Stochastic ordering using the latent trait and the sum score in polytomous IRT models

In a restricted class of item response theory (IRT) models for polytomous items the unweighted total score has monotone likelihood ratio (MLR) in the latent trait. MLR implies two stochastic ordering (SO) properties, denoted SOM and SOL, which are both weaker than MLR, but very useful for measurement with IRT models. Therefore, these SO properties are investigated for a broader class of IRT models for which the MLR property does not hold.In this study, first a taxonomy is given for nonparametric and parametric models for polytomous items based on the hierarchical relationship between the models. Next, it is investigated which models have the MLR property and which have the SO properties. It is shown that all models in the taxonomy possess the SOM property. However, counterexamples illustrate that many models do not, in general, possess the even more useful SOL property.Hemker's research was supported by the Netherlands Research Council, Grant 575-67-034. Junker's research was supported in part by the National Institutes of Health, Grant CA54852, and by the National Science Foundation, Grant DMS-94.04438.     

Perfectionism and Suicide Ideation in Adolescent Psychiatric Patients

This study was conducted to examine the relations between dimensions of perfectionism and suicide ideation in an adolescent psychiatric sample. A sample of 66 adolescents from an inpatient psychiatric facility completed the Child and Adolescent Perfectionism Scale, the Child's Hopelessness Scale, and the Suicide Ideation Questionnaire. Overall, the results indicated that socially prescribed perfectionism was associated with greater suicide ideation and that it, along with hopelessness, accounted for unique variance in suicide ideation scores. The findings are discussed in terms of their practical and theoretical significance as well as their consistency with similar research with adults.     

The Patient Self-Determination Act and Advance Directives: Snapshots of Activities in a Tertiary Health Care Center

This study describes the results of a retrospective review of patients' charts who had an advanced directive (AD) and who were hospitalized in a tertiary, acute care teaching hospital. The purpose of the review was to understand from clinical, sociological, ethical and legal perspectives the nature and utility of ADs. Findings and implications of the review are discussed in terms of: patient demographics; diagnoses; quality of ADs; influence of ADs on clinical decisions; and legal aspects of ADs.     

Neural Network Models and Mechanisms of Strategy Development

The focus of this paper is mechanisms that may be responsible for intellectual and developmental differences in the cognitive strategies of typical and atypical children, including those with mental retardation. The discussion of these mechanisms is based on behavioral experiments on external memory strategies and on a set of neural network models designed for these tasks. Following the review of the external memory research, the rationale for using neural network models, how they have been used in other research, and their specific application to intellectual and developmental differences in external memory, including the results of several simulations, are reviewed. This is followed by a discussion of the mechanisms of intellectual differences and developmental change included in the models and some challenges for this type of modeling. Neural network modeling is discussed as an asset to research on cognitive development.     

Adaptiveness: A moderator of the adverse impact of hassles?

Adaptiveness constitutes coping consistently with Stressors so to reduce distress or, at worst, not aggravate it. Accordingly, it should moderate the adverse impact of hassles. Undergraduate volunteers (N = 200) responded to measures of hassles, adaptiveness, and the criteria of subjective distress, psychiatric symptomatology and minor physical ailments. In all three regression analyses, hassles made a substantial positive contribution and adaptiveness a small negative contribution to adverse outcome. The interaction between hassles and adaptiveness was non-significant in all three cases. Alternative interpretations were identified to guide further research.