Quality Competition and Social Welfare in Markets with Partial Coverage: New Results*

We use a vertical product differentiation model under partial market coverage to study the social welfare optimum and duopoly equilibrium when convex costs of quality provision are either fixed or variable in terms of production. We show the following new results. First, under fixed costs, the social planner charges a uniform price for the single variant that just covers costs of quality provision. Like the duopoly equilibrium, this socially optimal pricing entails a partially uncovered market, but a smaller share of the market is served compared with the duopoly equilibrium. Second, for the variable cost case, it is socially optimal to provide both high‐ and low‐quality variants, but market shares need not be equal. This differs from the result in fully covered markets. Third, in the duopoly equilibrium, the quality spread is too wide under variable costs relative to the social optimum. Under fixed costs, the duopoly produces two variants, but quality is too low relative to the social optimum, which has only one variant.     

Does individualization help productivity of transition agriculture?

There are large differences across transition countries with respect to agricultural‐sector performance and corresponding scope of farm restructuring and shift to individual farming. In this article we analyze the impact of individualization on productivity growth within an augmented neoclassical growth model framework. This approach allows us to circumvent criticisms on the grounds of lack of theoretical and objective criteria for inclusion of explanatory variables. Furthermore, in the empirical analysis using a panel data covering 15 transition countries over the period 1990–2001 and applying a generalized method of moments with instrumental variable estimator we are able to control for the impact of various factors and the potential endogeneity of variables. Our estimation results are robust and support the view that the shift to individual farming, as well as the overall economic reforms, has positively contributed to the productivity growth in agriculture during the first decade of transition.     

构建农村和谐社会的思考

构建农村和谐社会,应当树立正确的农民增收观,促进农民持续快速增收,缩小城乡差别;加快农地产权制度改革,解决农地矛盾和纠纷;加快农村基层组织制度和县乡行政改革,解决农村干群矛盾;加快农村教育发展,改进农村教育质量,提高农民素质;加大再造秀美山川工程监管力度,消除工作中存在的不实、不公等因素;加快农村社会保障制度建设,消除农民的后顾之忧.     

Indonesian Local Government Spending,Taxing and Saving: An Explanation of Pre‐ and Post‐decentralization Fiscal Outcomes*

As a result of Indonesia's decentralization program, local governments have gained significantly more responsibility for service delivery, considerably larger fiscal resources, and much greater authority over the use of those resources than before. The present paper develops a simple budget model to describe and explain the substantial differences in pre‐ and post‐decentralization local government fiscal behavior related to spending, taxing and saving. During the post‐decentralization period special attention is paid to the fiscal behavior of natural resource rich regions. Among other things, the evidence suggests that: post‐decentralization local government spending is partly responsive to increasing needs and partly the subject of elite capture; local government taxation has become more aggressive under decentralization and appears to be mostly driven by local bureaucratic expectations related to routine overhead budgets; and the increased savings of local governments during the post‐decentralization period is determined to a large degree by delayed central government transfer payments.     

Partial Horizontal Inequity Orderings: A Non‐parametric Approach*

We provide a partial ordering view of horizontal inequity (HI), based on the Lorenz criterion, associated with different post‐tax income distributions and a (bistochastic) non‐parametric estimated benchmark distribution. As a consequence, several measures consistent with the Lorenz criterion can be rationalized. In addition, we establish the so‐called HI transfer principle, which imposes a normative minimum requirement that any HI measure must satisfy. Our proposed HI ordering is consistent with this principle. Moreover, we adopt a cardinal view to decompose the total effect of a tax system into a welfare gain caused by HI‐free income redistribution and a welfare loss caused by HI, without any additive decomposable restriction on the indices. Hence, more robust tests can be applied. Other decompositions in the literature are seen as particular cases.     

Heterogeneity and Share Contracting in Medical Group Practices

This paper offers an empirical analysis of the relationship between income sharing rules and physician heterogeneity in medical group practices.The economies to group formation associated with risk–sharing, mutual monitoring,and internal referral are served by sharing at least a portion of group income equally. Sharing group income equally is problematic, however, when group members differ in their contribution to group income. Member contributions to group income may differ because of differences in ability, effort, or the price of services across specialty fields. The analysis below is addressed to the question of how income sharing rules in physician groups are affected by variation in member contributions. The analysis finds evidence that heterogeneity in member contributions to group income limits the use of equal income sharing rules in multispecialty groups relative to single specialty groups, and large groups relative to small groups. Nevertheless, 65% of all groups in the survey share at least a pn of group income equally, which broadly suggests that the joint surplus enhancement from risk sharing, mutual monitoring, and internal referral are sufficient to overcome the incentive problems of such rules     

R&D项目投资评估的实物期权方法初探

本文分析了传统的NPV法在R&D项目投资评估中的缺陷,指出R&D项目投资本质上所具有的期权特性。在此基础上引入了实物期权方法,包括Black-Scholes期权定价方法和Geske期权定价模型。     

Income distribution and inequality measurement: The problem of extreme values

We examine the statistical performance of inequality indices in the presence of extreme values in the data and show that these indices are very sensitive to the properties of the income distribution. Estimation and inference can be dramatically affected, especially when the tail of the income distribution is heavy, even when standard bootstrap methods are employed. However, use of appropriate semiparametric methods for modelling the upper tail can greatly improve the performance of even those inequality indices that are normally considered particularly sensitive to extreme values.     

Hölder continuity of the policy function approximation in the value function approximation

We show that given a value function approximation V of a strongly concave stochastic dynamic programming problem (SDDP), the associated policy function approximation is Hölder continuous in V.