Unmediated communication in games with complete and incomplete information

We study the effects of adding unmediated communication to static, finite games of complete and incomplete information. We characterize S^U(G), the set of outcomes of a game G, that are induced by sequential equilibria of cheap talk extensions. A cheap talk extension of G is an extensive-form game in which players communicate before playing G. A reliable mediator is not available and players exchange private or public messages that do not affect directly their payoffs. We first show that if G is a game of complete information with five or more players and rational parameters, then S^U(G) coincides with the set of correlated equilibria of G. Next, we demonstrate that if G is a game of incomplete information with at least five players, rational parameters and full support (i.e., all profiles of types have positive probability), then S^U(G) is equal to the set of communication equilibria of G.     

Herding in delegated portfolio management: When is comparative performance information desirable?

We address the issue of investors’ asset allocation decisions when portfolio management is delegated to an agent. Contrary to predictions from traditional financial theory, it is shown that investors may not induce their manager to allocate funds to the asset with the highest return. Instead they may herd in their asset allocation decision and induce trade in a particular asset, because another manager is trading in it and despite the presence of a more profitable alternative. Doing so allows investors to write an efficiency-improving relative-performance contract. On the other hand, herding leads investors to design wage contracts strategically, resulting in more aggressive and thus less profitable trade in equilibrium. We show that herding occurs, when the cost of information is high, information precision is low and when managers are sufficiently risk averse. Moreover, when investors can decide whether or not to disclose information about their manager's performance, they will not do so.     

第三方逆向物流信息系统分析与设计

指出信息系统在第三方逆向物流企业中的重要性,分析了第三方逆向物流企业的业务流程和数据传输流程,并提出设计C/S与B/S相混合的第三方逆向物流信息系统的设计方案,并进一步探索了如何通过ASP.NET技术来实现。     

Self-control in peer groups

Social influences on self-control underlie both self-help groups and many peer interactions among youths. To understand these phenomena, we analyze how observing each other's behavior affects individuals’ ability to deal with their own impulses. These endogenous informational spillovers lead to either a unique “good news” equilibrium that ameliorates behavior, a unique “bad news equilibrium” that worsens it, or to the coexistence of both. A welfare analysis shows that people will find social interactions valuable only when they have enough confidence in their own and others’ ability to resist temptation. The ideal partner, however, is someone with a slightly worse self-control problem than one's own: this makes his successes more encouraging, and his failures less discouraging.     

Market games with differential information and infinite dimensional commodity spaces: The core

Summary We provide an alternative proof of the existence of core allocations in exchange economies with differential information and infinite dimensional commodity spaces. We also identify a critical feature of information sharing rules that ensures nonemptiness of the core. In essence, the only condition we require on the sharing rules is that profitable insider trading be prohibited. In the absence of insider trading, balancedness is guaranteed and core nonemptiness follows.I thank Dan Arce, Erik Balder, Myrna Wooders, and Nicholas Yannelis for helpful comments. This paper is a greatly revised version of my paper entitled. A Variational Problem Arising in Market Games with Differential Information, written in August of 1991.     

Corrigendum to “When is efficiency separable from distribution in the provision of club goods?” [Journal of Economic Theory 90 (2000) 204-221]

This note corrects a slip in Fraser's (J. Econ. Theory 90 (2000) 204-221) treatment of the necessary condition for partial separation of efficiency from distribution in providing a club good. His corrected Theorem 1 shows that many families of utility function can generate partial (and total) separation, thereby considerably extending the scope of his analysis.     

A complete characterization of Pareto optimality for general OLG economies

In the context of general pure exchange OLG economies where agents can have heterogeneous longevities, we provide both sufficient and necessary conditions for Pareto optimality of competitive equilibria. For the case in which all agents live for the same number of periods, we find that these conditions are equivalent. We also find this equivalence when agents can have different lifetimes, but in this case we need to impose particular restrictions on relative equilibrium prices. Moreover, we show that without these conditions on prices the equivalence, and hence a full characterization, is not necessarily obtained.     

Timing and Commitment of Environmental Policy,Adoption of New Technology,and Repercussions on R&;D

We investigate the interplay between environmental policy, incentives to adoptnew technology, and repercussions on R&D. We study a model where a monopolistic upstream firm engages in R&D and sells advanced abatement technology to polluting downstream firms. We consider four different timing and commitment regimes of environmental tax and permit policies: ex post taxation (or issuing permits), interim commitment to a tax rate (a quota of permits) after observing R&D success but before adoption, and finally two types of ex antecommitment before R&D activity, one with a unique tax rate (quota of permits), the other one with a menu of tax rates (permit quotas). We study the second best tax and permit policies and rank these with respect to welfare. In particular, we find that commitment to a menu of tax rate dominates all other policy regimes.     

Price and quantity regulation in general equilibrium

We consider a general equilibrium model with a production externality (e.g. pollution), where the regulator does not observe firm productivity shocks. We examine quantity (permit) regulation and price (tax) regulation. The quantity of permits issued by the regulator are independent of the productivity shock, since shocks are unobserved. Price regulation implies use of the regulated input is an increasing function of the productivity shock because firms take advantage of a good productivity shock by increasing input use. Thus price regulation generates higher average, but more variable, production. Therefore, we show that in general equilibrium the relative advantage of quantity versus price regulation depends not only on the slopes of marginal benefits and costs, but on general equilibrium effects such as risk aversion. The general equilibrium effects are often more important than the slopes of the marginal benefits and cost curves. In the simplest model, a reasonable risk aversion coefficient implies quantity regulation generates higher welfare regardless of the benefit function.     

Modelling cost complementarities in terms of joint production

Cost complementarities arise from synergies in the production of heterogeneous goods. It is shown that synergies can be accounted for in terms of shared public inputs (roughly) if and only if synergies decrease as the scope of production increases. This case of “substitutive” synergies is argued to be typical. The key technical tool is a novel interpretation of conjugate Moebius inversion in terms of higher-order differences.