Noninformative priors for the normal variance ratio

In this paper, we consider noninformative priors for the ratio of variances in two normal populations. We develop first and second order matching priors. We find that the second order matching prior matches alternative coverage probabilities up to the second order and is also a HPD matching prior. It turns out that among the reference priors, only one-at-a-time reference prior satisfies a second order matching criterion. Our simulation study indicates that the one-at-a-time reference prior performs better than other reference priors in terms of matching the target coverage probabilities in a frequentist sense. This work is supported by Korea Research Foundation Grant (KRF-2004-002-C00041).     

On the stability of the risk hull method for projection estimators

We consider in this paper the regularization by projection of a linear inverse problem Y=Af+εξ$Y=\mathit{Af}+\epsilon \xi$ where ξ$\xi$ denotes a Gaussian white noise, A   a compact operator and ε>0$\epsilon >0$ a noise level. Compared to the standard unbiased risk estimation (URE) method, the risk hull minimization (RHM) procedure presents a very interesting numerical behavior. However, the regularization in the singular value decomposition setting requires the knowledge of the eigenvalues of A$A$. Here, we deal with noisy eigenvalues: only observations on this sequence are available. We study the efficiency of the RHM method in this situation. More generally, we shed light on some properties usually related to the regularization with a noisy operator.     

The declining influence of family background on educational attainment in Australia: The role of measured and unmeasured influences

The paper examines changes in the influence of family background, including socioeconomic and social background variables on educational attainment in Australia for cohorts born between 1890 and 1982. We test hypotheses from modernization theory on sibling data using random effects models and find: (i) substantial declines in the influence of family background on educational attainment (indicated by the sibling intraclass correlations); (ii) declines in the effects of both economic and cultural socioeconomic background variables; (iii) changes in the effects of some social background variables (e.g., family size); (iv) and declines in the extent that socioeconomic and social background factors account for variation in educational attainment. Unmeasured family background factors are more important, and proportionally increasingly so, for educational attainment than the measured socioeconomic and social background factors analyzed. Fixed effects models showed steeper declines in the effects of socioeconomic background variables than in standard analyses suggesting that unmeasured family factors associated with socioeconomic background obscure the full extent of the decline.     

关于农民的财政不公平与公平财政的改革

长期以来,农民负担十分沉重,其主要原因是财政的不公平待遇。虽然经济体制改革前后农民交纳的形式不同,但其实质均体现为农民的财政不公平。解决此问题的关键是通过实施针对农民的公平财政改革。在现阶段,统一城乡税制的改革不能急于求成,可先行建立“社会补偿”制度与“逆向税制”政策。     

Societal Inequality and individual subjective well-being: Results from 68 societies and over 200,000 individuals, 1981–2008

Income inequality has been contentious for millennia, a source of political conflict for centuries, and is now widely feared as a pernicious “side effect” of economic progress. But equality is only a means to an end and so must be evaluated by its consequences. The fundamental question is: What effect does a country's level of income inequality have on its citizens' quality of life, their subjective well-being? We show that in developing nations inequality is certainly not harmful but probably beneficial, increasing well-being by about 8 points out of 100. This may well be Kuznets's inverted “U”: In the earliest stages of development some are able to move out of the (poorly paying) subsistence economy into the (better paying) modern economy; their higher pay increases their well-being while simultaneously increasing inequality. In advanced nations, income inequality on average neither helps nor harms. Estimates are from random-intercept fixed-effects multi-level models, confirmed by over four dozen sensitivity tests. Data are from the pooled World Values/European Values Surveys, Waves 1 to 5 with 169 representative national samples in 68 nations, 1981 to 2009, and over 200,000 respondents, replicated and extended in the European Quality of Life Surveys.     

收入差距、社会稳定与经济增长

收入差距问题不仅涉及经济学上的效率与公平,而且关系着社会稳定和经济的可持续增长。如果收入差距过度扩大特别是贫富两极分化,必然会危及社会的组织和秩序,甚至诱发社会动乱,从而使经济增长失去稳定的社会环境。完善社会主义市场经济体制,统筹城乡和区域的经济与社会发展,应把调节收入差距作为一个中心环节,培育一个可持续发展的、公正和谐与公众广泛参与的社会,实现社会主义以人为本的全面发展。     

光学优化设计中的定域法研究

介绍了一种定域型优化设计算法──不等式法,借助于Ｃ＋＋开发程序将该方法运用于光学优化设计中,设计了几种典型的光学系统。设计过程和设计结果表现出了这种算法的快速、稳定收敛性,且符合传统的设计思想。     

中国城镇居民功能不平等计量分析——基于阿马蒂亚·森的能力方法

以阿马蒂亚.森的能力方法为基础,利用问卷调查获得的数据对我国城镇居民功能不平等进行测算的计量结果表明,我国城镇居民功能不平等程度远低于收入分配不平等程度。从城镇居民功能不平等计量结果来看,目前我国社会相对稳定,但局面不容乐观,社会不稳定因素仍然存在。当前我们要关注收入分配不平等,也要关注人们在住房、休闲、人际关系、健康、工作满意度等功能分配方面的不平等。     

Field of study variation throughout the college pipeline and its effect on the earnings gap: Differences between ethnic and immigrant groups in Israel

This study demonstrates the analytical leverage gained from considering the entire college pipeline—including the application, admission and graduation stages—in examining the economic position of various groups upon labor market entry. The findings, based on data from three elite universities in Israel, reveal that the process that shapes economic inequality between different ethnic and immigrant groups is not necessarily cumulative. Field of study stratification does not expand systematically from stage to stage and the position of groups on the field of study hierarchy at each stage is not entirely explained by academic preparation. Differential selection and attrition processes, as well as ambition and aspirations, also shape the position of ethnic groups in the earnings hierarchy and generate a non-cumulative pattern. These findings suggest that a cross-sectional assessment of field of study inequality at the graduation stage can generate misleading conclusions about group-based economic inequality among workers with a bachelor’s degree.     

矢量法在数学求解问题中的应用

矢量代数是数学中最活跃的分支之一,矢量深刻的描述了现实世界的空间形式,是沟通数与形内在联系的有力工具,因而利用矢量的运算解决数学问题具有很强的优越性。