how much free information he collects, and then how much of this information he transmits to another agent (the “decisionmaker”). Conditional on the information disclosed, the decision-maker undertakes an action that affects the payoff of both agents. We assume a conflict of preferences between the two agents and rely on previous research to argue that, in this context and with verifiable information, the leader will not obtain rents from his possession of private information. We then show that the leader will nonetheless obtain some rents due to his ability to decide whether to collect or forego information, that is due to his control of the generation of information. The paper provides an analytical characterization of these rents. We interpret them as the degree of influence that, e.g., mass media and defending counsels can exert on citizens and juries thanks to their discretion in the selection of news covered and their ability to proceed or stop interrogations, respectively. ∗Correspondence address: Isabelle Brocas, Department of Economics, Columbia University, 1009B IAB, 420 West 118 St, New York, NY 10027, email: or Juan D. Carrillo, Columbia Business School, Uris Hall 812, 3022 Broadway, New York, NY 10027, e-mail: . We thank seminar participants at Columbia, Rochester, Michigan and Duke for helpful comments.