Robust tests for the common principal components model

When dealing with several populations, the common principal components (CPC) model assumes equal principal axes but different variances along them. In this paper, a robust log-likelihood ratio statistic allowing to test the null hypothesis of a CPC model versus no restrictions on the scatter matrices is introduced. The proposal plugs into the classical log-likelihood ratio statistic robust scatter estimators. Using the same idea, a robust log-likelihood ratio and a robust Wald-type statistic for testing proportionality against a CPC model are considered. Their asymptotic distributions under the null hypothesis and their partial influence functions are derived. A small simulation study allows to compare the behavior of the classical and robust tests, under normal and contaminated data.     

Isn’t that why you were hired?

Human service organizations seek bilingual professionals to meet the social and linguistic needs of their increasingly limited English proficient (LEP) clientele. As a result, bilingual professionals often find themselves having to meet overwhelming service delivery expectations. This paper reports on a qualitative study about the work experiences of 27 court employees within a judicial system in the Eastern United States. The study found that bilingual professionals encounter challenges because of their language skills. At the intersection of these challenges are microaggressions that manifest in the judicial system, adversely affecting them professionally and personally.     

The eigenstructure of block-structured correlation matrices and its implications for principal component analysis

Block-structured correlation matrices are correlation matrices in which the p variables are subdivided into homogeneous groups, with equal correlations for variables within each group, and equal correlations between any given pair of variables from different groups. Block-structured correlation matrices arise as approximations for certain data sets’ true correlation matrices. A block structure in a correlation matrix entails a certain number of properties regarding its eigendecomposition and, therefore, a principal component analysis of the underlying data. This paper explores these properties, both from an algebraic and a geometric perspective, and discusses their robustness. Suggestions are also made regarding the choice of variables to be subjected to a principal component analysis, when in the presence of (approximately) block-structured variables.     

Does alcohol consumption reinforce mental problems in adolescence?

The main goal of this article is to provide empirical evidence that alcohol consumption reinforces the occurrence of mental illnesses even at early stages of life. We control probit estimations for unobserved heterogeneity and endogeneity. We have drawn a sample of 73,024 individuals from the Spanish National Survey on Drug Use in the School Population (2000, 2002, 2004). Our results confirm our theoretical hypothesis that alcohol consumption has a negative influence on youth state of health, but the magnitude of this influence is lower once we controlled for unobserved heterogeneity and endogeneity. Gender differences reveal that females are more likely to have been prescribed tranquilizers, and they are also more vulnerable to alcohol consumption than males are. As effective instruments to improve young people well-being, we suggest increasing the price of liquors and a greater parental control in how their children spend their available budget, and more important, in how they feel.     

The Influence of Gender Equality on Volunteering Among European Senior Citizens

VOLUNTAS: International Journal of Voluntary and Nonprofit Organizations - This research analyzes how gender equality influences the participation of European senior citizens in a range of...     

Who Needs the Experts? The Politics and Practices of Alternative Humanitarianism and Its Relationship to NGOs

VOLUNTAS: International Journal of Voluntary and Nonprofit Organizations - Drawing on fieldwork in Greece, we examine the politics and practices of autonomous volunteering in the context of the...     

University Students’ Attitudes Toward Same-Sex Parenting and Gay and Lesbian Rights in Portugal

The purpose of this study was to explore university students’ attitudes toward same-sex parenting and toward gay and lesbian rights. A total of 292 participants, aged between 18 and 27 (M = 21) responded to a questionnaire measuring attitudes toward parenting by gay men and lesbians, gay and lesbian rights, and beliefs about the etiology of homosexuality. Results revealed that the majority of students were against gay and lesbian parenting, gay and lesbian equal rights, and believed that homosexuality has a social/environmental basis. It was found that sexual prejudice is highly prevalent in Portuguese university students, and implications of these findings are discussed.     

Personality and Subjective Well-Being: What Hides Behind Global Analyses?

The relation between personality and subjective well-being (SWB) remains involved in a considerable ambiguity and the numerous studies conducted have neglected an approach at a more detailed level of analysis. This study explores the idea that neuroticism, extraversion and conscientiousness facets predict differentially each SWB component. A battery of self-report questionnaires was used to assess personality and SWB in 398 teachers of primary and high schools. Findings of a cross-sectional study showed that neuroticism, extraversion and conscientiousness facets contributed to significantly explain the variance in positive affect, negative affect and life satisfaction. Moreover, these facets predicted differentially each of the three SWB components. At same time, this study corroborates two important premises: the specificity of facets as discrete traits and the independence of the three SWB components.