A simple random assignment problem with a unique solution

Summary. All agents have the same ordinal ranking over all objects, receiving no object (opting out) may be preferable to some objects, agents differ on which objects are worse than opting out, and the latter information is private. The Probabilistic Serial assignment, improves upon (in the Pareto sense) the Random Priority assignment, that randomly orders the agents and offers them successively the most valuable remaining object. We characterize Probabilistic Serial by efficiency in an ordinal sense, and envy-freeness. We characterize it also by ordinal efficiency, strategyproofness and equal treatment of equals. Received: October 5, 1999; revised version: December 20, 2000     

Tuition fees and social segregation: lessons from a natural experiment at the University of Paris 9-Dauphine

Using a natural experiment, a sharp rise in tuition fees in some of the programmes at the University of Paris 9-Dauphine, we study the impact of tuition fees on students’ pathways, and outcomes. We apply an optimal matching method to the national database of students’ registrations (SISE) to define a typology of pathways. We then use a nonordered multinomial logit model to evaluate the impact of the rise in tuition fees on the types of pathways selected by the university. We show that there is a significant impact on these pathways. The increase in tuition fees reduces geographic and social mobility, thereby accentuating the phenomena of social segregation. Furthermore, contrary to what some of the studies assert, the rise does not appear to encourage greater effort: we find no impact on the graduation success rate.     

Thoughts,attitudes and profile of Brazilian consumers regarding food irradiation

This study aimed to examine the neophobia, knowledge, thoughts, and opinions related to food irradiation among consumers living in a small city in Brazil through the application of a behavioral and sociodemographic questionnaire. It was found that the 271 respondents had little knowledge about the process of food irradiation and had low intent to purchase irradiated food; several consumers associated irradiated food with radioactivity and cancer. Individuals with better knowledge about irradiation and those who are young, single, did not live with children, and had higher levels of education and higher monthly family incomes were more likely to buy irradiated foods than others. These results describe the profile of potential consumers of irradiated foods and the knowledge, thoughts and opinions of the residents of a small city relative to food irradiation. This data could assist industries that irradiate foods to adopt strategies that ensure greater acceptance of their products.     

Distributive and Additive Costsharing of an Homogeneous Good

Individual users demand different quantities of a homogeneous good produced under variable returns. We describe the family of costsharing methods that allocate costs in proportion to demands when returns are constant, and commute with the additivity and composition of cost functions. Two simple such methods are average cost pricing and incremental costsharing. All other methods in the family combine elements of the average cost and incremental ones. Serial costsharing stands out prominently in the family, whereas the Shapley–Shubik method, and all values from the associated stand alone cooperative game, are excluded.Journal of Economic LiteratureClassification Numbers: D63, C71.     

澳大利亚电力期货市场的形成与发展

本文通过对澳大利亚电力市场化改革方向的梳理,揭示了电力期货市场的形成和发展过程.其主要路径是:(1)从电力垄断到电力市场化改革,建立电力现货市场;(2)在电力现货市场运行中暴露出电价剧烈波动的问题,引入电力远期合约;(3)电力远期合约出现市场参与不足和流动性差的问题,电力期货市场应运而生.事实证明,澳大利亚电力现货和期货市场并存,但期货市场在提高市场参与度、流动性、安全性以及稳定和发现电价方面的作用更大.本研究通过展示澳大利亚电力期货市场建立过程中的风险和问题,为中国电力市场化改革提供参考.     

Commons with increasing marginal costs: random priority versus average cost*

Indivisible units are produced with increasing marginal costs. Under average cost, each user pays average cost. Under random priority, users are randomly ordered (without bias) and successively offered to buy at the true marginal cost. Both average cost (AC) and random priority (RP) inefficiently overproduce. RP tends to overproduce less, but which game collects more surplus depends much on the demand configuration. We show that a key to compare the welfare properties of the two mechanisms is the crowding factor, i.e., the number of potential users over the number of units of output users can afford: The more crowded the commons, the more RP outperforms AC. In the quadratic cost case, beyond the threshold value of 2.4 for the crowding factor, RP strongly outperforms AC; beneath it AC only mildly outperforms RP. Thus the RP mechanism manages crowded commons better than AC.     

Pro‐competitive Effect of Trade and Non‐decreasing Price‐Cost Margins*

This study surveys the empirical evidence on the pro‐competitive effect of international trade and analyses the determinants of price‐cost margins for OECD countries between 1970 and 2003. The main objective was to focus on the quantification of the impact of imports on margins, and understand why, despite trade liberalization, price‐cost margins have not fallen overall. On average, imports would have contributed to a large decrease of five percentage points in the price‐cost margins. However, these effects seem to have been partially counterbalanced by the impacts of financial deepening and disinflation.     

Decentralized pricing in minimum cost spanning trees

In the minimum cost spanning tree model we consider decentralized pricing rules, i.e., rules that cover at least the efficient cost while the price charged to each user only depends upon his own connection costs. We define a canonical pricing rule and provide two axiomatic characterizations. First, the canonical pricing rule is the smallest among those that improve upon the Stand Alone bound, and are either superadditive or piece-wise linear in connection costs. Our second, direct characterization relies on two simple properties highlighting the special role of the source cost.     

账户操纵——文献回顾及关于概念框架的设想

公司操纵账户的做法由来已久。此类行为在研究文献中常被提及，并被赋予各种名称，如盈余管理、利润平滑化、除垢会计、创造性会计和账户粉饰等。本文将对相关文献做一个综合性回顾，并就账户操纵问题提出一个概念性框架。