How many voters are needed for paradoxes?

Summary. This paper presents a general procedure for finding profiles with the minimum number of voters required for many important paradoxes. Borda's and Condorcet's classic examples are revisited as well as generalizations. Using Saari's procedure line, we obtain an upper bound for the minimum number of voters needed for a profile for which the Condorcet winner is not strictly top ranked for all weighted positional procedures. Also we give a simple upper bound on the minimum number of voters needed for a set of prescribed voting outcomes. In contrast to situations wherein small numbers of voters are needed, we consider paradoxes requiring arbitrarily large numbers of voters as well as large numbers of alternatives. Finally we indicate connections with statistical rank based tests. Received: April 18, 2001; revised version: May 25, 2001     

On the evolutionary edge of altruism: a game-theoretic proof of Hamilton’s rule for a simple case of siblings

We offer a game-theoretic proof of Hamiltons rule for the spread of altruism. For a simple case of siblings, we show that the rule can be derived as the outcome of a one-shot prisoners dilemma game between siblings.JEL Classification: A13, C70, D64Correspondence to: Oded Stark, ZEF, University of Bonn, Walter-Flex-Strasse 3, 53113 Bonn, GermanyWe are indebted to an anonymous referee and to Uwe Cantner for helpful comments and suggestions. Partial financial support from the National Institute on Aging (grant RO1-AG13037) and from the Humboldt Foundation is gratefully acknowledged.     

On transaction efficiency and China’s Urban-Rural disparity

It is recommended for economists to examine China’s Urban-Rural disparity from the perspective of transaction efficiency, in that it can provide us with a systematic explanation to both the cases of different countries and development stages. China’s Urban-Rural disparity is special and virtually a demonstration of its special transaction efficiency structure. Exploration of China’s Urban-Rural disparity from such perspective indicates that, different from those in countries with a market economy, China’s case involves many exogenous and contrived factors. Therefore, the solutions are to improve the whole transaction efficiency in the economy, which includes eliminating its regionally unfavorable policies and institutions, and enforcing more favorable and regionally balanced institutional reforms. __________ Translated from Fudan Journal (复旦学报, Social Science Edition), 2006, (1) (in Chinese)     

控制权性质影响税收敏感性吗?——基于企业劳动力需求的检验

西方学者研究表明企业所得税是劳动力需求的重要影响因素,这一理论在中国是否适用?中国大部分上市公司为国有控股企业,这一特殊的制度背景是否会影响企业所得税与劳动力需求的关系?本文基于2007年企业所得税改革这一外生政策变化,在检验西方企业所得税与劳动力需求关系的理论在中国是否适用的基础上,就不同控制权的性质是否会影响企业劳动力需求的税收敏感性进行了检验。研究发现企业所得税税率降低和"就业税盾"增加提高了企业劳动力需求,但这种税率和"就业税盾"的变化对国有控股企业劳动力需求变化的影响要显著小于非国有控股企业。这表明税收是影响企业劳动力需求的重要因素,但国有控制权使得这种税收敏感性变弱。本文的研究结果不仅丰富了相关领域的国际学术文献,而且对我国就业政策的制定具有政策含义。     

论企业文化在塑造核心竞争力诸因素中的核心地位

本文借鉴7S模型分析了塑造企业核心竞争力的影响因素和途径,运用文献和案例论证了企业文化在塑造核心竞争力的各因素中居于核心地位,指出了塑造核心竞争力的途径是运用先进的企业文化培育和谐的7S体系。     

由临街地价推算区片价的方法探讨

如何利用临街样点地价推算区片平均地价及基准地价始终是城镇基准地价评估的一个难点。文章利用赤峰市的实际调查数据,分别采用临街贡献率和面积加权两种方法推算区片平均地价,并采用回归分析方法探讨区片价与临街地价之间的关系,结果证明两种方法所推算的区片平均价是基本一致的,而且区片价与临街地价之间呈“反S”曲线关系。     

政策性农业保险推广对农民收入的增进效应与作用路径解析--对渐进性试点的准自然实验研究

政策性农业保险作为重要的支农政策工具之一,除了起到农业风险管理作用之外,从长期来看还具有促进农民增收等效应。本文通过对已有文献进行梳理,讨论了政策性农业保险推广对农民收入增加的作用路径,并基于准自然实验的思路,将我国各省开展政策性农业保险试点作为外生冲击,利用2000~2016年的省级数据,使用渐进性双重差分的方法,评估政策性农业保险推广对农村居民收入以及收入结构的长期影响效果。研究发现,政策性农业保险试点对农村居民人均农业收入和人均非农收入的影响均是正向显著的,并且有助于区域内农村居民非农收入比重提高,这一效果随试点时间推进不断强化。此外,本文进一步检验了政策性农业保险推广对于城乡关系的间接效应,发现政策性农业保险试点对城镇居民收入的影响不大,对城乡收入差距缩小具有一定作用。     

Default- and call-adjusted duration for corporate bonds

Call and default can potentially alter the timing and amounts of promised cashflows for callable, corporate bonds. While prior research has indicated the theoretical importance of adjusting Macaulay duration for the impacts of default and call, the question of their relative impact remains a matter of debate [The High Yield Debt Market, Dow Jones Irwin, New York, 1990, p. 18; J. Finan. 53 (1998) 2225]. We develop a theoretical analysis incorporating both default and call effects on duration and test its implications employing a previously unexplored data base of Canadian, investment grade, corporate bond indices containing an unusual provision making it possible to identify callable and noncallable indices.     

The Year in Review: Economics at the Antitrust Division, 2005–2006

This paper covers the activities of the Economic Analysis Group (EAG) of the Antitrust Division, U.S. Department of Justice, during 2005–2006. It describes the economic analysis undertaken by EAG in several important investigations, appellate matters, and other activities as an advocate for competition.The views contained herein are solely those of the authors and do not necessarily represent those of the U.S. Department of Justice.     

On Quality and Variety Bias in Aggregate Prices

How do product variety and quality affect the aggregate price bias? We develop a general equilibrium model that accounts for the joint interaction of product quality and variety. Our findings show that the aggregate price bias is procyclical and the contribution of product variety is persistent whereas the contribution of product quality becomes countercyclical in the medium to long run. We show that accounting for product quality and variety has critical implications on the measure of cyclical fluctuations. Measurements of cyclical fluctuations derived using the consumption deflator, which abstracts from changes in product quality and variety, underestimate the variables' true volatility.