An investigation of the sampling distributions of item discrimination indices

The sampling properties of four item discrimination indices (biserialr, Cook's indexB, theU–L 27 per cent index, and DeltaP) were investigated in order to ascertain their sampling properties when small samples drawn from actual test data rather than constructed data were employed. The empirical results indicated that the mean index values approximated the population values and that values of the standard deviations computed from large sample formulas were good approximations to the standard deviations of the observed distributions based on samples of size 120 or less. Goodness of fit tests comparing the observed distributions with the corresponding distribution of the product-moment correlation coefficient based upon a bivariate normal population indicated that this correlational model was inappropriate for the data. The lack of adequate mathematical models for the sampling distributions of item discrimination indices suggests that one should avoid indices whose only real reason for existence was the simplification of computational procedures.This research reported herein was performed pursuant to a contract (OE-2-10-071) with the United States Office of Education, Department of Health, Education and Welfare.     

Defaults in update semantics

The aim of this paper is twofold: (i) to introduce the framework of update semantics and to explain what kind of semantic phenomena may successfully be analysed in it: (ii) to give a detailed analysis of one such phenomenon: default reasoning.     

Commonalities and differences in similarity comparisons

Similarity is a central component of many cognitive processes. Current research suggests that similarity is well characterized as a comparison of structured representations. This process yields commonalities, differences related to the commonalities (alignable differences), and differences not related to the commonalities (nonalignable differences). In the first study, further evidence for this tripartite distinction is provided in a commonality and difference listing study involving pairs of pictures. This study indicates that alignable differences rather than nonalignable differences are central to the comparison process by virtue of their connection to the commonalities. The second study further demonstrates that alignable differences count more against the similarity of a pair than do nonalignable differences. We end by discussing implications of the distinction between alignable and nonalignable differences for other cognitive processes involving comparisons.     

Racial Categorization and Stereotype-Based Judgments About Homeless People1

The present study uses a social-cognitive paradigm to examine the association between racial categorization and stereotype-based judgments about homeless people. The study uses data from a national White subsample (N= 1,221) surveyed about attitudes toward homeless/homeless mentally ill people. It was hypothesized that individual differences in perceptions of the representativeness of Blacks in the homeless population, as measured by subjective estimates of the percentage of Blacks, would be associated with the enhancement of racially relevant negative stereotypes about homeless people. A secondary hypothesis was that perceptions of the representativeness of Blacks would be more strongly associated with the stereotype of homeless people as dangerous than with the view of them as lazy. The results support these hypotheses.     

TEACHING MULTIPLICATION FACTS TO STUDENTS WITH LEARNING DISABILITIES

Multiple baseline designs were used to examine the effects of an instructional package on accuracy of performance in solving multiplication facts by 3 students with learning disabilities. The instructional package included the following components: (a) a modified instructional sequence in which multiplication facts were grouped into the zeros, ones, doubles, fives, and nines categories, and those remaining; (b) identification of the category in which each fact belonged; (c) mnemonic strategies associated with solving facts in each category; and (d) steps to be completed for solving facts in each category. Results indicated that the instructional package produced substantial and immediate effects. After receiving instruction, a participant's accuracy was often 100%, and this was maintained throughout the evaluation even as other strategies were introduced. Comparable results occurred across students, demonstrating replication of the effects of the instructional package.     

Compassion: An east‐west comparison

Compassion is an emotion that occupies a central position in Mahāyāna Buddhist philosophy while it is often a neglected subject in contemporary western philosophy. This essay is a comparison between an Eastern view of compassion based upon Mahāyāna Buddhist perspectives and a western view of the same emotion. Certain principles found in Mahāyāna Buddhist philosophy such as the Bodhisattva Ideal, and suffering (dukkha) to name two, are explored for the information they contain about compassion. An essay by Lawrence Blum is taken as representative of a Western view (but not exclusively) and it is analyzed for its shortcomings in light of the Buddhist view. The conclusion briefly describes the value of understanding an eastern view on compassion as a means of filling the void one finds in western medical ethics discourse which focuses so heavily, and redundantly, upon issues such as patient autonomy and paternalism.     

Controversies over integrity testing: Two viewpoints

In the August 1993 issue ofJournal of Applied Psychology, Deniz Ones, Vish Viswesvaran, and Frank Schmidt published a monograph on the validity of integrity tests as revealed by meta-analysis. They concluded that integrity tests have substantial and generalizable predictive validity for criteria of both overall job performance and counterproductive behaviors on the job (e.g., disciplinary problems, absenteeism, rule breaking, violence on the job, theft, etc.). During the Fall of 1992, the authors sent a preprint of this study to David Lykken of the University of Minnesota, stimulating the exchange of letters that is reproduced here. The doubts, concerns, and feelings about integrity tests expressed by Professor Lykken are likely to be shared by others. The responses by Professors Schmidt, Ones, and Viswesvaran attempt to show that these worries are unfounded.