Asymptotic subadditivity/superadditivity of Value-at-Risk under tail dependence

This paper presents a new method for discussing the asymptotic subadditivity/superadditivity of Value-at-Risk (VaR) for multiple risks. We consider the asymptotic subadditivity and superadditivity properties of VaR for multiple risks whose copula admits a stable tail dependence function (STDF). For the purpose, a marginal region is defined by the marginal distributions of the multiple risks, and a stochastic order named tail concave order is presented for comparing individual tail risks. We prove that asymptotic subadditivity of VaR holds when individual risks are smaller than regularly varying (RV) random variables with index −1 under the tail concave order. We also provide sufficient conditions for VaR being asymptotically superadditive. For two multiple risks sharing the same copula function and satisfying the tail concave order, a comparison result on the asymptotic subadditivity/superadditivity of VaR is given. Asymptotic diversification ratios for RV and log regularly varying (LRV) margins with specific copula structures are obtained. Empirical analysis on financial data is provided for highlighting our results.     

Stock liquidity and managerial short-termism

We examine whether stock liquidity exacerbates or mitigates managerial short-termism. Utilizing earnings management as a proxy for managerial short-termism, we establish three major findings. First, firms with liquid stocks engage in less accrual-based and real earnings management. Second, the effect of stock liquidity on earnings management is amplified for firms with high levels of managerial pay-for-performance sensitivity. Third, the positive association between the intensity of earnings management and firm cost of capital is evident only for firms with low stock liquidity. Our findings are consistent with the threat of blockholder exit as the main governance channel through which stock liquidity discourages opportunistic earnings management and mitigates managerial short-termism.     

优化外商直接投资结构的研究——基于行业FDI数据的VAR模型

根据1990—2010年全国国内生产总值（GDP）、FDI在制造业的投资额（FM）、FDI在服务业的投资额（FS）、FDI在房地产业的投资额（FRE）及在教育领域的投资额（FE）的统计数据进行基于VAR模型的实证分析,认为长期看,外商在制造业的投资额（FM）和在服务业的投资额（FS）的增加导致全国GDP的增加,外商在房地产业的投资额（FRE）以及在教育领域的投资额（FE）与GDP反向变动;短期看,对全国经济发展的短期影响程度由高到低,依次是FDI在服务业的投资额（FS）、在制造业的投资额（FM）和在教育领域的投资额（FE）以及在房地产业的投资额（FRE）。建议以国务院颁布的《外商投资产业指导目录》为导向,积极利用外资及优化外商投资结构,在发挥外资对我国经济的积极推动作用的同时尽量减少外资的负面影响。     

黑龙江省政策性农业保险影响因素实证分析

通过运用C-D函数对影响黑龙江省农业保险发展的一般因素以及模型外影响黑龙江省农业保险的发展因素进行回归分析,可以看出,影响黑龙江省农业保险发展的因素是农业增加值和政府财政补贴。为促进黑龙江省政策性农业保险的健康发展,应采取加快推进农业现代化进程、优化政府的政策性支持体系、多种渠道促进农民增收、加大保险宣传力度等对策。     

正确定位中职文化课地位与功能推进其改革

文章分析了职业教育的不同阶段,教育界对于文化课地位与功能的不同认识。指出应正确定位中职文化课的地位与功能,从而推进中职文化课在教育观念、课程内容、课程实施、课程评价等方面的改革。     

Accommodating spatial correlation across choice alternatives in discrete choice models: an application to modeling residential location choice behavior

This paper presents a modeling methodology capable of accounting for spatial correlation across choice alternatives in discrete choice modeling applications. Many location choice (e.g., residential location, workplace location, destination location) modeling contexts involve choice sets where alternatives are spatially correlated with one another due to unobserved factors. In the presence of such spatial correlation, traditional discrete choice modeling methods that are often based on the assumption of independence among choice alternatives are not appropriate. In this paper, a Generalized Spatially Correlated Logit (GSCL) model that allows one to represent the degree of spatial correlation as a function of a multi-dimensional vector of attributes characterizing each pair of location choice alternatives is formulated and presented. The formulation of the GSCL model allows one to accommodate alternative correlation mechanisms rather than pre-imposing restrictive correlation assumptions on the location choice alternatives. The model is applied to the analysis of residential location choice behavior using a sample of households drawn from the 2000 San Francisco Bay Area Travel Survey (BATS) data set. Model estimation results obtained from the GSCL are compared against those obtained using the standard multinomial logit (MNL) model and the spatially correlated logit (SCL) model where only correlations across neighboring (or adjacent) alternatives are accommodated. Model findings suggest that there is significant spatial correlation across alternatives that do not share a common boundary, and that the GSCL offers the ability to more accurately capture spatial location choice behavior.     

市域轨道交通线路合理经济长度研究

在理论分析的基础上,从经济角度出发研究市域轨道交通合理的经济长度。以乘客旅行次数需求密度函数为基础,建立市域轨道交通线路长度效益函数和成本函数,其中效益函数包括旅客时间节省效益函数和票价收入效益函数;成本函数包括建设成本函数和运营成本函数,效益函数和成本函数相加即为市域轨道交通社会效益最大化的目标函数。通过建立社会效益函数的非线性函数,建立模型求解,得出合理的市域轨道交通经济长度。     

我国铁路基础设施噪声的边际成本定价方法研究

通过概述国内外学者关于运输外部性内部化政策、运输外部性评估、运输外部成本计算方法等方面的研究成果,阐述了美国及欧盟寻求实现运输外部成本内部化的政策和方法。针对我国铁路基础设施噪声污染问题,在分析铁路噪声的产生、传播及估算的基础上,研究提出利用边际成本定价方法计算铁路噪声边际成本。噪声定价方法还有支付意愿法、冲击路径法等,这些定价方法及其实证量化还有待进一步深入研究。     

工程项目成本管理的问题以及成本控制研究

我国当前的工程项目成本管理体系很不完善。文章简要分析了成本管理中的主要问题,提出通过加强材料成本管理和目标成本管理,提高工程项目成本控制的有效性。     

浅议施工企业项目成本控制

矿山施工市场竞争激烈,施工企业的利润空间越来越小,这就要求施工企业不断提高项目管理水平.施工项目成本控制就是重要的途径.本文指出了煤矿施工项目管理组织的建立,成本目标确定的过程,明确施工项目成本考核奖惩的方法和步骤.