Estimation of coefficient of dispersion using auxiliary information

In this note, we consider the problem of estimation of coefficient of dispersion of a study variable by making use of known value of the coefficient of dispersion of an auxiliary variable. We propose ratio and regression-type estimators. We derive expressions of bias and variance of the proposed estimators to the first order of approximation. The relative efficiencies of the ratio and regression-type estimators with respect to the naïve estimator are investigated through a simulation study.     

Simultaneous estimation of means of two sensitive variables

In this paper, we introduce a new problem of simultaneous estimation of means of two quantitative sensitive variables by using only one randomized response another pseudo response from a respondent in a sample. The proposed estimators are extended to stratified random sampling, and the relative efficiency values are computed for equal, proportional, and optimum allocation with respect to the newly introduced naïve estimators.     

Educational inequality across three generations in Australia

The transfer of advantage and disadvantage across multiple generations is receiving increasing attention in the international literature; however, transfers of resources across multiple generations in Australian families are less well understood. Using a longitudinal dataset of Australian children, we have the opportunity to not only investigate the transfer of educational resources across three generations in Australia, but also investigate the gendered nature of these transfers, which has been a limitation of other studies. We find no evidence of individual grandparent education effects on numeracy and reading scores for grandchildren in Year 3, independent of parent educational attainment and other covariates. However, significant effects on numeracy and reading scores were observed for children in families where both the grandmother and grandfather in maternal and paternal grandparent sets had high educational attainment (a diploma or university qualification), and where either or both the mother and father had a university qualification. These results suggest that the contribution of grandparents to the academic achievement of grandchildren cannot be fully explained by the parent generation and that the concentration of human capital in families contributes to educational inequalities across multiple generations that can be observed by eight years of age.     

A decision-theoretical view of default priors

In this article, we outline a simple and intuitively appealing procedure to derive default priors. The main idea is to regard the choice of such a prior as a formal Bayesian decision problem. We also discuss Jeffreys prior and more generally the reference prior of Bernardo (J R Stat Soc B 41:113–147, 1979) from this standpoint.     

Theory and social work: A conceptual review of the literature

This article presents a conceptual review of the literature concerning social work and theory. Based on analysis of 93 research studies, drawn from literature in English published between 1968 and 2016, the review considers the many ways that theory is conceptualised in the literature, and asks meta‐theoretical questions about how and why different conceptualisations arise. The article examines definitional questions and ambiguities concerning the use of theory, extant research on the use of theory by social workers in practice, hostility expressed regarding theory in social work, the theory/practice divide and perspectives that emphasise theory's utility or functionality. The article points at some methodological and ethical limitations concerning current research, and summarises dominant, as well as less prominent, versions of what counts as theory within the social work discipline, before finally suggesting that further meta‐theoretical research is needed.     

A generalisation of T‐optimality for discriminating between competing models with an application to pharmacokinetic studies

The T‐optimality criterion is used in optimal design to derive designs for model selection. To set up the method, it is required that one of the models is considered to be true. We term this local T‐optimality. In this work, we propose a generalisation of T‐optimality (termed robust T‐optimality) that relaxes the requirement that one of the candidate models is set as true. We then show an application to a nonlinear mixed effects model with two candidate non‐nested models and combine robust T‐optimality with robust D‐optimality. Optimal design under local T‐optimality was found to provide adequate power when the a priori assumed true model was the true model but poor power if the a priori assumed true model was not the true model. The robust T‐optimality method provided adequate power irrespective of which model was true. The robust T‐optimality method appears to have useful properties for nonlinear models, where both the parameter values and model structure are required to be known a priori, and the most likely model that would be applied to any new experiment is not known with certainty. Copyright © 2012 John Wiley & Sons, Ltd.     

Epidemic Potential of Measles and Rubella

Abstract

Although there have been major declines in the incidence of measles and rubella in the United States since licensure of vaccines, the incidence of disease in adolescents and young adults has not declined nearly as markedly as that in younger children. As a result, an increasing proportion of cases have occurred in adolescents and young adults. In 1978, 26% of all reported measles cases in which age was known occurred in those 15 years of age and older, and 76% reported rubella cases occurred in this age group. Outbreaks of both diseases have been reported from high schools, military bases, colleges, and universities. During a recent outbreak of measles involving a university, a 22-year-old university employee contracted measles and died of measles encephalitis. In addition to the direct effects of these diseases, the implications of the current pattern of occurrence of two infections known to have adverse effects on the developing fetus are obvious.

Improvements in immunization levels and declines in disease incidence have been brought about effectively by the enactment and enforcement of immunization requirements for school-age children and military recruits. Colleges and universities should also institute immunization requirements as a condition of enrollment.     

The spatial distribution of smoking violations on a no-smoking campus: Implications for prevention

ABSTRACT

Objective: The present study extends research on campus smoking bans by examining where smokers are violating the policy at a large university in the southeastern region of the United States. Participants: The data collection was conducted by one graduate student from the university in August of 2014. Methods: A global positioning system device was used to collect the geo-coordinates of littered cigarette butts as a proxy measure for smoking violations. Results: A hot spot analysis found a number of spatial concentrations on campus, largely around classroom and administrative buildings along with parking lots and garages. Conclusions: The implications of such findings can direct enforcement to target these areas in order to reduce offenses and fulfill the initial goals of policy-makers and university administrators who support smoke-free campuses.