Resolution of Godambe's paradox

Two versions of a statistical paradox involving an ancillarity principle have recently been proposed by Godambe (1979, 1982). In this note, we point out that the two versions of his paradox are actually quite different, and we resolve both of them by investigating their relationship to randomization. The first version of Godambe's paradox was criticized earlier by Good (1980), but we believe his argument to be flawed.     

Bootstrap adaptive estimation: The trimmed-mean example

We consider the problem of choosing among a class of possible estimators by selecting the estimator with the smallest bootstrap estimate of finite sample variance. This is an alternative to using cross-validation to choose an estimator adaptively. The problem of a confidence interval based on such an adaptive estimator is considered. We illustrate the ideas by applying the method to the problem of choosing the trimming proportion of an adaptive trimmed mean. It is shown that a bootstrap adaptive trimmed mean is asymptotically normal with an asymptotic variance equal to the smallest among trimmed means. The asymptotic coverage probability of a bootstrap confidence interval based on such adaptive estimators is shown to have the nominal level. The intervals based on the asymptotic normality of the estimator share the same asymptotic result, but have poor small-sample properties compared to the bootstrap intervals. A small-sample simulation demonstrates that bootstrap adaptive trimmed means adapt themselves rather well even for samples of size 10.     

Worldwide research output in probability and statistics: An update

The authors update the work of Genest (1997, 1999) on world research output in probability and statistics. The rankings they produce of countries and institutions are based on a survey of papers published between 1986 and 2000 in 25 specialized journals of high reputation in these two fields. The contribution of Canadian probabilists and statisticians is highlighted.     

Gender differences of psychological abuse in high school dating relationships

It is becoming increasingly evident that physical abuse is often accompanied by psychological abuse in marital as well as college dating relationships. However, no known research has been conducted to examine psychological abuse in the high school population, nor have gender differences been explored in relationship to psychological abuse of high school students. For this study, the Psychological Maltreatment of Women Inventory (PMWI) has been modified so that it could explore the experiences of psychological abuse of 736 male and female respondents from a large Midwest school.T-tests were performed to examine gender differences of overall and individual scores of psychological abuse. Loglinear analysis was used to examine relationships between psychological abuse, severity of physical abuse and stage of the dating relationship. Results indicated that overall, there was little psychological abuse occurring in high school dating relationships, but detected six items of specific gender differences. It was found that dating couples were likely to experience significantly more psychological abuse in relationships where severe physical violence was occurring. No significant interactions were found between psychological abuse, gender, and the various stages of the dating relationship, i.e. casual dating, serious dating. Although overall, minimal psychological abuse was found, regression analysis indicated a significant relationship between total physical violence and six individual psychological abuse items. Findings are compared to the literature on college dating violence and marital abuse.     

Goodness-of-fit Tests for Mixed Models

Abstract.  Mixed linear models have become a very useful tool for modelling experiments with dependent observations within subjects, but to establish their appropriateness several assumptions have to be checked. In this paper, we focus on the normality assumptions, using goodness-of-fit tests that make allowance for possible design imbalance. These tests rely on asymptotic results, which are established via empirical process theory. The power of the tests is explored empirically, and examples illustrate some aspects of the usage of the tests.     

The Development of Theory and Treatment with Substance Abusing Female Juvenile Offenders

Little is known regarding the specific treatment needs of those female juvenile offenders with a history of substance abuse. While social scientists have advanced distinct theories regarding adolescent substance use and juvenile delinquency, minimal work has been conducted to integrate or link these two. In attempting to further explore their interrelationships, this article will review and incorporate the relevant theoretical and practice milestones in three areas: (1) substance abuse and women, (2) substance abuse and adolescents, and (3) substance abuse and juvenile delinquency, leading to the development of new theory and practice relevant to the female substance abusing juvenile offender population. The authors propose some practice considerations for current interventions with this population and discuss implications for future research and exploration.