Mar 14, 2013 Filed in: Publications
With Joel Watson
Forthcoming in Econometrica.
Abstract: This paper proposes a new approach to equilibrium selection in repeated games with transfers, supposing that in each period the players bargain over how to play. Although the bargaining phase is cheap talk (following a generalized alternating-offer protocol), sharp predictions arise from three axioms. Two axioms allow the players to meaningfully discuss whether to deviate from their plan; the third embodies a “theory of disagreement”—that play under disagreement should not vary with the manner in which bargaining broke down. Equilibria satisfying these axioms exist for all discount factors and are simple to construct; all equilibria generate the same welfare. Optimal play under agreement generally requires suboptimal play under disagreement. Whether patient players attain efficiency depends on both the stage game and the bargaining protocol. The theory extends naturally to games with imperfect public monitoring and heterogeneous discount factors, and yields new insights into classic relational contracting questions.
Working paper 3/6/2013
Feb 06, 2013 Filed in: News
I am leaving UCSD to join the Economics Department
at the University of Michigan
, effective July 1, 2013. I will miss my San Diego colleagues very much, but I’m excited to work with the faculty and students at Michigan.
Jul 10, 2012 Filed in: News
For the 2012–2013 school year, I am visiting Microsoft Research New England
. I’m looking forward to lots of productive interactions with the permanent researchers, postdocs, and other visitors!
Apr 01, 2012 Filed in: Publications
Published in The Review of Economic Studies, 79(2):778–811, April 2012.
Abstract: The game-theoretic literature on collusion has been hard pressed to explain why a cartel should engage in price wars, without resorting to either impatience, symmetry restrictions, inability to communicate, or failure to optimize. This paper introduces a new explanation that relies on none of these assumptions: if the cartel's member firms have private information about their costs, price wars can be optimal in the face of complexity. Specifically, equilibria that are robust to payoff-irrelevant disruptions of the information environment generically cannot attain or approximate efficiency. An optimal robust equilibrium must allocate market shares inefficiently, and may call for price wars under certain conditions. For a two-firm cartel, cost interdependence is a sufficient condition for price wars to arise in an optimal robust equilibrium. That optimal equilibria are inefficient generically applies not only to collusion games, but also to the entire separable payoff environment (Chung & Ely 2006)—a class that includes most typical economic models.
Free-access link to published version
Sep 11, 2011 Filed in: Working papers
With Heidi Gjertsen, Theodore Groves, Eduard Niesten, Dale Squires, and Joel Watson
Abstract: We model conservation agreements using contractual equilibrium, a concept introduced by Miller and Watson (2010) to model dynamic relationships with renegotiation. The setting takes the form of a repeated principal-agent problem, where the principal must pay to observe a noisy signal of the agent's effort. Lacking a strong external enforcement system, the parties rely on self-enforcement for their relational contract. We characterize equilibrium play (including how punishments and rewards are structured) and we show how the parties' relative bargaining powers affect their ability to sustain cooperation over time. We argue that the model captures important features of real conservation agreements and reveals the ingredients required for successful agreements.
Working paper 9/23/2010 (stay tuned for an updated version in fall 2012)
Jul 29, 2011 Filed in: News
Nageeb Ali and I have been awarded a three-year grant from the National Science Foundation Economics Program, entitled “Enforcing Cooperation in Networked Societies.” Stay tuned for our first working paper soon (Update: now available), and lots of great projects to follow after that.
Abstract excerpt: The foundation of economic activity and growth is in the ability of individuals to trust and trade with each other over time. Throughout human history, much of economic activity occurs in realms where formal legal institutions are unwilling or unsuited to enforce cooperative behavior. A growing literature on informal enforcement suggests that the networked pattern of social relationships plays a key role in supporting cooperation: as information about past behavior diffuses through the network, an individual who deviates in a partnership is punished not only by her partner but also by those who come to learn about it. Our research program studies how communities enforce cooperation through their social networks.