Other

Other papers (without abstracts)

“Ratifiable Mechanisms: Learning from Disagreement,” (with Thomas R. Palfrey) Games and Economic Behavior, 10, 255–283, 1995.

“Cartel Enforcement with Uncertainty About Costs,” (with Thomas R. Palfrey) International Economic Review, 31, 17–47, 1990. Reprinted in Stephen W. Salant and Margaret C. Levenstein (eds.), Cartels, Volume 1, Cheltenham, UK: Edward Elgar, 2005.

“Nonrandom Mixing Models of HIV Transmission,” (with Edward Kaplan, and A. David Paltiel) in Mathematical and Statistical Approaches to AIDS Epidemiology, edited by Carlos Castillo-Chávez, Lecture Notes in Biomathematics Series, Springer-Verlag, 218–239, 1989.


Other papers (with abstracts)

“Ratifiable Mechanisms: Learning from Disagreement,” (with Thomas R. Palfrey) Games and Economic Behavior, 10, 255–283, 1995.

In a mechanism design problem, participation constraints require that all types prefer the proposed mechanism to some status quo. If equilibrium play in the status quo mechanism depends on the players’ beliefs, then the inference drawn if someone objects to the proposed mechanism may alter the participation constraints. We investigate this issue by modeling the mechanism design problem as a two-stage process, consisting of a ratification stage followed by the actual play of the chosen game. We develop and illustrate a new concept, ratifiability, that takes account of inferences from a veto in a consistent way.

“Cartel Enforcement with Uncertainty About Costs,” (with Thomas R. Palfrey) International Economic Review, 31, 17–47, 1990. Reprinted in Stephen W. Salant and Margaret C. Levenstein (eds.), Cartels, Volume 1, Cheltenham, UK: Edward Elgar, 2005.

What cartel agreements are possible when firms have private information about production costs? For private cost uncertainty we characterize the set of cartel agreements that can be supported, recognizing incentive and participation constraints. If defection results in either Cournot or Bertrand competition, the incentive problem in large cartels is severe enough to prevent the cartel from achieving the monopoly outcome. However, if the cartel agreement requires less than unanimous ratification by the member firms, then the incentive problem can be overcome in large cartels. With common cost uncertainty, perfect collusion is possible in large cartels, regardless of the ratification rule.

“Nonrandom Mixing Models of HIV Transmission,” (with Edward Kaplan, and A. David Paltiel) in Mathematical and Statistical Approaches to AIDS Epidemiology, edited by Carlos Castillo-Chávez, Lecture Notes in Biomathematics Series, Springer-Verlag, 218–239, 1989.

Models of HIV transmission and the AIDS epidemic generally assume random mixing among those infected with HIV and those who are not. For sexually transmitted HIV, this implies that individuals select sex partners without regard to attributes such as familiarity, attractiveness, or risk of infection. This paper formulates a model for examining the impact of nonrandom mixing on HIV transmission. We present threshold conditions that determine when HIV epidemics can occur within the framework of this model. Nonrandom mixing is introduced by assuming that sexually active individuals select sex partners to minimize the risk of infection. In addition to variability in risky sex rates, some versions of our model allow for error (or noise) in information exchanged between prospective partners. We investigate several models including random partner selection (or proportionate mixing), segregation of the population by risky sex rates, a probabilistic combination of segregation and random selection induced by imperfect information (or preferred mixing), and a model of costly search with perfect information. We develop examples which show that nonrandom mixing can lead to epidemics that are more severe or less severe than random mixing. For reasonable parameter choices describing the AIDS epidemic, however, the results suggest that random mixing models overstate the number of HIV infections that will occur.