演講者簡介 : John K.-H. Quah received his Ph.D. in Economics from University of California at Berkeley in 1994. He is currently serving as Professor of Economic Theory at Oxford University. His research field is in consumer demand, general equilibrium, comparative statics, and supermodular games.
演講摘要 : The single crossing property plays a crucial role in economic theory, yet there are important instances where the property cannot be directly assumed or easily derived. Difficulties often arise because the property cannot be aggregated: the sum or convex combination of two functions with the single crossing property need not have that property. We introduce a new condition characterizing when the single crossing property is stable under aggregation and also identify sufficient conditions for the preservation of the single crossing property under multidimensional aggregation. We use our results to establish properties of objective functions (convexity, logsupermodularity), the monotonicity of optimal decisions under uncertainty, and the existence of monotone equilibria in Bayesian-games.
