An optional randomized response model for estimating a rare sensitive attribute using Poisson distribution

The crux of this article is to estimate the mean of the number of persons possessing a rare sensitive attribute based on the Mangat (1991 Mangat, N.S. (1991). An optional randomized response sampling technique using non–stigmatized attribute. Statistica. 51(4):595–602. [Google Scholar]) randomization device by utilizing the Poisson distribution in simple random sampling and stratified sampling. Properties of the proposed randomized response (RR) model have been studied along with recommendations. It is also shown that the proposed model is more efficient than that of Land et al. (2011 Land, M., Singh, S., Sedory, S.A. (2011). Estimation of a rare attribute using Poisson distribution. Statistics. 46(3):351–360.[Taylor &; Francis Online], [Web of Science ®] , [Google Scholar]) in simple random sampling and that of Lee et al. (2013 Lee, G.S., Uhm, D., Kim, J.M. (2013). Estimation of a rare sensitive attribute in stratified sampling using Poisson distribution. Statistics. 47(3):575–589.[Taylor &; Francis Online], [Web of Science ®] , [Google Scholar]) in stratified random sampling when the proportion of persons possessing a rare unrelated attribute is known. Numerical illustrations are also given in support of the present study.     

Improved estimation methods for unrelated question randomized response techniques

The randomized response technique (RRT) is an important tool, commonly used to avoid biased answers in survey on sensitive issues by preserving the respondents’ privacy. In this paper, we introduce a data collection method for survey on sensitive issues combining both the unrelated-question RRT and the direct question design. The direct questioning method is utilized to obtain responses to a non sensitive question that is related to the innocuous question from the unrelated-question RRT. These responses serve as additional information that can be used to improve the estimation of the prevalence of the sensitive behavior. Furthermore, we propose two new methods for the estimation of the proportion of respondents possessing the sensitive attribute under a missing data setup. More specifically, we develop the weighted estimator and the weighted conditional likelihood estimator. The performances of our estimators are studied numerically and compared with that of an existing one. Both proposed estimators are more efficient than the Greenberg's estimator. We illustrate our methods using real data from a survey study on illegal use of cable TV service in Taiwan.     

Pairwise comparisons of treatments with ordinal responses in a two-way setting

In clinical studies, pairwise comparisons are frequently performed to examine differences in efficacy between treatments. The statistical methods of pairwise comparisons are available when treatment responses are measured on an ordinal scale. The Wilcoxon–Mann–Whitney test and the latent normal model are popular examples. However, these procedures cannot be used to compare treatments in parallel groups (a two-way design) when overall type I error must be controlled. In this paper, we explore statistical approaches to the pairwise testing of treatments that satisfy the requirements of a two-way layout. The results of our simulation indicate that the latent normal approach is superior to the Wilcoxon–Mann–Whitney test. Clinical examples are used to illustrate our suggested testing methods.     

The effect of product-harm crisis situations on firms’ spokesperson strategies: Evidence from China's emerging market economy

The purpose of this paper is to examine the influence product-harm crisis situations have on, a firm's spokesperson strategies in China's emerging market economy. Through the content analysis of, 127 product-harm crises, crisis type is found to be a predictor of spokesperson strategies. Compared, with Chinese brands, foreign brands are less likely to employ top-executive spokesperson strategies, during product-harm crises. Crisis severity was found to have no impact on the adoption of, spokesperson strategies.     

高校经管类学生参与科研意愿的影响因素分析——基于安徽省8所高校的问卷调查

大学生参与科研是高校培养双创型人才的重要途径之一,高校经管类专业学生培养存在重理论、轻实践的现象。安徽省8所高校1406名经济管理类学生科研意愿的实证分析表明:年级、学习成绩、科研重要性认知、科研了解程度和学校科研活动开展对大学生科研意愿有显著影响。高校在经管类学生培养过程中应通过加强科研宣传推广、开设科研训练课程、丰富科研活动多样性、激励教师科研指导和开拓校外实践教学基地建设等措施增强学生参与科研的积极性,提升学生的双创能力。     

工科院校思想政治课教师职业倦怠探析

高校思想政治理论课是对大学生进行系统思想政治教育的主要渠道和主阵地。思政教师教育作用的发挥至为关键。但思政教师却弥漫着职业倦怠的气息。对教师自身、想政治理论课教学效果以及整个社会都产生负面的影响。现以工科院校思政教师为主体分析其职业倦怠的危害、成因,探讨预防及缓解对策。     

基于ANSYS的行李车改造成发电车的车架设计与分析

现代设计方法的发展和使用,使铁路车辆设计变得越来越快速高效。在行李车改造为发电车过程中,首先根据车架结构对车厢进行布局设计,其次运用有限元分析软件ANSYS对改造后的车辆车架系统从强度和刚度方面进行计算和分析。然后根据分析结果,使用APDL语言对车架薄弱环节和不合理结构进行改进。最后,对改造后车架进行模态分析和谐响应分析,确定有害频率和振型,并采取有效减振措施。从研究结果看,改造后的车辆车架能达到安全使用的设计目的。     

Improved randomized response in additive scrambling models

Randomized response models deal with stigmatizing variables appearing in health surveys. Additive and subtractive scrambling in split sample and double response yield unbiased mean and sensitivity estimators of high precision. The split sample method is protective of privacy. The double response method is as protective only conditionally. To achieve the maximum efficiency, the scrambling variables must be similar to each other and the probability of obtaining a true response must be as large as possible. The randomized response procedures yield more efficient estimates of the average total number of classes missed by university students.     

Identifying the most successful dose (MSD) in dose-finding studies in cancer

For a dose finding study in cancer, the most successful dose (MSD), among a group of available doses, is that dose at which the overall success rate is the highest. This rate is the product of the rate of seeing non-toxicities together with the rate of tumor response. A successful dose finding trial in this context is one where we manage to identify the MSD in an efficient manner. In practice we may also need to consider algorithms for identifying the MSD which can incorporate certain restrictions, the most common restriction maintaining the estimated toxicity rate alone below some maximum rate. In this case the MSD may correspond to a different level than that for the unconstrained MSD and, in providing a final recommendation, it is important to underline that it is subject to the given constraint. We work with the approach described in O'Quigley et al. [Biometrics 2001; 57(4):1018-1029]. The focus of that work was dose finding in HIV where both information on toxicity and efficacy were almost immediately available. Recent cancer studies are beginning to fall under this same heading where, as before, toxicity can be quickly evaluated and, in addition, we can rely on biological markers or other measures of tumor response. Mindful of the particular context of cancer, our purpose here is to consider the methodology developed by O'Quigley et al. and its practical implementation. We also carry out a study on the doubly under-parameterized model, developed by O'Quigley et al. but not