Countercyclical taxes in a monopolistically competitive environment

In the context of a neoclassical growth model with monopolistic competition, this paper studies the stabilizing effects of countercyclical tax policy when the income tax rate has an additional role of financing government budget deficits. Consistent with the conventional wisdom, countercyclical taxes generally reduce aggregate volatility, unless the fiscal response to debt accumulation is weak. The presence of monopoly power enhances these effects. Even when automatic stabilizers successfully stabilize business cycle fluctuations, countercyclical taxes are welfare inferior, due to reduced precautionary saving motives. While, if the fiscal response to debt is weak and countercyclical tax policy destabilizing, the increased precautionary saving motive is not welfare enhancing as the asset accumulated is government debt rather than capital. These results are generally robust. Nominal inertia may, however, dominate the precautionary saving mechanism.     

Costly risk verification without commitment in competitive insurance markets

This paper analyzes the equilibrium of an insurance market where applicants for insurance have a duty of good faith when they reveal private information about their risk type. Insurers can, at some cost, verify the type of insureds who file a claim and they are allowed to retroactively void the insurance contract if it is established that the policyholder has misrepresented his risk when the contract was taken out. However, insurers cannot precommit to their risk verification strategy. The paper analyzes the relationship between second-best Pareto-optimality and the insurance market equilibrium in a game theoretic framework. It characterizes the contracts offered at equilibrium, the individuals' contract choice as well as the conditions under which an equilibrium exists.     

The efficiency of competitive equilibria in insurance markets with asymmetric information

This paper addresses the relationship between competitive equilibria and efficient allocations in an insurance market with asymmetric information. Using the definition of second-best efficiency proposed by Harris and Townsend (1981) for environments characterized by informational assmmetry, the efficiency properties of several proposed market equilibria are examined. We find an analogue to the First Optimality Theorem: A Miyazaki-Wilson equilibrium always results in a second best allocation.     

Union objectives and indexation externalities in a monopolistically competitive economy

This paper extends the literature on indexation externalities by analyzing equilibrium and efficient indexation in a unionized economy characterized by a monopolistically competitive goods market. The assumption that union objectives relate to both employment and the real wage implies that union indexation decisions are associated with a negative externality and, as a consequence, the equilibrium degree of indexation is inefficiently high. This feature is characteristic of both passive and activist policy environments.     

Heterogeneity of consumer preferences and trade patterns in a monopolistically competitive setting

The paper considers a two-sector two-country trade model of monopolistic competition featuring the heterogeneity of consumer preferences and incomes within and across countries. The incorporation of heterogeneity into a monopolistic competition setting is achieved by assuming a nested Cobb–Douglas and CES utility function exhibiting both country and sector-specific consumer tastes and expenditure shares on manufacturing and traditional goods. The key question analyzed in the paper is how consumer heterogeneity affects the home bias of trade in different countries. The key finding here is that the heterogeneity in tastes and incomes of consumers can provide a substantial influence on degree of home bias in trade but only in combination with high transportation costs.     

Information revelation in competitive markets

This paper analyzes a market with multiple sellers and horizontally differentiated products. We investigate the sellers’ incentives to reveal product relevant information that affects the buyer’s private valuation. The main finding is that if the number of sellers is sufficiently large, there is a unique symmetric equilibrium with full information disclosure. Thus, unlike the results by Lewis and Sappington (Int Econ Rev 35:309–327, 1994) and Johnson and Myatt (Am Econ Rev 93:756–784, 2006) for monopoly, which state that the monopolist reveals either full information or no information, intense competition results in a single extreme with respect to information disclosure. We show that the market is always inefficient, but the magnitude of inefficiency converges to zero at a high rate as competition intensifies.     

Regulating regulators in transitionally competitive markets

During the course of the first thirty CRRI conferences, we have gained considerable insight about how to design regulatory policy in the presence of developing competition. The insight to date has focused on how to harness competitive forces to motivate incumbent suppliers to serve the best interests of consumers. This paper stresses the importance of considering the incentives of regulators and explores the associated changes in standard recommendations for regulatory policy design in the presence of developing competition.     

