函数型变量倾斜分位回归模型及其应用

本文考虑函数型数据的结构特征,针对两类函数型变量分位回归模型（函数型因变量对标量自变量和函数型因变量对函数型自变量）,基于函数型倾斜分位曲线的定义构建新型函数型倾斜分位回归模型。对于第二类模型,本文分别考虑样条基函数对模型系数展开和函数型主成分基函数对函数型自变量展开,得到倾斜分位回归模型的基本形式。参数估计采用成分梯度Boosting算法最小化加权非对称损失函数,提高计算效率。在理论上证明了倾斜分位回归模型的系数估计量均服从渐近正态分布。模拟和实证研究结果显示,倾斜分位回归模型比已有的逐点分位回归模型具有更好的拟合效果。根据积分均方预测误差准则,本文提出的模型有一致较好的预测能力。     

Analysis of the response structure to a set of questions with large number of scale points: a new combined metric and categorical approach

In the field of social sciences, certain tasks, such as the identification of typologies and the characterization of groups of individuals according to a set of questions, tend to pose a challenge for researchers. Further complications arise if the chosen rating scale is from 0 to 10, since the responses can be treated either as metric or categorical variables. This paper shows that neither treatment is able on its own to capture all the inherent properties of this type of data, and goes on to propose a bicriteria clustering approach, which captures both perspectives and enables the simultaneous analysis of mixed data using multiple tables.     

多元智能理论及其对民族教育的启示

1983年加德纳提出的多元智能理论,对传统智力观发出挑战,认为人至少具有八种同等重要的智能,它的有关智能的理论对我国发展民族教育具有重大的启示.     

Explicit formulas for generalized family-wise error rates and unimprovable step-down multiple testing procedures

Many multiple testing procedures (MTPs) are available today, and their number is growing. Also available are many type I error rates: the family-wise error rate (FWER), the false discovery rate, the proportion of false positives, and others. Most MTPs are designed to control a specific type I error rate, and it is hard to compare different procedures. We approach the problem by studying the exact level at which threshold step-down (TSD) procedures (an important class of MTPs exemplified by the classic Holm procedure) control the generalized FWER   defined as the probability of k$k$ or more false rejections. We find that level explicitly for any TSD procedure and any k$k$. No assumptions are made about the dependency structure of the p$p$-values of the individual tests. We derive from our formula a criterion for unimprovability   of a procedure in the class of TSD procedures controlling the generalized FWER at a given level. In turn, this criterion implies that for each k$k$ the number of such unimprovable procedures is finite and is greater than one if k>1$k>1$. Consequently, in this case the most rejective procedure in the above class does not exist.     

A Simulation Study of the Powers of Three Multiple Comparison Statistics

A normal-theory and two distribution-free statistics used for multiple comparisons of homogeneity of location are compared on simulated data generated from six distributions. The normal-theory statistic is found to be fairly robust to departures from the assumption of normally distributed data of the types considered. The Steel-Dwass statistic is generally more powerful than a Kruskal-Wallis range statistic.     

The identifiability of the mixed proportional hazards competing risks model

Summary. We prove identification of dependent competing risks models in which each risk has a mixed proportional hazard specification with regressors, and the risks are dependent by way of the unobserved heterogeneity, or frailty, components. We show that the conditions for identification given by Heckman and Honoré can be relaxed. We extend the results to the case in which multiple spells are observed for each subject.     

Job stressors,coping, and psychological distress among Japanese employees: Interplay between active and non-active coping

In this study the sole and the combined effects of active and non-active forms of coping on psychological distress across various kinds of job stressors were examined. Data on job stressors, coping and psychological distress were obtained from 4487 male employees of a research institute in the automobile industry in Japan (mean age=36.27 years, SD = 7.43). A hierarchical moderated multiple regression analysis was conducted to estimate and test the significance of the main effects and their interactions. The results show that although active coping was effective in decreasing psychological distress regardless of the type of job stressor, the effectiveness was weaker in situations that require effortful coping, such as role ambiguity and insufficient authority. Furthermore, the effectiveness of active coping was influenced by the other strategies, especially in effortful coping situations. While distancing or seeking social support improved the effectiveness, restraint coping reduced it. These results suggest that the type of non-active coping that individuals combine with active coping can be critical in determining health outcomes in more complex and effortful coping situations. Consideration of the coping combinations, not merely the situational context, is important in explaining how the work environment influences employees' psychological distress.     

Robustness of the Multiple Correlation Coefficient When Sampling From a Mixture of Two Multivariate Normal Populations

The density of the multiple correlation coefficient is derived by direct integration when the sample covariance matrix has a linear non-central distribution. Using the density, we deduce the null and non-null distribution of the multiple correlation coefficient when sampling from a mixture of two multivariate normal populations with the same covariance matrix. We also compute actual significance levels of the test of the hypothesis H_o : ρ_1·2…p = 0 versus H_a:ρ_1·2…p > 0, given the mixture model.     

Analysis of a long-term study of neurotic disorder, with insights into the process of non-response

Summary.  The paper studies the non-response process in a long-term study of neurotic dis-order by comparing the analysis based on the responses that were collected by the established practice of interviewing the subjects, at dates arranged in advance (appointments), with the analysis of the nearly complete set of responses that were collected by an extensive effort that involved attempts to interview without seeking a prior agreement. The method of multiple imputation is applied, and its properties are explored in a setting that is not perfectly suited for its application: a relatively small sample size, ordinal score outcomes and the likelihood that the outcomes are missing not at random.     

Bayesian projection of the acquired immune deficiency syndrome epidemic

Short-term projections of the acquired immune deficiency syndrome (AIDS) epidemic in England and Wales have been regularly updated since the publication of the Cox report in 1988. The key approach for those updates has been the back-calculation method, which has been informally adapted to acknowledge various sources of uncertainty as well as to incorporate increasingly available information on the spread of the human immunodeficiency virus (HIV) in the population. We propose a Bayesian formulation of the back-calculation method which allows a formal treatment of uncertainty and the inclusion of extra information, within a single coherent composite model. Estimation of the variably dimensioned model is carried out by using reversible-jump Markov chain Monte Carlo methods. Application of the model to data for homosexual and bisexual males in England and Wales is presented, and the role of the various sources of information and model assumptions is appraised. Our results show a massive peak in HIV infections around 1983 and suggest that the incidence of AIDS has now reached a plateau, although there is still substantial uncertainty about the future.