Race-Ethnicity and Health Trajectories: Tests of Three Hypotheses across Multiple Groups and Health Outcomes

Racial-ethnic disparities in static levels of health are well documented. Less is known about racial-ethnic differences in age trajectories of health. The few studies on this topic have examined only single health outcomes and focused on black-white disparities. This study extends prior research by using a life course perspective, panel data from the Health and Retirement Study, and multilevel growth curve models to investigate racial-ethnic differences in the trajectories of serious conditions and functional limitations among blacks, Mexican Americans, and whites. We test three hypotheses on the nature of racial-ethnic disparities in health across the life course (aging-as-leveler, persistent inequality, and cumulative disadvantage). Results controlling for mortality selection reveal that support for the hypotheses varies by health outcome, racial-ethnic group, and life stage. Controlling for childhood socioeconomic status, adult social and economic resources, and health behaviors reduces but does not eliminate racial-ethnic disparities in health trajectories.     

Not Threats,but Resources: An Investigation of How Leaders React to Employee Constructive Voice

This research aims to investigate whether or not leaders, one of the main recipients of employee voice, develop good relationships with those who speak up. Drawing on resource theory and social exchange theory, we contend that constructive voice provides both information and affect resources to the leader, which in turn promote a resource-based exchange relationship with the leader (i.e., leader–member exchange; LMX). We further propose that leaders with an originality cognitive style are more likely to capture the resource value of constructive voice, while leaders who closely follow rules might not view constructive voice in a positive way, thus affecting their LMX relationships with the focal employee. Through a two-wave field survey among 199 leader–follower dyads (Study 1) and a vignette-based experiment among 221 leaders (Study 2), we found that leaders, especially leaders who advocated high originality, developed high-quality LMX relationships with those who engaged in constructive voice due to their perceptions of affect but not information resource.     

Hold or sell? How capital gains taxation affects holding decisions

Investments with exit flexibility require decisions regarding both the investment and holding period. Because selling an investment often leads to taxable capital gains, which crucially depend on the duration of an investment, we investigate the impact of capital gains taxation on exit timing under different tax systems. We observed that capital gains taxation delays exit decisions but loses its decision relevance for very long holdings. Often the optimal exit time, which indicates the maximal present value of future cashflows, cannot be determined analytically. However, we identify the breakeven exit time that guarantees present values exceeding those of an immediate sale. While, after-taxes, an immediate sale is often optimal, long holding periods might also be attractive for investors depending on the degree of income and corporate tax integration. A classic corporate tax system often indicates holdings over more than 100 periods. By contrast, a shareholder relief system indicates the earliest breakeven exit time and thus the highest level of exit timing flexibility. Surprisingly, high retention rates are likely to accelerate sales under a classic corporate system. Additionally, the worst exit time, which should be avoided by investors, differs tremendously across tax systems. For an integrated tax system with full imputation, the worst time is reached earlier than under partial or non-integrated systems. These results could help to predict investors’ behavior regarding changes in capital gains taxation and thus are of interest for both investors and tax policymakers. Furthermore, the results emphasize the need to control for the underlying tax system in cross-country empirical studies.     

A statistical model for orientation mechanism

A variance components model with response variable depending on both fixed effects of explanatory variables and random components is specified to model longitudinal circular data, in order to study the directional behaviour of small animals, as insects, crustaceans, amphipods, etc. Unknown parameter estimators are obtained using a simulated maximum likelihood approach. Issues concerning log-likelihood variability and the related problems in the optimization algorithm are also addressed. The procedure is applied to the analysis of directional choices under full natural conditions ofTalitrus saltator from Castiglione della Pescaia (Italy) beaches.     

The Statistics Bill: the Treasury's view

The bill for the independence of the official statistical system received its final reading in the House of Lords on 20th July, just as this edition of Significance went to press. In this article, Angela Eagle , the new Exchequer Secretary to the Treasury, sets out the official view of what this legislation, and associated developments, should mean for statisticians and users of statistics. She looks in particular at how the reforms could raise statistical quality. (An article setting out the Royal Statistical Society's view of the legislation will appear in the next issue.)     

