资本回报率、人力资本投资与收入不平等——基于Galor-Zeira模型的扩展

资本回报率下降对人力资本投资、收入不平等程度有较大影响。本文将可变资本回报率加入Galor-Zeira模型,理论推导发现:收入不平等陷阱并非不可逾越的障碍。当技能劳动力工资高于受教育固定成本时,随着资本回报率下降,接受教育的遗赠临界水平将降低,更多家庭将发现投资人力资本是有利的,稳态的技能劳动力比例将提高。在当前资本回报率下降的大背景下,提高技能劳动力工资、降低受教育成本、对教育贷款实施财政减免优惠、为农村中等教育支出减负和提升农村教育质量、倡导节俭和重视遗赠的文化氛围在长期都有助于提高技能劳动力比重以及缓和收入不平等。     

辽西北地区农业干旱危险性评价与区划

[目的]开展农业干旱危险性评价与区划研究,为辽宁省西北地区农业防旱抗灾工作提供科学依据。[方法]文章根据联合国国际减灾战略署(ISDR)对农业干旱危险性的定义,分析了构成研究区作物干旱危险性的致灾因子和孕灾环境因子,采用层次分析法确定了各因子的权重,构建了研究区农业干旱危险性评价指标和模型。以2009年为例,通过利用降雨、土壤、农业生产类型及地形等数据计算了辽西北地区农业干旱危险性评价指数,利用自然间断点法分级干旱危险性评价指数,并借助GIS技术,绘制研究区农业干旱危险性等级区划图。[结果] 2009年作物生长期间研究区农业干旱危险性由高到低排列为:朝阳市葫芦岛市锦州市阜新市铁岭市沈阳市。[结论]辽西北地区农业干旱危险性等级区的划分,能够帮助政府管理部门为面临干旱威胁不同的区域建立适当的防灾方法和有效的应急预案。     

Is Volatility the Best Predictor of Market Crashes?

The objective of this paper is to determine the best predictor of equity market crashes by focusing particularly on volatility and market liquidity. In finance, volatility has traditionally been regarded as the best measure of market risk. However, this paper shows that the forecast value of market liquidity, in particular our modified calculated market depth, predicts equity market crashes much more accurately than does the forecast values of EGARCH or Implied Volatility.     

上市公司CEO的监管机制：一个三方博弈视觉的思考

所有权与经营权的分离是现代企业的基本特征,内部人控制问题已成为制约上市公司健康稳定发展的瓶颈因素。本文通过建立一个CEO、董事会和外部监管机构三方之间的博弈模型,强调了监管的重要性;并从完善董事会职能和加强外部监管力度两个方面对上市公司CEO的道德风险之监管提出合理性建议。     

A Dynamic Analysis of Fixed- and Adjustable-Rate Mortgage Terminations

This paper provides a side-by-side comparison of loan-level statistical models for fixed- and adjustable-rate mortgages. Multinomial logit models for quarterly conditional probabilities of default and prepayment are estimated. We find that the estimated impacts of embedded option values for prepayment and default are generally quite similar across both FRM and ARM loans, providing additional empirical support for the basic predictions of the options theory. We also find that differences in estimates of conditional probabilities of prepayment and default associated with mortgage age, origination period, original LTV, and relative loan size, indicate the continued significance of these other economic and demographic factors for empirical models of mortgage terminations.     

精馏过程的节能和优化设计的探讨

精馏过程的节能,对于减少能源消耗,降低生产成本和保护环境具有十分重要的意义.在精馏过程中可以采用最适宜回流比操作和最佳进料状态,使用中间冷凝器和中间再沸器,高效精馏、热泵精馏.合理安排多组分物料分离流程,直接利用过程热量及开发应用高效换热器等措施.本文从最佳回流比R的选择、进料温度及进料状态的确定等方面,详细的分析了在精馏塔的设计过程中,如何实现设计的优化问题,以实现节能降耗.     

对小地区失业统计差额比的推定

本文对韩国国内行政区域如市郡区等小地区的失业统计共同差额比进行推定的方法有联合推定量,Woolf推定量和Mantel-Haenszel推定量等。对这个推定量的可信度是通过偏差和平均平方误差的概念来进行比较的。从对京畿地区经济活动人口调查情况看,这个地区内的24个市郡单位行政自治地区的男、女失业率差额比的偏差及平均平方误差是通过本次研究提出的推定程序来推定的。这些推定数的稳定性和效率性可以通过相对偏差和相对平均误差平方根来评价。Woolf推定量或Mantel-Haenszel推定量比联合推定量更为稳定,从其效率性来看三者很相似。     

中国税收流失规模估测

无论地下经济还是公开经济都存在税收流失问题.本文采用一定的方法分别对我国1982-2002年间地下经济和公开经济的税收流失规模进行了估测.从税收流失的规模角度看,我国税收的汲取能力比较弱,蕴涵着很大的税收风险.减少税收流失应作为税制改革的重要目标.     

浙江上市公司总体分析

浙江上市公司从数量上看，占了相当优势，排在全国的第4位，而且至今还未曾有退市的公司；从质量上看，也有较突出的特征，该板块的平均净资产值较高，按上市公司数量排的全国前10位中，排在第1位，达3．23元；从市盈率来看也说明了浙江板块的业绩较好，平均市盈率已达17．66倍。但也存在不足的一面，从对社会贡献的总量来看，还不是很突出，缺乏规模效益。     

FACTORS THAT AFFECT THE LONG‐TERM SURVIVAL OF MICRO,SMALL AND MEDIUM ENTERPRISES IN ETHIOPIA

There is an increasing recognition of the potential importance of micro, small and medium enterprises (MSMEs) for employment, income and poverty reduction in Ethiopia. Although the MSME sector contributes significantly to the national economy, the high failure rate among well established small businesses and enterprises is a matter of major concern. A random sample of 500 small businesses and enterprises selected from five major cities in Ethiopia were followed up for 6 years in order to assess the impact of influential factors that affect the long‐term survival and viability of small enterprises. Hazard ratios estimated from the Cox Proportional Hazards Model were used to quantify the impact of key predictors of survival. Businesses that ceased operation were characterised by inadequate finance (61%), low level of education (55%), poor managerial skills (54%), shortage of technical skills (49%), and inability to convert part of their profit to investment (46%). The study shows that participation in social capital and networking (iqqub schemes) was critically helpful for long‐term survival. Businesses that did not participate in iqqub schemes regularly were found to be 3.25 times more likely to fail in comparison with businesses that did. Results of the study have implications that could be used for developing policy initiatives that are aimed at fostering long‐term growth in small businesses and enterprises.