Heteroscedastic Global Tests that the Regression Parameters for Two or More Independent Groups are Identical

Simulation results are reported on methods that allow both within group and between group heteroscedasticity when testing the hypothesis that independent groups have identical regression parameters. The methods are based on a combination of extant techniques, but their finite-sample properties have not been studied. Included are results on the impact of removing all leverage points or just bad leverage points. The method used to identify leverage points can be important and can improve control over the Type I error probability. Results are illustrated using data from the Well Elderly II study.     

Field of study variation throughout the college pipeline and its effect on the earnings gap: Differences between ethnic and immigrant groups in Israel

This study demonstrates the analytical leverage gained from considering the entire college pipeline—including the application, admission and graduation stages—in examining the economic position of various groups upon labor market entry. The findings, based on data from three elite universities in Israel, reveal that the process that shapes economic inequality between different ethnic and immigrant groups is not necessarily cumulative. Field of study stratification does not expand systematically from stage to stage and the position of groups on the field of study hierarchy at each stage is not entirely explained by academic preparation. Differential selection and attrition processes, as well as ambition and aspirations, also shape the position of ethnic groups in the earnings hierarchy and generate a non-cumulative pattern. These findings suggest that a cross-sectional assessment of field of study inequality at the graduation stage can generate misleading conclusions about group-based economic inequality among workers with a bachelor’s degree.     

‘I nearly lost my work’: chance encounters,legal empowerment and the struggle for disability rights in Ghana

This article uses a case study from Ghana to argue that rights-based legal instruments are important but insufficient steps towards securing disability rights in non-western societies. Despite Ghana’s implementation of a Disability Act and ratification of the United Nations Convention on the Rights of Persons with Disabilities, a grassroots perspective shows that legislation and the model of legal empowerment will not automatically produce equal access to human rights. The paper will present this argument through a case study of an individual who became disabled in 2008 and struggled for four years to secure his rights to healthcare and employment. I also argue that the case has a wider significance for disability rights in Ghana and beyond.     

A volume based approach to establish B-spline based expressions for density functions and its application to progressive hybrid censoring

We propose an approach to determine the distribution of particular linear combinations of hybrid censored order statistics which is based on the calculation of volumes of polytopes. For this purpose, we establish efficient and compact volume formulas in terms of B-splines. Further, we illustrate our approach for ten different progressive hybrid censoring schemes under an exponential assumption.     

Simultaneous estimation and inference for multiple response variables

Multivariate data arise frequently in biomedical and health studies where multiple response variables are collected across subjects. Unlike a univariate procedure fitting each response separately, a multivariate regression model provides a unique opportunity in studying the joint evolution of various response variables. In this paper, we propose two estimation procedures that improve estimation efficiency for the regression parameter by accommodating correlations among the response variables. The proposed procedures do not require knowledge of the true correlation structure nor does it estimate the parameters associated with the correlation. Theoretical and simulation results confirm that the proposed estimators are more efficient than the one obtained from the univariate approach. We further propose simple and powerful inference procedures for a goodness-of-fit test that possess the chi-squared asymptotic properties. Extensive simulation studies suggest that the proposed tests are more powerful than the Wald test based on the univariate procedure. The proposed methods are also illustrated through the mother’s stress and children’s morbidity study.     

路演中董事长面部表情与IPO后公司业绩变脸

投资者是否可以利用“软”信息来识别公司的真实价值?社会心理学理论认为人在提供虚假信息(如撒谎)的时候会流露出负面情绪,进而反映到面部表情上。论文以2009年至2014年在创业板上市的公司为样本,分析公司上市后的业绩变脸幅度与其董事长在IPO路演讲话时的负面情绪水平之间的关系。为了提高结论的可靠性,本研究首先基于实验室实验方法设计欺骗行为实验,检验了Facereader软件测量面部表情给出的负面情绪值与欺骗行为之间的相关性。本研究指出可以利用董事长在IPO路演讲话的面部表情来识别公司的真实价值,该结论为保护投资者利益提供了一条新的途径。     

When difference creates dissonance: understanding the ‘engine’ of intercultural learning in study abroad

Why do some study abroad students improve their intercultural skills, while others revert to less sophisticated ways of making sense of cultural difference? Both intercultural competence theory and transformative learning theory attempt to explain why student intercultural learning occurs, but they only provide partial answers. Building on our previous study assessing intercultural competence in a 2015 field school in India, this article applies the concept of cognitive dissonance to explain the process behind intercultural learning. In the context of study abroad, students experience cognitive dissonance when they encounter cultural differences or similarities that confound previously held expectations about culture. Adapting Maertz, Hassan, and Magnusson’s cognitive dissonance resolution framework, we employ qualitative analysis of students’ written reflections to show how the resolution of cognitive dissonance could act as the ‘engine’ of intercultural learning.     

Similar coefficient for cluster of probability density functions

In this article, we propose a new criterion to evaluate the similarity of probability density functions (pdfs). We call this the criterion on similar coefficient of cluster (SCC) and use it as a tool to deal with overlap coefficients of pdfs in normal standard on [0;1]. With the support of the self-update algorithm for determining the suitable number of clusters, SCC then becomes a criterion to establish the corresponding cluster for pdfs. Moreover, some results on determination of SCC in case of two and more than two pdfs as well as relations of different SCCs and other measures are presented. The numerical examples in both synthetic data and real data are given not only to illustrate the suitability of proposed theories and algorithms but also to demonstrate the applicability and innovation of the proposed algorithm.     

Legitimating the Philippines as a language learning space: Transnational Korean youth's experiences and evaluations

This paper examines how a peripheral English‐speaking country is constructed as a legitimate language learning space in the global English language teaching (ELT) industry by investigating South Koreans’ recent engagement in Philippine English education. It focuses on a short‐term English study abroad program, in which the Philippines serves as a transit place prior to students’ moving to a Western English‐speaking country. Drawing data from ethnographic research on South Korean youth studying English abroad, the article analyzes why Korean students seek Philippine English education in spite of their apparent pursuit of authentic English, and how they evaluate their learning experience in the Philippines. This paper finds that the Philippines holds a niche market in the global ELT industry by separating a space for English learning from other public and everyday spaces of English use and offering pedagogically intensive but emotionally supportive environments to English learners.