Word-of-mouth reputations in auto insurance markets

A model is developed of the diffusion of information concerning stochastic quality levels of firms under assumptions of highly imperfect consumer knowledge. An equilibrium analysis finds that an increase in the rate of diffusion of information results in a decline in the elasticity of demand with respect to quality. A dynamic analysis indicates, however, that under certain conditions short-term elasticity increases with an increased rate of diffusion of information. The importance of dynamic analysis is underscored by the length of time often required for convergence to the steady state.     

Perfectly competitive markets as the limits of cournot markets

A perfectly competitive, partial equilibrium market for a single homogeneous good with a (bounded) continuum of infinitesimal firms is considered. Cost functions are essentially unrestricted and are allowed to vary smoothly across firms. A sequence (net) of Cournot markets (each with a finite number of firms) which converge smoothly to the perfectly competitive limit in terms of both the inverse demand functions and the distributioon of firm technologies is introduced and it is shown that all markets sufficiently far along the sequence have a Cournot equilibrium and all the Cournot equilibria converge to the perfectly competitive equilibrium of the limit market.     

The efficiency of monopolistically competitive equilibria in large economies: Commodity differentiation with gross substitutes

A general model of commodity differentiation is developed using two different approaches to the theory of demand. It is shown that a local version of Bertrand's argument holds under reasonable conditions. If all commodities are sustitutes and sunk costs are small, there is never too little commodity differentiation relative to the optimum. Under the same conditions, monopolistically competitive equilibria are approximately perfectly competitive if the optimal collection of commodities is sufficiently rich.     

在国际工程市场如何选择保险经纪

工程保险的险种、投保程序、保单内容等十分复杂,不仅需要耗费承包商大量的精力,而且不易得到优惠的保险条件和价格。虽然现在很多中国承包商已经意识到保险在工程风险管理中的重要地位,但在保险索赔中仍然会遇到很多困难。本文作者建议承包商采用国际通行的办法,即聘请保险经纪或保险咨询公司做顾问来解决上述问题。     

Regulation and efficiency in European insurance markets

With a series of directives completed in 1994 the European Commission tried to open and harmonize national European insurance markets. This has led to considerable deregulation in several countries. This paper surveys pre-1994 regulation in Germany and the UK and the Commission's policy. It argues that it is unlikely that the policy will have a significant impact on direct international competition between European insurance markets, until there is standardization of insurance law. However, the tightly regulated markets will become more like the loosely regulated UK market. The paper evaluates this outcome and concludes that the European Commission's policy may thereby have improved the welfare of insurance buyers in the previously highly regulated countries such as Germany. The paper also uses efficiency-frontier estimation to compare the dispersion of firm efficiencies in the German and British life insurance market. The results support the hypothesis that tighter solvency regulation allows the survival of a larger proportion of higher-cost firms.     

Non-discriminating renegotiation in a competitive insurance market

A variant of the Rothschild-Stiglitz model of a competitive insurance market is considered, where each uninformed firm is allowed to renegotiate the contracts that its customers initially sign, subject to the restriction that renegotiated contracts be offered to all the firm's customers. Such non-discriminating renegotiation is shown to weaken the profitability of cream skimming to the extent that there exists a unique equilibrium outcome. This outcome is that of Miyazaki and Spence i.e., the incentive-compatible pair of zero-profit contracts, if efficient; and the incentive-compatible, zero-profit pair of contracts maximizing low-risk utility, otherwise.     

Paradoxical price effects on insurance markets

In this paper we analyze a paradox phenomenon in certain insurance markets of some countries: in spite of there being strong competition, increasing prices can be found in some submarkets. As a reason for this, we need to note the special distribution of insurance products, a distribution primarily based on intermediaries — and, as a result, there is an increasing part for ‘intermediation’ costs within insurance products' cost structure due to competition for the intermediaries. We build an oligopolistic model assuming that the market is saturated, which is able to explain the overemployment of intermediaries and the high commissions involved. We analyze possible interventions and laws/regulations and suggest that the problem can be solved only with major regulation. Finally, we have come up with an empirical analysis to test the model.     

