Robust nonorthogonal analyses revisited: An update based on trimmed means

Three approaches to the analysis of main and interaction effect hypotheses in nonorthogonal designs were compared in a 2×2 design for data that was neither normal in form nor equal in variance. The approaches involved either least squares or robust estimators of central tendency and variability and/or a test statistic that either pools or does not pool sources of variance. Specifically, we compared the ANOVA F test which used trimmed means and Winsorized variances, the Welch-James test with the usual least squares estimators for central tendency and variability and the Welch-James test using trimmed means and Winsorized variances. As hypothesized, we found that the latter approach provided excellent Type I error control, whereas the former two did not.Financial support for this research was provided by grants to the first author from the National Sciences and Engineering Research Council of Canada (#OGP0015855) and the Social Sciences and Humanities Research Council (#410-95-0006). The authors would like to express their appreciation to the Associate Editor as well as the reviewers who provided valuable comments on an earlier version of this paper.     

Evaluating sex discrimination claims: the mediating role of attributions.

The role of attributions in judgments of sex discrimination was examined in 2 laboratory experiments. In Study 1, participants read 1 of 12 brief scenarios in which limited information about the strength of evidence against a fictitious corporation and occupational gender stereotype were manipulated. Results suggested that attributions mediated the relationships between participants' gender, strength of evidence, and discrimination judgments. In Study 2, participants were provided with 1 of 3 detailed, typewritten summaries of evidence presented in a sex discrimination trial. Results indicated that jurors' gender was again significantly related to attributions and to sex discrimination judgments even in the face of substantial objective information related to the case. The variance in observers' judgments associated with gender, however, appeared to be greatest when information about the organization's guilt or innocence was equivocal.     

Using Skills Gained Through Volunteerism in Job Searches: A Workable Strategy

A number of recent theoretical and empirical articles have examined various aspects of volunteerism. Research which has established the increasing importance of career development as a primary goal of many volunteers has largely been concerned with individuals already established in their careers. This article extends current research by focusing on recent or soon-to-be college graduates. It integrates career-development volunteerism research with recent work from the job search literature. The paper includes specific suggestions for obtaining volunteer experience which targets employer-identified desirable job skills.     

Job context, selection decision outcome, and the perceived fairness of selection tests: biodata as an illustrative case

S. W. Gilliland (1993) has proposed a model of perceived selection system fairness to help understand applicants' prehire and posthire behavior. The present study aimed to verify and extend his framework by investigating the role of job context in the formation of fairness perceptions of biodata. A sample of 255 students (108 men, 147 women) completed an operational biodata instrument, believing that it would be used to hire persons for either international, local, or unspecified entry-level managerial positions. Participants were then presented with outcome information (selected or rejected for further consideration). Consistent support was found for the research hypotheses derived from the Gilliland model. Participants' perceptions of the fairness and job relatedness of biodata were affected by the selection context and decision outcome. The importance of considering selection context in assessments of perceived test fairness is discussed.     

Adolescents' self-efficacy to communicate about sex: its role in condom attitudes, commitment, and use

This study examined whether and how self-efficacy to communicate with parents and peers about sex relate to sexually experienced adolescent males' and females' (N= 144, 112) condom attitudes, intentions, and use. Results showed that males who reported greater self-efficacy to communicate with parents used condoms more frequently; and both males and females who can communicate with peers used condoms more frequently. Self-efficacy to communicate with peers was related to more positive condom attitudes, which in turn were associated with greater condom commitment and use. Greater ability to communicate with parents was also related to greater condom commitment and use among males. These results suggest the importance of designing interventions that give adolescents the skills they need to feel efficacious in their ability to communicate about sex and contraception.     

Self-reported comfort in athletic training to same- and opposite-sex athletes

To assess the comfort of athletic trainers in providing care to athletes of the same- and opposite-sex, the Gender Comfort in Athletic Training Questionnaire was developed. Cronbach alpha was .72. The 8-item questionnaire was mailed to 235 participants, who were senior athletic training students and clinical instructors affiliated with 14 university athletic training programs. 192 questionnaires were returned (82%). Only one t test showed a significant mean difference in reported comfort between women (n= 103, M=2.8, SD= 0.8; disagree) and men (n= 89, M=3.1, SD=0.8; neutral) on the statement: I feel more comfortable providing athletic training services to male athletes than female athletes. The women and men in this sample were similar in their self-ratings of comfort in providing athletic training services to male and female athletes.     

Variations in the relationship between radius of curvature and velocity as a function of joint motion

A power law describes the relationship between the geometric properties of a trajectory (radius of curvature) and movement kinematics (tangential velocity) in curved drawing movements. Although the power law is a general law of motion, there are conditions under which it degrades. In particular, the power law may be less explanatory of movements around certain joints. The present study considered how varying motion around different joints influenced the fit of the power law. Motions associated with finger and wrist, or elicited by an isometric force production task, were compared. The power law was most explanatory of finger motion and isometric production and least explanatory of wrist motion. The fit of the power law for finger and wrist motion suggested separate laws for each joint system. Since the fit of the power law was better for finger than for wrist motion, there is some suggestion that the power law better explains motion around fewer or simpler joint systems.     

Psychophysiological mediators of caregiver stress and differential cognitive decline

The authors examined relationships between chronic stress and cognitive decline and whether such relationships were mediated by psychophysiological factors. Ninety-six caregivers of spouses with Alzheimer's disease (AD) were compared with 95 similar noncaregiver spouses. All were free of diabetes. Although the groups started similarly, over 2 years caregivers declined by a small but significant amount (1 raw score point and 4 percentile points, each p<.05) on Shipley Vocabulary. In contrast, noncaregivers did not change. Higher hostile attribution (beta=-.09; p<.05) and metabolic risk (beta=-.10; p<.05) in caregivers mediated the cognitive decline. This is the first study of cognitive decline and mediators in caregivers. This work has implications for caregiver and care-recipient health and for research on cognition, psychophysiology, diabetes, and AD.     

Convergence of biological and psychological perspectives on cognitive coordination in schizophrenia

The concept of locally specialized functions dominates research on higher brain function and its disorders. Locally specialized functions must be complemented by processes that coordinate those functions, however, and impairment of coordinating processes may be central to some psychotic conditions. Evidence for processes that coordinate activity is provided by neurobiological and psychological studies of contextual disambiguation and dynamic grouping. Mechanisms by which this important class of cognitive functions could be achieved include those long-range connections within and between cortical regions that activate synaptic channels via NMDA-receptors, and which control gain through their voltage-dependent mode of operation. An impairment of these mechanisms is central to PCP-psychosis, and the cognitive capabilities that they could provide are impaired in some forms of schizophrenia. We conclude that impaired cognitive coordination due to reduced ion flow through NMDA-channels is involved in schizophrenia, and we suggest that it may also be involved in other disorders. This perspective suggests several ways in which further research could enhance our understanding of cognitive coordination, its neural basis, and its relevance to psychopathology.