The equilibrium set of two-player games with complementarities is a sublattice

Summary. I prove that the equilibrium set in a two-player game with complementarities, and totally ordered strategy spaces, is a sublattice of the joint strategy space. Received: May 31, 2001; revised version: October 4, 2002     

The proper panel econometric specification of the gravity equation: A three-way model with bilateral interaction effects

We argue that the proper specification of a panel gravity model should include main (exporter, importer, and time) as well as time invariant exporter-by-importer (bilateral) interaction effects. In a panel of 11 APEC countries, the latter are highly significant and account for the largest part of variation. First version received: February 2001/Final version received: June 2002 RID="*" ID="*"  We are grateful to two anonymous referees and Robert Kunst for their helpful comments.     

Class length and student performance: An extended study

Many accounting educators believe that the student learning of accounting is better facilitated over a longer period of time, rather than a shorter period of time. This study examined the results of student performance in two introductory accounting courses, comparing student performance results of four-week summer classes with the results of traditional 16-week courses. In this research, the same professor taught the spring and summer ACC 201 courses, and two other professors taught both the spring and summer ACC 211 courses. Also held constant were the lecture material, course assignment, and test content. The results of the study indicate that in general, students taking introductory accounting over four weeks fare about as well as students who take introductory accounting over a traditional 16-week period. These results have potential importance beyond accounting education and provide support to universities offering more block courses to better serve individual student needs.     

Double Moral Hazard,Monitoring, and the Nature of Contracts

generalized double-sided moral-hazard model, with risk-averse parties who mutually monitor each other (to get a reasonable idea of outcome/effort). The model considers trade-off between monitoring costs and moral hazard costs, which are endogenously determined by the extent of monitoring. Using this model, we formally prove a generalized version of Coase's conjecture – that the optimal contract minimizes the agency and risk costs. We then show how varying assumptions about the feasibility or cost of monitoring of the outcome or the worker's effort lead to different contracts being optimal. The analysis is then used to explain the nature of contracts observed in practice under many different situations. We will give an explanation as to why industrial workers typically work under wage contracts, while share contracts are common in agriculture and will explain why profit sharing is more common for senior managers than for the production workers. Received September 19, 2000; revised version received October 30, 1997     

The impact of product diversification strategy on the corporate performance of large Spanish firms

We analyze the impact of product diversification on performance. This topic has been discussed in the literature, and there is no consensus so far as to the significance or the direction of the impact. Performance is measured using Tobin's q for a sample of 103 large, non-financial Spanish firms (1992–1995). Diversification is measured by means of a categorical variable, as suggested by Varadarajan. The principal results indicate that the firms with intermediate levels of product diversification have the highest performance, while the firms with low and high levels of diversification show significantly lower performance, which performance is not significantly different between them.     

Corporate Lobbying, Regulatory Conduct and the Porter Hypothesis

Michael Porter, the influential Harvard management guru, has promoted the idea that compliance with stricter environmental regulations can afford secondary benefits to firms through improved product design, innovation, corporate morale and in other ways. Once these secondary benefits are factored, the net cost of compliance is argued to be lower than conventionally thought and may even be negative. Whilst environmental economists have rejected the Porter Hypothesis as being based on excessively optimistic expectations of the likely size of such secondary benefits the underlying ideas do enjoy significant credence in the business community. In the context of a lobbying model of regulatory policy-making we argue that the EPA should change the way it conducts regulatory policy to take account of Porter's views – even if it knows those views to be misguided. The model serves to illustrate the more general point that fashions in management thinking can be expected to impact the optimal conduct of regulatory policy.     

房地产价格风险：国际教训、中国的现状及路径选择

房地产泡沫会增加金融风险,房价大幅缩水会导致银行破产,股市下跌。日本、美国、英国、泰国等都爆发过与房地产相关的银行危机。目前,中国房地产金融具有市场风险、财务风险、道德风险和信用风险等潜在风险。应利用税收手段限制投机性购房和短期炒作行为,鼓励中小户型住房的消费,加强城镇廉租住房制度建设,防范“假按揭”风险,完善惩戒机制,加强利率风险管理,完善住房置业担保制度,进一步研究制定房贷保险制度。     

Selecting Social Goals: J. M. Keynes and the Emergence of Ontological Rationality in Economics

In this paper we discuss the fundamental inconsistency that results from employing the two traditional concepts of rationality as the basis of selecting social goals. We then consider the possibility that the selection of social goals must be based on explicitly ethical criteria. To do so a third concept of rationality namely, ontological rationality, should be adopted. Moreover, we argue that J. M. Keynes in A Tract Monetary Reform based his public policy recommendations on a modified version of ontological rationality, thereby introducing ontological rationality into economics as the basis for selecting social goals.A previous version of this paper was presented at the Fifty-Eighth International Atlantic Economic Conference, October 7–10, 2004. The authors are grateful to session participants for their helpful suggestions, though the authors alone are responsible for the contents of the paper.     

Environmental Product Differentiation and Environmental Awareness

In this paper, we have considered a duopolistic model of environmental product differentiation with two types of consumers (green and brown) to analyze how environmental awareness affects the environment. “Green” consumers value the physical and environmental attributes of the good they purchase while “brown” consumers only value the physical attributes. We find that more environmental awareness may not be good news for the environment as the firm that produces the good without environmental attributes may increase its sales. The result depends on the degree of product differentiation and the cost to achieve it. Social welfare can also be inversely related to environmental awareness if the negative environmental effect dominates the positive market effect.