A generalization of Condorcet’s Jury Theorem to weighted voting games with many small voters

We extend Condorcet’s Jury Theorem (Essai sur l’application de l’analyse à la probabilité des décisions rendues à la pluralité des voix. De l’imprimerie royale, 1785) to weighted voting games with voters of two kinds: a fixed (possibly empty) set of ‘major’ voters with fixed weights, and an ever-increasing number of ‘minor’ voters, whose total weight is also fixed, but where each individual’s weight becomes negligible. As our main result, we obtain the limiting probability that the jury will arrive at the correct decision as a function of the competence of the few major players. As in Condorcet’s result the quota q = 1/2 is found to play a prominent role. I wish to thank Maurice Koster, Moshé Machover, Guillermo Owen and two anonymous referees for helpful comments.     

Background Risk and the Performance of Insurance Markets under Adverse Selection

Background risk can influence the performance of insurance markets that must deal with adverse selection when applicants are risk vulnerable, since they are more averse to bearing the insurable risk as a result of their exposures to background risk. We show that background risk always results in a lower deductible for the incentive constrained contract, and that a broader range of markets attains the stable sequential equilibrium cross-subsidized pair of separating contracts. We conclude that background risk always improves the performance of markets for coverage against (insurable) foreground risks that must deal with adverse selection. We also find, however, that these improvements are never sufficient to offset the cost to insureds of bearing the background risk.     

中国货币政策紧缩 到底有多紧？

[英国路透社3月18日]中国反复重申，转向“紧缩”货币政策，取代之前“适度从紧”政策，以抑制创下10年新高的通货膨胀。     

Speculative attack against the Hungarian forint

In mid-January 2003 a severe speculative attack was launched against the exchange rate of the Hungarian forint. The attack was very unusual in the history of foreign exchange speculations, since it was aimed at enforcing the appreciation — and not the depreciation — of the currency targeted. The specific nature of this kind of speculation is closely related to Hungary’s accession to the European Union in general and to EMU in particular. Since the other Central and Eastern European acceding countries face similar problems and challenges, the Hungarian experience may involve some instructive lessons on monetary and economic policy for them too.