收益最大化中心选址问题的数学模型

物流中心的选址问题在物流中心的规划设计中占有重要的战略地位,合理的物流中心选址方案可以有效地节约费用,提高企业的竞争力。文章针对第三方物流企业选址的要求,以物流中心收益最大化为目标,并同时考虑物流中心固定运营成本和可变运营成本以及退货所产生的损失费用等因素,建立了一个新的物流中心选址模型。并针对该模型,提出了一种改进的微粒群算法。     

Business incomes in rural Nicaragua: the role of household resources,location, experience and trust

This paper analyses the determinants of business income for rural households in Nicaragua. A sample of 1030 households was studied in order to assess the importance of material and behavioural factors that influence income from business activity. The households are involved in manufacturing, trade, services or have a mixture of businesses. They generally have a low income and asset value. Households supplement their income from wages and agricultural activities. To estimate non-farm business income per employed person we analyse the impact of resources, location, entrepreneurial experience and trust. Our results show that household resources and entrepreneurial experience are significant determinants for business income in all sectors. Trust is also important, particularly generalized trust. The contribution of other forms of trust, such as institutional trust, depends on the sector in which households participate.     

土地一级开发中储备土地出让价格影响研究——以武汉市后湖地区为例

研究目的为了解武汉市后湖地区土地一级开发中基础设施投入对土地产出效益的影响,为政府的投资决策提供参考。研究方法为层次分析法和经济学研究方法。研究结果为（1）土地储备中道路设施投入对土地价格的影响最显著,权重系数为0．211;（2）随着道路设施投入的增加,土地产出效益呈先递增后递减的趋势,其影响路径符合边际报酬递减规律。研究结论为在土地一级开发中应注重道路等基础设施的投入,同时要遵循边际报酬递减规律,减少投入的盲目性,避免粗放的经营发展方式,进而控制土地储备成本,提高土地的投入产出效率。     

消费对经济增长的拉动作用研究——基于城乡消费结构的比较

消费是一个国家经济增长的源动力,是公民福利增加的源泉,如何发挥消费对经济的拉动作用已成为学术界研究的热点问题。基于城乡消费结构比较的视角,就消费对经济的拉动作用以及我国城乡居民消费结构的差异进行了研究,结果显示：消费对经济增长具有积极的拉动作用;居民收入水平较低、收入水平差距较大是我国城乡居民消费对经济增长拉动作用较小的重要原因;我国城乡居民的消费结构存在差别,主要原因在于城乡收入水平的差别,持续强劲的居民消费需要以居民的收入持续增加为基础。为此,应从提高居民收入水平、减小城乡居民收入差距、建立完善的医疗保障体系、合理的消费引导等方面来改善城乡居民的消费结构,以真正发挥消费对经济增长的促进作用。     

一种离散型收入分布基尼系数精确计算方法

基尼系数问世八十多年的时间里,在度量经济不平等的基尼系数指标时,最常见的是离散型收入分布,本文设计了一种离散型收入分布基尼系数计算方法,用它可以精确地求解基尼系数。     

以提高农民收入水平为抓手建设和谐美丽新云南

农民收入问题事关国民经济协调发展和社会和谐稳定。本文在分析云南农民收入水平低、城乡收入差距大、地区不平衡突出、贫困人口多,从而制约着云南科学发展、和谐发展与跨越发展基础上,提出建设和谐美丽新云南应以提高农民收入水平为抓手,发挥云南比较优势、统筹城乡协调发展、依靠科技进步和增强农民增收本领等举措促进农民增收和保持农民收入持续较快增长。     

Should public policy respond to positional externalities?

A nice suit is one that compares favorably with those worn by others in the same local environment. More generally, a positional good is one whose utility depends strongly on how it compares with others in the same category.¹A positional externality occurs when new purchases alter the relevant context within which an existing positional good is evaluated.² For example, if some job candidates begin wearing expensive custom-tailored suits, a side effect of their action is that other candidates become less likely to make favorable impressions on interviewers. From any individual job seeker's point of view, the best response might be to match the higher expenditures of others, lest her chances of landing the job fall. But this outcome may be inefficient, since when all spend more, each candidate's probability of success remains unchanged. All may agree that some form of collective restraint on expenditure would be useful.In such cases, however, it is often impractical to negotiate private solutions. Do positional externalities then become legitimate objects of public policy concern? In attempting to answer this question, I employ the classical libertarian criterion put forth by John Stuart Mill³, who wrote the state may not legitimately constrain any citizen's freedom of action except to prevent harm to others. I argue that many positional externalities appear to meet Mill's test, causing not just negative feelings but also large and tangible economic costs to others who are ill-equipped to avoid them. I also discuss an unintrusive policy remedy for positional externalities, one modeled after the use of effluent charges to curb environmental pollution.The paper is organized as follows. Section 1 notes the deep similarity between the conditions that give rise to positional arms races and those that give rise to conventional military arms races. Section 2 follows with a review of evidence concerning the strength of concerns about relative position. Section 3 describes some of the tangible economic costs that people experience as a result of positional externalities arising from such concerns. Section 4 takes up the question of whether collective action directed against positional externalities is consistent with respect for individual rights. Section 5 describes how a progressive consumption tax could neutralize many of the most costly effects of positional externalities.     

Coping with Technological Change: The Role of Ability in Making Inequality so Persistent

This study provides an explanation to the evolution of wage inequality over the last 30 years and supports this explanation with evidence. A faster rate of technological progress introduces new unknown elements at the workplace. The need to cope with the unknown accentuates the role of ability and thus increases wage inequality within and between education groups. Inasmuch as education is an irreversible investment project the rise in within group inequality BOOSTS UP the rise of between group inequality. Guided by this theory we turn to the PSID for evidence. Using parents' education to approximate child's ability we show the following set of results: (a) Controlling for education of the child, parents' education contributed much more in the 1980s to his wage growth than in the 1970s. (b) The correlation between the parents' and the child's education increases from the 1970s to the 1980s. (c) The return to college education for an individual with no ability rents did not change—it remains steady at the 23 percent. (d) Facts (a)–(c) CANNOT be attributed to the impact of parent's income. It is parents' education and not parents' income that is more relevant for son's economic outcomes in the 1980s.     

会计稳健性、经济租金与企业剩余收益

通过实证研究会计稳健性与企业剩余收益的关系,以及会计稳健性与经济租金对企业剩余收益的交互影响,发现会计稳健性与企业的剩余收益显著正相关,而会计稳健性和经济租金对企业剩余收益的交互影响较为复杂,其中：稳健性与研发密度、广告密度对剩余收益有显著的正面影响,但稳健性与企业规模、市场份额、流通股比例和资本密度对剩余收益的交互效应不明显。可见,提高会计稳健性,并不一定能为企业带来额外的经济租金收益。     

The determinants of commercial banking profitability in low-, middle-, and high-income countries

Using a broad bank-level dataset and the GMM estimator technique described by Arellano and Bover (1995), this paper analyses how bank-specific characteristics, macroeconomic variables, and industry-specific factors affect the profitability of 10,165 commercial banks across 118 countries over the period from 1998 to 2012. Grouping the countries according to three income levels, we show that the determinants of bank profitability included in our model can explain existing profitability differences among commercial banks in low-, middle-, and high-income countries. The profitability determinants vary quite widely across the different levels of income in terms of significance, sign and size of the effect. The level of income has thus an important impact on the determinants of bank profitability.