单位根的秩检验及其应用研究

 本文系统研究了单位根检验的三种非参数秩检验统计量：RDF检验、得分秩( )检验与逆得分秩( )检验,推导了逆得分秩的分布。然后运用Monte Carlo模拟给出了各种秩检验的临界值,将秩检验与传统检验的优劣进行了比较,并将这些方法应用于我国货币需求函数各变量月度序列的实证检验。Monte Carlo模拟和实证应用的结果表明,秩检验与传统单位根检验方法相结合可以发现序列中的非线性特征,这将有助于对时间序列特征的深入分析。     

Psychological ‘self–other overlap’ and support for slavery reparations

Neurobiological and social psychological studies suggest the existence of non-conscious ‘self–other overlap’ that can lead individuals to identify with other individuals or groups. This paper investigates whether this effect may help to explain support by some Whites for an otherwise unpopular policy on behalf of African Americans-slavery reparations. A representative telephone survey (n = 1200) serves as baseline of comparison for an online reaction time study with a non-representative sample (n = 1341) that measures ‘self–other overlap’ (interchangeably referred to as “implicit closeness” to Blacks). Partial proportional odds ordered logit analyses reveal implicit closeness to Blacks as the single most powerful predictor of support for reparations among White respondents. The magnitude of the absolute effect of implicit closeness exceeds that of traditional predictors such as racial resentment, ideology, and party identification. Methodological and political implications are discussed.     

Scholastic ability vs family background in educational success: evidence from Danish sample survey data

This research examines the role of scholastic ability and family background variables in the determination of educational attainment in Denmark. A categorical representation of the highest level of education attained by the individual is the dependent variable. It is analyzed by procedures that take account of the presence of unobservable factors. Parent’s education and occupation, along with an indicator of scholastic ability which is represented by a set of aptitude tests, explain a small but significant portion of the variation in their children’s educational success. Women are shown to respond differently to their environments than men, and including these test scores does not remove the need to deal with unmeasured attributes. On the basis of the available data, family background variables as a group contribute more to the explained variation in the data than the test scores. Finally, credit constraints do not appear to be a factor in educational attainments.

试论执业医师资格考试的影响因素

我国《执业医师法》已经实施以来,由于我国的政治、经济体制不断变革,国际医学教育形势发生了深刻变化,使《执业医师法》在实施过程中遇到了一些具体问题。在分析执业医师考试影响因素的基础上,与国外执业医师考试的做法进行比较,提出对我国执业医师考试考生报考资格进行修改的建议,有利于加强我国医师队伍的规范化管理,确保医师队伍整体素质的不断优化和提高。     

Ability and rates of return to schooling—making use of the Swedish enlistment battery test

Using the Swedish military enlistment test, this paper estimates the return to schooling for individuals belonging to different parts of the ability distribution. It also attempts to predict whether an endogenous test score causes bias in the “ability-specific” returns to schooling that varies with the test score. A significant finding is that a higher score in the test is associated with a higher return to schooling, but that the positive association is diminishing in the test score. In general, the bias in the ability-specific returns to schooling does not seem to vary with the test score level.

Demographics,the Third Age and partial retirement: Policy proposals to accommodate the changing picture of female retirement in Canada

Much concern has been raised around the potential impact of the retirement of the large baby boom generation. This article specifically addresses the unique issues surrounding the retirement of female baby boomers. Demographic changes, including increased labor force participation, coupled with declining fertility rates, have resulted in a social transformation of the roles women play in society. Despite these changes, women still bear much of the caregiving responsibilities in the household, which can complicate retirement choices. This article examines female retirement in the Canadian context and presents three policy proposals to expand women’s retirement choices, encourage longer-term labor force participation, and thereby extend their working lives into the Third Age.     

Percentage points of LRC for testing equality of covariance matrices under intraclass correlation structure

The exact null distribution of the likelihood ratio test statistic for testing equality of covariance matrices of q compound symmetric Gaussian models (bivariate or trivariate) has been obtained and percentage points for q ? 5 have been computed. The inverse Mellin transform and calculus of residues have been used to derive these results.     

Bayesian variable selection in Poisson change-point regression analysis

In this article, we develop a Bayesian variable selection method that concerns selection of covariates in the Poisson change-point regression model with both discrete and continuous candidate covariates. Ranging from a null model with no selected covariates to a full model including all covariates, the Bayesian variable selection method searches the entire model space, estimates posterior inclusion probabilities of covariates, and obtains model averaged estimates on coefficients to covariates, while simultaneously estimating a time-varying baseline rate due to change-points. For posterior computation, the Metropolis-Hastings within partially collapsed Gibbs sampler is developed to efficiently fit the Poisson change-point regression model with variable selection. We illustrate the proposed method using simulated and real datasets.     

Improved tests for homogeneity of variances

Equality of variances is one of the key assumptions of analysis of variances (ANOVA). There are several testing procedures available to validate this assumption, but it is rare to find a test procedure which controls the type I error rate while providing high statistical power. In this article, we introduce a bootstrap test based on the ratio of mean absolute deviances (RMD). We also propose a two-stage testing procedure where we first quantify the skewness of the distributions and then choose an appropriate test for homogeneity of variances. The performances of these test procedures are studied via a simulation study.