Estimation and inference of combining quantile and least-square regressions with missing data

In this paper, we consider how to incorporate quantile information to improve estimator efficiency for regression model with missing covariates. We combine the quantile information with least-squares normal equations and construct an unbiased estimating equations (EEs). The lack of smoothness of the objective EEs is overcome by replacing them with smooth approximations. The maximum smoothed empirical likelihood (MSEL) estimators are established based on inverse probability weighted (IPW) smoothed EEs and their asymptotic properties are studied under some regular conditions. Moreover, we develop two novel testing procedures for the underlying model. The finite-sample performance of the proposed methodology is examined by simulation studies. A real example is used to illustrate our methods.     

Construction and selection of quick switching double sampling system-acceptance number tightening

This paper presents a new sampling inspection system consisting of simple switching rule. The performance of the system is compared with those of other equivalent plans. Necessary tables are constructed and procedures presented for the selection of the sampling system.     

General Multi-Level Modeling with Sampling Weights

ABSTRACT

In this article we study the approximately unbiased multi-level pseudo maximum likelihood (MPML) estimation method for general multi-level modeling with sampling weights. We conduct a simulation study to determine the effect various factors have on the estimation method. The factors we included in this study are scaling method, size of clusters, invariance of selection, informativeness of selection, intraclass correlation, and variability of standardized weights. The scaling method is an indicator of how the weights are normalized on each level. The invariance of the selection is an indicator of whether or not the same selection mechanism is applied across clusters. The informativeness of the selection is an indicator of how biased the selection is. We summarize our findings and recommend a multi-stage procedure based on the MPML method that can be used in practical applications.     

Handling Uncertainty in the Cost Effectiveness Healthcare Evaluations. A Review of Statistical Approaches

Healthcare economic evaluation is an analytical tool used with increasing frequency to assist decision making in the choice and financing of interventions and technologies in the healthcare system. The objective of this article is to analyze the different methods of handling with sampling uncertainty in healthcare cost effectiveness evaluations when patient level data are available. The aim of this article is to focus on the strengths and the weakness of each method in order to facilitate the tasks of those who must base their choices on studies of this kind.     

被访者驱动抽样：基于多种方法的估计诊断

本文利用RDS样本数据,使用RDS估计器、收敛图、瓶颈图、经纬度信息等,对违反“随机招募假设”的RDS估计进行综合诊断。诊断结果表明,适度违反“随机招募假设”并不会导致严重的RDS偏差,RDS估计仍然是有效的。因此,本文较为系统地介绍了多种诊断方法的实际操作及判断假设违反适度的可能标准,为国内研究者理解RDS方法,推动和发展RDS抽样和统计估计提供了思路。     

Reaching African-American Men on the “Down Low”: Sampling Hidden Populations: Implications for HIV Prevention

ABSTRACT

Studies on the impact of the HIV epidemic among African-American men who have sex with men (MSM) have largely neglected men who self-identify as heterosexual but engage in same-sex behavior. These men, commonly referred to as men on the “down low,” pose formidable challenges to researchers conducting prevention studies. This article addresses the methodological issues that create limitations in sampling this population. It presents a novel approach to locate and access these men, describes the success in using this approach, and suggests implications for future research employing this sampling approach.     

Some new results on univariate and multivariate permutation tests for ordinal categorical variables under restricted alternatives

In several sciences, especially when dealing with performance evaluation, complex testing problems may arise due in particular to the presence of multidimensional categorical data. In such cases the application of nonparametric methods can represent a reasonable approach. In this paper, we consider the problem of testing whether a “treatment” is stochastically larger than a “control” when univariate and multivariate ordinal categorical data are present. We propose a solution based on the nonparametric combination of dependent permutation tests (Pesarin in Multivariate permutation test with application to biostatistics. Wiley, Chichester, 2001), on variable transformation, and on tests on moments. The solution requires the transformation of categorical response variables into numeric variables and the breaking up of the original problem’s hypotheses into partial sub-hypotheses regarding the moments of the transformed variables. This type of problem is considered to be almost impossible to analyze within likelihood ratio tests, especially in the multivariate case (Wang in J Am Stat Assoc 91:1676–1683, 1996). A comparative simulation study is also presented along with an application example.     

A simple in-host model for Mycobacterium tuberculosis that captures all infection outcomes

ABSTRACT

Tuberculosis infection can result in clearance, latent infection, or active disease, with slow or fast progression. A four-dimensional model of in-host tuberculosis infection includes macrophages, T lymphocytes, tuberculosis bacteria, and their interactions. Changes in the infection rate, cell-mediated immunity rate, macrophage loss rate, and bacteria killing rate most affect disease outcomes. Simulations show that a periodic solution can occur. When the infected macrophage killing rate is constant, a backward bifurcation exists and the system is globally stable.     

Assessing an Adult Mental Health Clinic for Age-Related Issues

A community mental health clinic in an urban setting is the subject of an exploratory assessment to determine whether its 55 + patients are being treated according to the special diagnostic and treatment issues that tend to affect older people. Depression is found to be high on the list of diagnoses in this age group. As many as 40% of the group are considered to be at risk for suicide. The interrelationship of medical and psychological factors is emphasized. Sixty-two percent of those studied are determined to be socially isolated. Treatment techniques recommended in the literature for older patients are summarized, and it is determined that, while therapists at the clinic.have not been trained in geriatric psychology, many are instinctively utilizing these techniques. Recommendations are made for increased use of groupwork with older patients, inservice education for staff, attention to medical complications, improved outreach, and involvement of family.     

权数对CPI的结果影响程度定量分析

权数是影响CPI精度的重要因素之一,通过对基本分类价格指数计算中的权数缺失和高层级价格指数计算中权数滞后的影响进行了理论和实证分析,结果表明,利用将销售量作为权数的联合比法对基本分类价格指数进行计算可以大幅提高其精度;高层级价格指数计算所用权数的滞后性同样会降低CPI的精度,且主要存在高估CPI的系统性误差问题。