高校毕业生就业率统计方法探析

随着我国由计划经济体制向市场经济体制转变，大学生就业也由统包统配向自主择业转变，高校就业率统计工作如何适应形势的发展，从而能够科学、准确地反映出高校实际的就业状况和办学水平，使之能够促进高校教育健康发展是一个值得研究的课题，本文主要总结了我国近年来就业率统计方式的形成、演变过程及现行就业率统计中存在的问题，为就业率统计方法的改革研究奠定基础。     

COVARIANCE MODELS FOR LATTICE DATA

Given observations on an m × n lattice, approximate maximum likelihood estimates are derived for a family of models including direct covariance, spatial moving average, conditional autoregressive and simultaneous autoregressive models. The approach involves expressing the (approximate) covariance matrix of the observed variables in terms of a linear combination of neighbour relationship matrices, raised to a power. The structure is such that the eigenvectors of the covariance matrix are independent of the parameters of interest. This result leads to a simple Fisher scoring type algorithm for estimating the parameters. The ideas are illustrated by fitting models to some remotely sensed data.     

江西流动人口规模的统计预测与分析

据有关数据显示,江西省目前有300多万的流动人口规模,随着经济的发展,江西省的流动人口将趋于增长。文章利用统计预测方法,从三种不同的角度预测了江西省从2005~2050年的流动人口规模,并对如何加强其管理进行了探讨。     

A survey on multivariate chi-square distributions and their applications in testing multiple hypotheses

We are concerned with three different types of multivariate chi-square distributions. Their members play important roles as limiting distributions of vectors of test statistics in several applications of multiple hypotheses testing. We explain these applications and consider the computation of multiplicity-adjusted p-values under the respective global hypothesis. By means of numerical examples, we demonstrate how much gain in level exhaustion or, equivalently, power can be achieved with corresponding multivariate multiple tests compared with approaches which are only based on univariate marginal distributions and do not take the dependence structure among the test statistics into account. As a further contribution of independent value, we provide an overview of essentially all analytic formulas for computing multivariate chi-square probabilities of the considered types which are available up to present. These formulas were scattered in the previous literature and are presented here in a unified manner.     

Using repeated-prevalence data in multi-state modeling of renal replacement therapy

Multi-state models help predict future numbers of patients requiring specific treatments but these models require exhaustive incidence data. Deriving reliable predictions from repeated-prevalence data would be helpful. A new method to model the number of patients that switch between therapeutic modalities using repeated-prevalence data is presented and illustrated. The parameters and goodness of fit obtained with the new method and repeated-prevalence data were compared to those obtained with the classical method and incidence data. The multi-state model parameters’ confidence intervals obtained with annually collected repeated-prevalence data were wider than those obtained with incidence data and six out of nine pairs of confidence intervals did not overlap. However, most parameters were of the same order of magnitude and the predicted patient distributions among various renal replacement therapies were similar regardless of the type of data used. In the absence of incidence data, a multi-state model can still be successfully built with annually collected repeated-prevalence data to predict the numbers of patients requiring specific treatments. This modeling technique can be extended to other chronic diseases.     

A Comparison of the Performance of Phase II Simple Linear Profile Control Charts when Parameters are Estimated

The standard deviation of the average run length (SDARL) is an important performance metric in studying the performance of control charts with estimated in-control parameters. Only a few studies in the literature, however, have considered this measure when evaluating control chart performance. The current study aims at comparing the in-control performance of three phase II simple linear profile monitoring approaches; namely, those of Kang and Albin (2000), Kim et al. (2003), and Mahmoud et al. (2010). The comparison is performed under the assumption of estimated parameters using the SDARL metric. In general, the simulation results of the current study show that the method of Kim et al. (2003) has better overall statistical performance than the competing methods in terms of SDARL values. Some of the recommended approaches based solely on the usual average run length properties can have poor SDARL performance.     

我国人口预期寿命的结构及影响因素研究—基于省级面板数据的分析

基于省级面板数据,本文对预期寿命结构及其影响因素问题进行研究。首先,文章分析了我国整体预期寿命及两性预期寿命的地理分布特性,随时间的变化特点,以及与经济发展水平的关系。然后,建立预期寿命的固定效应模型,分析不同影响因素与预期寿命的关系。研究发现经济发展水平、教育和卫生资源对男性和女性预期寿命会产生不同的影响,其中经济发展水平会显著影响女性预期寿命,而教育对男性预期寿命的影响更显著。由此,经济发展水平的提高会导致两性预期寿命差距的增加,而教育水平的提高和卫生资源投入的增加则可能会降低两性预期寿命的差距。     

Individual and Household Values of Mortality Reductions with Intrahousehold Bargaining

I derive alternative measures of maximum willingness to pay (WTP) and value of statistical life (VSL) for selfish members of two-person households who bargain efficiently over consumption of individual and household goods. There is then no systematic bias in letting one member conduct the valuation on behalf of the household. Public-good VSL may exceed private-good VSL when each member attaches (selfish) preferences to survival of the spouse, and to any income from a surviving spouse in period 2. When period 2 is a retirement period and household members’ incomes are fixed, interview surveys tend to overvalue VSL due to ignored negative effects of own survival on private of public pension budgets.JEL Classification: I12, G22, J17     

Is Transport Safety More Valuable in the Air?

Using a contingent valuation survey, people's willingness to pay for a given risk reduction is found to be much larger, consistently more than two times as large, when traveling by air compared to by taxi. Follow-up questions revealed that an important reason for this discrepancy is that many experience a higher mental suffering from flying, and that they are willing to pay to reduce this suffering. It was also consistently found that people are willing to pay more for a certain risk reduction if the original price was higher. Policy implications are discussed.     

Effects of Disease Type and Latency on the Value of Mortality Risk

We evaluate the effects of disease type and latency on willingness to pay (WTP) to reduce environmental risks of chronic, degenerative disease. Using contingent-valuation data collected from approximately 1,200 respondents in Taiwan, we find that WTP declines with latency between exposure to environmental contaminants and manifestation of any resulting disease, at a 1.5 percent annual rate for a 20 year latency period. WTP to reduce the risk of cancer is estimated to be about one-third larger than WTP to reduce risk of a similar chronic, degenerative disease. The value of risk reduction also depends on the affected organ, environmental pathway, or payment mechanism: estimated WTP to reduce the risk of lung disease due to industrial air pollution is twice as large as WTP to reduce the risk of liver disease due to contaminated drinking water.