The independent factor analysis approach to latent variable modelling

Independent factor analysis (IFA) has recently been proposed in the signal processing literature as a way to model a set of observed variables through linear combinations of latent independent variables and a noise term. A peculiarity of the method is that it defines a probability density function for the latent variables by mixtures of Gaussians. The aim of this paper is to cast the method into a more rigorous statistical framework and to propose some developments. In the first part, we present the IFA model in its population version, address identifiability issues and draw some parallels between the IFA model and the ordinary factor analysis (FA) one. Then we show that the IFA model may be reinterpreted as an independent component analysis-based rotation of an ordinary FA solution. We also give evidence that the IFA model represents a special case of mixture of factor analysers. In the second part, we address inferential issues, also deriving the standard errors for the model parameter estimates and providing model selection criteria. Finally, we present some empirical results on real data sets.     

Nonparametric rank-based test procedures for non-additive models in the two-way layout I. no replications

One of the major unresolved problems in the area of nonparametric statistics is the need for satisfactory rank-based test procedures for non-additive models in the two-way layout, especially when there is only one observation on each combination of the levels of the experimental factors. In this paper we consider an arbitrary non-additive model for the two-way layout with n levels of each factor. We utilize both alignment and ranking of the data together with basic properties of Latin squares to develop rank tests for interaction (non-additivity). Our technique involves first aligning within one of the main effects, ranking within the other main effects (columns and rows) and then adding the resulting ranks within “interaction bands” corresponding to orthogonal partitions of the interaction for the model, as denoted by the letters of an n × n Latin square. A Friedman-type statistic is then computed on the resulting sums. This is repeated for each of (n?1) mutually orthogonal Latin squares (thus accounting for all the interaction degrees of freedom). The resulting (n?1) Friedman-type statistics are finally combined to obtain an overall test statistic. The necessary null distribution tables for applying the proposed test for non-additivity are presented and we discuss the results of a Monte Carlo simulation study of the relative powers of this new procedure and other (parametric and nonparametric) procedures designed to detect interaction in a two-way layout with one observation per cell.     

Recruitment and Retention in a Parenting Intervention: A Case Study with Parents Aging Out of the Child Welfare System

ABSTRACT

Parenting interventions are efficacious in reducing child maltreatment and negative child behaviors, yet the recruitment and retention of parents, especially vulnerable parents, in such interventions can be challenging. Prior research identifies several ways to improve recruitment and retention including laying the foundation for the intervention, fostering relationships with parents, ensuring fit of the intervention with the intended population, and identifying barriers to parents’ participation. This case study presents a process of recruiting and retaining a vulnerable group of parents, specifically parenting youth aging out of the child welfare system. In addition to outlining the strategies used, lessons learned are highlighted. Parents expressed interest in the parenting intervention, experienced significant needs, negotiated great instability in their lives, and valued the social connections facilitated by the group intervention. Despite the research team following best practices and investing significant time and resources, recruitment and retention remained challenging. Implications for future work in this area are presented.     

Living with racism in education and society: Derrick Bell’s ethical idealism and political pragmatism

Derrick Bell’s pronouncement and challenge that racism is likely permanent has captured the imagination of Critical Race Theorists in education. Equally important are his ideas about living with the concrete conditions of racism. This article focuses on a tension within Bell’s work. On the one hand, his writings are characterized by a certain ‘racial realism.’ In this perspective, Bell encourages race scholars and activists to abandon notions of one day ending racism. On the other hand, Bell also retains a certain idealism, most evident in his appeal to the ethical dimensions of critical race work. He invites intellectuals to join him in fighting racism even if the prospects for change are sometimes bleak. In his life as well as his work, Bell willingly sacrificed prestige and financial security for his ideals, and seemed puzzled when his friends and colleagues were reluctant to do the same. Bell’s racial realism and ethical idealism comprise two – sometimes warring – moments that permeate his work.