Estimating true score in the compound binomial error model

Several procedures have been proposed in the statistical literature for estimating simultaneously the mean of each ofk binomial populations. In terms of mental test theory, however, it is not clear that these procedures should be used when an item sampling model applies since the binomial error model is usually viewed as an oversimplification of the true situation. In this study we compare empirically several of these estimation techniques. Particular attention is given to situations where observations are generated according to a two-term approximation to the compound binomial distribution.The author would like to thank Shelley Niwa for writing the computer programs used in this study.The work upon which this publication is based was performed pursuant to Grant # NIE-G-76-0083 with the National Institute of Education, Department of Health, Education and Welfare. Points of view or opinions stated do not necessarily represent official NIE position or policy.     

A lower bound to the probability of choosing the optimal passing score for a mastery test when there is an external criterion

Recently there has been interest in the problem of determining an optimal passing score for a mastery test when the purpose of the test is to predict success or failure on an external criterion. For the case of constant losses for the two error types, a method of determining an optimal passing score is readily derived using standard techniques. The purpose of this note is to describe a lower bound to the probability of identifying an optimal passing score based on a random sample ofN examinees.The work upon which this publication is based was performed pursuant to a grant [contract] with the National Institute of Education, Department of Health, Education and Welfare. Points of view or opinions stated do not necessarily represent official NIE position or policy.     

Pregnancy: A social stigma?

Experimental evidence is presented which explores the social stimulus value of pregnancy. It was found that, for men especially, the pregnant woman elicits avoidance and staring and that these responses occur primarily because pregnancy is a novel visual stimulus. For women, avoidance seems to be tied less to the stimulus aspects of the pregnant woman than to role expectations about her behavior. The pregnant woman is expected to be passive, but is simultaneously rejected for being so. It is argued that this constellation of responses may produce discomfort and withdrawal in the pregnant woman herself, since avoidance and staring are easily interpreted as negative reactions. How these reactions fit into the cultural response to pregnancy is discussed.     

Catholics and the Christian Right: A View from Four States

Christian Right Organizations in the 1990s have tried to avoid the pitfalls for the religious particularism that undermined the earlier efforts of such groups as Moral Majority to build long lasting political coalitions. For many Christian Right leaders, conservative Catholics appear to be a particularly appealing group to reach for membership recruitment and political coalition-building. Yet such leading groups as the Christian Coalition have largely experienced disappointment with such efforts.
This essay presents data that offer reasons why conservative Catholics might be willing to form political coalitions with activists of the Christian Right but remain reluctant to join Christian Right organizations. The findings are based on a large survey of Republican party state convention delegates in four states. The data show that Catholic delegates hold very conservative issue positions in line with Christian Right organizations, and have positive feelings toward Christian Right leaders and organizations. Yet Catholic delegates hold somewhat distinctive positions among Republicans on certain issues, and therefore remain reluctant to join the Christian Coalition and other such groups.     

Cross-National Variations in Behavioral Profiles Among Homeless Youth

Cross-national comparisons of homeless youth in Melbourne, Australia, and Los Angeles, CA, United States were conducted. Newly (n = 427) and experienced (n = 864) homeless youth were recruited from each site. Compared to Australia, homeless youth in the United States were younger, more likely to be in school or jail, demonstrated fewer sexual and substance use risk acts, fewer suicidal acts, and reported less need for social services. Across sites, experienced homeless youth were more likely to be older, male, engage in sexual and substance use, report greater need for social services, and make greater use of work, substance use, and health-related services. Homeless youth have different behavioral profiles in Australia and the United States, reflecting differences in the effectiveness of service systems in the two countries in keeping youth with fewer problems out of homelessness.     

Pairwise comparisons of trimmed means for two or more groups

The paper takes up the problem of performing all pairwise comparisons amongJ independent groups based on 20% trimmed means. Currently, a method that stands out is the percentile-t bootstrap method where the bootstrap is used to estimate the quantiles of a Studentized maximum modulus distribution when all pairs of population trimmed means are equal. However, a concern is that in simulations, the actual probability of one or more Type I errors can drop well below the nominal level when sample sizes are small. A practical issue is whether a method can be found that corrects this problem while maintaining the positive features of the percentile-t bootstrap. Three new methods are considered here, one of which achieves the desired goal. Another method, which takes advantage of theoretical results by Singh (1998), performs almost as well but is not recommended when the smallest sample size drops below 15. In some situations, however, it gives substantially shorter confidence intervals.