Statistical simulation on microcomputers

The statistical simulation program DATASIM is designed to conduct large-scale sampling experiments on microcomputers. Monte Carlo procedures are used to investigate the Type I and Type II error rates for statistical tests when one or more assumptions are systematically violated-assumptions, for example, regarding normality, homogeneity of variance or covariance, mini-mum expected cell frequencies, and the like. In the present paper, we report several initial tests of the data-generating algorithms employed by DATASIM. The results indicate that the uniform and standard normal deviate generators perform satisfactorily. Furthermore, Kolmogorov-Smirnov tests show that the sampling distributions ofz, t, F, χ², andr generated by DATASIM simulations follow the appropriate theoretical distributions. Finally, estimates of Type I error rates obtained by DATASIM under various patterns of violations of assumptions are in close agreement with the results of previous analytical and empirical studies; These converging lines of evidence suggest that DATASIM may well prove to be a reliable and productive tool for conducting statistical simulation research.     

The dead donor rule: should we stretch it, bend it, or abandon it?

The dead donor rule--that persons must be dead before their organs are taken--is a central part of the moral framework underlying organ procurement. Efforts to increase the pool of transplantable organs have been forced either to redefine death (e.g., anencephaly) or take advantage of ambiguities in the current definition of death (e.g., the Pittsburgh protocol). Society's growing acceptance of circumstances in which health care professionals can hasten a patient's death also may weaken the symbolic importance of the dead donor rule. We consider the implications of these efforts to continually revise the line between life and death and ask whether it would be preferable to abandon the dead donor rule and rely entirely on informed consent as a safeguard against abuse.     

The effects of family composition,family health,parenting behavior and environmental stress on children's divorce adjustment

The traditional family composition model of children's divorce adjustment was compared to a family competence model. Subjects included 81 children whose parents remained married, were divorced, or were divorced and subsequently remarried. Divorced families had been separated for between 24 and 48 months. Custodial parents completed questionnaires regarding family functioning, occurrence of stressful life events, and child's psychosocial adjustment. Children completed questionnaires regarding parenting behaviors and self-esteem. A trained examiner conducted a structured diagnostic interview of the child. Multivariate analysis of covariance showed that family composition had a significant effect on the occurrence of stressful events and change in income but not children's adjustment. Hierarchical multiple regression correlations indicated the most powerful predictors of child adjustment were family competence variables which accounted for 21% of the variance in child adjustment scores. In contrast, family composition accounted for only 8% of variance in child adjustment scores. Further, hierarchical multiple regression correlations indicated that higher levels of family functioning were associated with families where parental hostility was low and parents displayed few rejecting behaviors while practicing consistent and appropriate discipline.     

Linguistic Phenomena and Language Selection in the REM Dreams of German-English Bilinguals

Sixteen German-English bilinguals were studied in a sleep laboratory for four nonconsecutive nights each. Half were native English speakers living in Zürich, and half native German speakers living in Atlanta. Presleep thought samples were solicited each evening and REM dream reports each night; subjects judged the waking appropriateness of their imagined speech and language phenomena, and also identified waking sources of their dream imagery, the following mornings. Incidences of dreaming and of speech therein generally were similar to those of monolinguals. Whether sessions were conducted in German (two nights) or English (two nights) did directly influence language selection in subjects' dreams. Judged appropriateness of language selection to imagined events was very high for thought samples, and high for REM dreams. Sources for thought samples were generally consonant with the language dominant at study site; for REM dreams this relationship was considerably weaker. Judged waking appropriateness to imagined situations was more strongly related to language selection than was the language reference of the supposed sources of those situations.     

Psychosocial predictors of stress associated with the male midlife transition

This study was designed to examine the correlates of developmental psychological stress for 36 middle-aged professional men. Based on sex role convergence and role adjustment theories, two sets of predictor variables were hierarchically entered into a multiple regression equation with a third set of variables entered to control for individual stressors. Controlling for individual stressors, midlife stress outcome was found to be influenced only by role adjustment (R²=.3593). The sex role convergence cluster did not account for a significant increase in variance. Controlling for individual stressors, the best univariate predictors of stress outcome associated with the midlife transition were (a) the quality of the parent-adolescent relationship and (b) marital satisfaction.     

Vulnerability to Stress: Self-Criticism and Stress-Induced Changes In Biochemistry

ABSTRACT It has been hypothesized that individuals who are high on the attribute of self-criticism are particularly vulnerable to failure stress. To test this hypothesis, we examined the relationship between self-criticism and changes in plasma homovanillic acid (HVA; the metabolite of dopamine) and emotion during exposure to an induced-failure task. Participants consisted of 21 women. Plasma HVA and emotion were assessed at three time points: baseline (T1), during stress exposure (T2), and 40 minutes after cessation of the stressor (T3). We found that self-criticism was significantly and positively related to changes in plasma HVA during stress exposure. In addition, the personality attribute was significantly and positively related to subjective ratings of stress and changes in scores on the Confusion-Bewilderment scale of the Profile of Mood States during the task. To our knowledge, this is the first study to report that self-criticism is related to stress-induced changes in biochemistry.     

EFFECTS OF REINFORCEMENT HISTORY AND INSTRUCTIONS ON THE PERSISTENCE OF STUDENT ENGAGEMENT

We examined the effects of three reinforcement histories on the persistence of task engagement by 2 fourth-grade students using a partially counterbalanced ABCDBCD design. In each condition, an experimenter made four student contacts during the first 2 min of each session (reinforcement baseline), followed by an 8-min extinction period. The reinforcement history that contained an instructional control component produced the greatest persistence in student engagement. The applied relevance of instructional control is discussed.     

Certification and Licensure Issues

Certification and licensure are important credentials for counselors. In less than 25 years, licensure laws on counseling have been passed in 41 states and the District of Columbia. Although much progress has been made regarding certification and licensure, all is not bliss. A reaction to certification and licensure issues is provided.