Equilibria in incomplete assets economies with infinite dimensional spot markets

The paper studies the two period incomplete markets model where assets are claims on state contingent commodity bundles and there are no bounds on portfolio trading. The important results on the existence of equilibrium in this model assume that there is a finite number of commodities traded in each spot market and that preferences are given by smooth utility functions. With these assumptions an equilibrium exists outside an “exceptional” set of assets structures and initial endowments. The present paper extends these results by allowing for general infinite dimensional commodity spaces in each spot market. These include all the important commodity spaces studied in the literature on the existence of Walrasian equilibrium—in each spot market the consumption sets are the positive cone of an arbitrary locally solid Riesz space or of an ordered topological vector space with order unit or of a locally solid Riesz space with quasi-interior point. The paper establishes that even with our very general commodity spaces there exists an equilibrium for a “very” dense set of assets structures. Our approach is in the main convex analytic and the results do not require that preferences be smooth or complete or transitive. The concepts and techniques studied in this paper have important finite as well as infinite dimensional applications. This paper has benefited from the comments of Martine Quinzii, Wayne Shafer, Manuel Santos and Yeneng Sun. The research of C. D. Aliprantis is supported by the NSF Grants SES-0128039, DMS-0437210, and ACI-0325846. The research of R. Tourky is funded by the Australian Research Council Grant A00103450.     

Price regulation in insurance markets with asymmetric information

The paper presents and discusses a regulatory policy in insurance markets. It is based upon a two-sided rule: each company must propose at least one contract with full coverage and a ceiling is imposed on the level of premiums.     

Equilibria and Pareto optima of markets with adverse selection

Summary This paper examines the efficiency properties of competitive equilibrium in an economy with adverse selection. The agents (firms and households) in this economy exchange contracts, which specify all the relevant aspects of their interaction. Markets are assumed to be complete, in the sense that all possible contracts can, in principle, be traded. Since prices are specified as part of the contract, they cannot be used as free parameters to equate supply and demand in the market for the contract. Instead, equilibrium is achieved by adjusting the probability of trade. If the contract space is sufficiently rich, it can be shown that rationing will not be observed in equilibrium. A further refinement of equilibrium is proposed, restricting agents' beliefs about contracts that are not traded in equilibrium. Incentive-efficient and constrained incentive-efficient allocations are defined to be solutions to appropriately specified mechanism design problems. Constrained incentive efficiency is an artificial construction, obtained by adding the constraint that all contracts yield the same rate of return to firms. Using this notion, analogues of the fundamental theorems of welfare economics can be proved: all refined equilibria are constrained incentive-efficient and all constrained incentive-efficient allocations satisfying some additional conditions can be decentralized as refined equilibria. A constrained incentive-efficient equilibrium is typically not incentive-efficient, however. The source of the inefficiency is the equilibrium condition that forces all firms to earn the same rate of return on each contract.Notation ={ ₁,..., _k } set of outcomes - : ₊ generic contract or lottery - A = () ; - A_o A{, where denotes the null contract or no trade - S={1,...,¦S¦} set of seller types - L(s) number of type-s sellers - M number of buyers - u: × S seller's utility function, which can be extended toA× S by puttingu(, s) ; - v. × S buyer's utility function, which can be extended toA × S by puttingv(, s) ; - f:A ₀ ×S ₊ allocation of sellers - g:A ₀ ×S ₊ allocation of buyers - A ₊ sellers' trading function - :A ×S ₊ buyers' trading function This paper has had a long gestation period, during which I have been influenced by helpful conversations with many persons, by their work, or both. Among those who deserve special mention are Martin Hellwig, Roger Myerson, Edward Prescott, Robert Townsend and Yves Younés. Earlier versions were presented to the NBER/CEME Conference on Decentralization at the University of Toronto and the NBER Conference on General Equilibrium at Brown University. I would like to thank John Geanakoplos, Walter Heller, Andreu Mas Colell, Michael Peters, Michel Poitevin, Lloyd Shapley, John Wooders, Nicholas Yannelis and an anonymous referee for their helpful comments and especially Robert Rosenthal for his careful reading of two drafts. The financial support of the National Science Foundation under Grant No. 912202 is gratefully acknowledged.     

The optimal insurance contract in a competitive market

The author reviews some earlier work on optimal insurance contracts by Arrow and Mossin. He then shows that some results in this work carry over to any premium system which satisfies the additivity condition inherent in a competitive market.