On perfect simulation for some mixtures of distributions

This paper studies the implementation of the coupling from the past (CFTP) method of Propp and Wilson (1996) in the set-up of two and three component mixtures with known components and unknown weights. We show that monotonicity structures can be exhibited in both cases, but that CFTP can still be costly for three component mixtures. We conclude with a simulation experiment exhibiting an almost perfect sampling scheme where we only consider a subset of the exhaustive set of starting values.     

Life satisfaction in midlife childless and empty-nest men and women

The primary purpose of this study was to contrast the life satisfaction of midlife empty-nest and childless individuals. Seventy-two men and women reported on their satisfaction with 11 areas of life as well as with regard to children. Empty-nest individuals were more satisfied than childless persons with regard to their decisions regarding children; however, the childless individuals were not unhappy with their decisions. Empty-nest individuals were also more positive than childless individuals about contact with children. There were no differences between the two groups with regard to areas of life satisfaction not related to children; nor were there significant gender differences in life satisfaction. The results were discussed in relation to both theory and data concerning midlife satisfaction and adjustment.SMS AssociatesThe research was completed by James E. Bell in partial fulfillment of the requirement for the masters of counseling degree at Arizona State University.     

Impact of methods for reducing respondent burden on personal network structural measures

We examine methods for reducing respondent burden in evaluating alter–alter ties on a set of network structural measures. The data consist of two sets, each containing 45 alters from respondent free lists: the first contains 447 personal networks, and the second 554. Respondents evaluated the communication between 990 alter pairs. The methods were (1) dropping alters from the end of the free-list, (2) randomly dropping alters, (3) randomly dropping links, and (4) predicting ties based on transitivity. For some measures network structure is captured with samples of less than 20 alters; other measures are less consistent. Researchers should be aware of the need to sample a minimum number of alters to capture structural variation.     

'I made some mistakes . . . but I love them dearly' the views of parents of children in informal kinship care

In-depth semi-structured interviews with 30 parents of children living with relatives in informal kinship care arrangements revealed the parents' views of the reasons for the informal kinship care arrangements, quality of their relationships with the children and their caregivers, their current and future roles in their children's lives, feelings experienced when with and away from the children, positive and negative aspects of kinship care, future goals and dreams for their children, and their assessments of their own strengths and challenges. Results of these interviews suggest several implications for social work practice and research.     

The social stratification of tongue shape for postvocalic /r/ in Scottish English1

The sociolinguistic modelling of phonological variation and change is almost exclusively based on auditory and acoustic analyses of speech. One phenomenon which has proved elusive when considered in these ways is the variation in postvocalic /r/ in Scottish English. This study therefore shifts to speech production: we present a socioarticulatory study of variation of postvocalic /r/ in CVr (e.g. car) words, using a socially‐stratified ultrasound tongue imaging corpus of speech collected in eastern central Scotland in 2008. Our results show social stratification of /r/ at the articulatory level, with middle‐class speakers using bunched articulations, while working‐class speakers use greater proportions of tongue‐tip and tongue‐front raised variants. Unlike articulatory variation of /r/ in American English, the articulatory variants in our Scottish English corpus are both auditorily distinct from one another, and correlate with strong and weak ends of an auditory rhotic continuum, which also shows clear social stratification.     

Conflict of Interest in Theories of Organization: Herbert A. Simon and Oliver E. Williamson

Journal of Management and Governance -     

P-value adjustment for multiple binary endpoints

The p-value-based adjustment of individual endpoints and the global test for an overall inference are the two general approaches for the analysis of multiple endpoints. Statistical procedures developed for testing multivariate outcomes often assume that the multivariate endpoints are either independent or normally distributed. This paper presents a general approach for the analysis of multivariate binary data under the framework of generalized linear models. The generalized estimating equations (GEE) approach is applied to estimate the correlation matrix of the test statistics using the identity and exchangeable working correlation matrices with the model-based as well as robust estimators. The objectives of the approaches are the adjustment of p-values of individual endpoints to identify the affected endpoints as well as the global test of an overall effect. A Monte Carlo simulation was conducted to evaluate the overall family wise error (FWE) rates of the single-step down p-value adjustment approach from two adjustment methods to three global test statistics. The p-value adjustment approach seems to control the FWE better than the global approach Applications of the proposed methods are illustrated by analyzing a carcinogenicity experiment designed to study the dose response trend for 10 tumor sites, and a developmental toxicity experiment with three malformation types: external, visceral, and skeletal.     

Tests for symmetry about an unknown value based on the empirical distribution function

A class of Kolmogorov-Smirnov and Cramér-von Mises type statistics for testing symmetry about an unknown value is described. These statistics are not distribution-free, however, and, indeed, are not readily amenable to calculation. A linear rank statistic analog of the first component of the Cramér-von Mises type statistic is investigated. Asymptotic non-null properties of these procedures in the normal case are studied, and an efficiency comparison of the Cramér-vonMises statistic, the linear rank statistic analog, the modified Wil-coxon statistic, and the likelihood ratio test is reported.