A theoretical distribution for mental test scores

The negative hypergeometric distribution of raw scores on mental tests is derived from certain assumptions relating to test theory. This result is checked empirically in a number of examples. Further derivations lead to the bivariate distribution of parallel tests which is also verified with actual data. The bivariate distribution of raw score and true score is also derived from a further assumption. This distribution is used to set confidence limits for true scores for persons with a given raw score.This work was supported in part by contract Nonr-2752(00) between the Office of Naval Research and Educational Testing Service. Reproduction in whole or in part for any purpose of the United States Government is permitted.     

Cutting scores and errors of measurement

Arguments for using multiple cutting scores are theoretically inapplicable when the selection measures are fallible. The effect of errors of measurement in altering the shape of some optimum selection regions is here investigated mathematically, with numerical illustrations, for the case of two selection variables.This work was supported by contract Nonr-2752(00) between the Office of Naval Research and Educational Testing Service. Reproduction in whole or in part for any purpose of the United States Government is permitted.     

Using the ADI-R to diagnose autism in preschool children

The use of an investigator-based interview (Autism Diagnostic Interview—Revised; ADI-R) in the diagnosis of 51 autistic and 43 nonautistic mentally handicapped preschool children of equivalent mental and chronological age is described. Significant differences occurred between the groups on every diagnostic subdomain from the DSM-IV/ICD-10 draft criteria, except specific aspects of stereotyped language, still relatively rare in these young children. All but one of the 51 children judged to be autistic by clinical observation and only two of the 30 nonautistic mentally handicapped children with mental ages of 18 months or higher met criteria for autism on an algorithm to DSM-IV/ICD-10 draft criteria. However, discrimination using domain totals between autistic and the 13 nonautistic, nonverbal mentally handicapped children with mental ages under 18 months was poor. Quality of social overtures to adults and peers, play, and unusual sensory behaviors and mannerisms continued to differentiate these two groups. The relevance of these findings to the diagnosis of autism in preschool children is discussed.     

Termination of parental rights: A neglected side effect of infant intervention programs

A significant proportion of infants receiving treatment in programs designed to prevent abuse and psychosocial disorders may be removed from the custody of their parents by social service agencies. In an effort to help distinguish those cases at risk for termination of parental rights (TPR), seven such cases were analyzed and compared to seven similar cases where TPR did not occur. All 14 cases were referred because of abuse/neglect, and were at risk for continued abuse. Results showed that TPR was most likely in families where the parents were viewed as being unpleasant, as having a poor relationship with their child, were seen as retarded by the social service agency, and whose infants showed large gains in developmental level, especially during foster placement. These findings were interpreted as indicating a mixture of actual lack of progress in treatment and a negative attitudinal set about these clients.     

Identification of self through olfaction

To study olfactory communication in humans, 100 undergraduates ranging from age 18 to 45 yr. wore freshly washed, identical T-shirts continuously for 24 hr. During this time, the participants did not bathe or shower or apply any scent producing substance to their bodies, i.e., deodorants, perfumes. Upon retrieval, each shirt was placed in an identical brown bag. In groups of 10, each participant attempted to identify the T-shirt he had worn the previous 24 hr. The task was administered separately for each individual so that no participants knew the choice by a previous colleague. Analysis shows that the participants were able to identify correctly their own shirts on the first try three-quarters of the time. Furthermore, sex, age, smoking habit of the participant, and menstrual cycle phase in the women were factors in successful outcomes.     

Directed Thinking and Readiness to Change Self‐Beneficial Behaviors: Are You Ready for Some Studying?

Previous research has suggested that intentions to engage in studying and other self-beneficial activities might be promoted more by thinking about actions one could take than by thinking about reasons for doing so. The present experiments assessed whether the relative efficacy of actions vs. reasons might depend on individuals' readiness to change. Consistent with previous findings on the processes of change most relevant in different stages, the benefits of self-generated actions were more pronounced for participants who were in the later stages of change. This \"matching-to-stage\" relationship occurred in 2 experiments that differed in stage measurement, how thinking was directed, and which outcomes were measured. The results have both practical and theoretical implications for attempts to change self-beneficial behaviors.