Moderated regression analysis and Likert scales: too coarse for comfort.

One of the most commonly accepted models of relationships among three variables in applied industrial and organizational psychology is the simple moderator effect. However, many authors have expressed concern over the general lack of empirical support for interaction effects reported in the literature. We demonstrate in the current sample that use of a continuous, dependent-response scale instead of a discrete, Likert-type scale, causes moderated regression analysis effect sizes to increase an average of 93%. We suggest that use of relatively coarse Likert scales to measure fine dependent responses causes information loss that, although varying widely across subjects, greatly reduces the probability of detecting true interaction effects. Specific recommendations for alternate research strategies are made.     

Prejudice Against a Progay Man in an Everyday Situation: A Scenario Study1

A scenario study was performed to investigate whether people in the street would be less likely to respond positively to a stranger's request for a small favor if the stranger wore a T-shirt bearing a progay slogan. One hundred and eighteen female and 112 male participants were each presented with six scenarios, all of which asked them to imagine being approached by a person requesting change for a banknote. The dependent variable in the study was the participant's judgment, on a 7-point scale, of how likely he or she would be to help. Five of the scenarios were included as distractors. In the critical scenario, the requester was described as wearing a plain T-shirt or one with either a progay or a control slogan printed on it. The male participants in the progay condition showed a significantly lower level of help than those in either of the control groups. The antigay pattern, however, was not obtained in the responses of the female participants. The results are discussed with reference to other findings in the literature, and their implications for people's responses to progay persons in everyday life are considered.     

Stimulus recognition and the mere exposure effect.

A meta-analysis of research on Zajonc's (1968) mere exposure effect indicated that stimuli perceived without awareness produce substantially larger exposure effects than do stimuli that are consciously perceived (Bornstein, 1989a). However, this finding has not been tested directly in the laboratory. Two experiments were conducted comparing the magnitude of the exposure effect produced by 5-ms (i.e., subliminal) stimuli and stimuli presented for longer durations (i.e., 500 ms). In both experiments, 5-ms stimuli produced significantly larger mere exposure effects than did 500-ms stimuli. These results were obtained for polygon (Experiment 1), Welsh figure (Experiment 2), and photograph stimuli (Experiments 1 and 2). Implications of these findings for theoretical models of the mere exposure effect are discussed.     

An assessment of the Edwards Personal Preference Schedule from the perspective of the five-factor model.

We examined the validity of need scales of the Edwards Personal Preference Schedule (EPPS) by correlating them with a measure of the five basic factors of personality; we also considered test format as a possible source of invalidity. Three hundred thirty (223 women, 107 men) undergraduate students completed both the NEO Personality Inventory (NEO-PI)--a measure of the five factors--and one of two versions of the EPPS. Results show that both ipsative and normative versions of the EPPS could be meaningfully interpreted within the five-factor model, although the ipsative, forced-choice format of the standard EPPS apparently lowered validity coefficients and decreased convergent and discriminant validity. We argue that the five-factor model can provide a useful interpretive context for evaluating many clinical measures.     

Choice of medical specialty: analysis of students' needs.

The purposes of this study were to assess the career development needs of entering medical students as measured by the Medical Career Development Inventory and to examine gender differences in responses to the inventory. A total of 115 entering medical students (representing two entering classes) took the inventory two months prior to matriculation. Analysis suggested that this sample of entering students had formed a vocational identity and that they had evaluated the suitability and viability of a commitment to a physician's career. However, the participants had not formed a clear picture of their specialty interest and goals. No significant gender differences were indicated. A recommended career assistance workshop is presented as appropriate for these students' needs.     

Validity and clinical scale comparisons between the MMPI and MMPI-2 with psychiatric inpatients.

This study was designed to investigate the comparability of the original MMPI (1950) and the MMPI-2 (1989) with a psychiatric patient population. 34 male and 3 female patients, shortly after admission to one of two acute psychiatry units, completed the old and revised versions of the MMPI. Paired t tests indicated but scant differences for raw scores, while many more differences were found among T scores for validity, clinical, and supplemental scales. Analyses, however, showed all scales on the two forms to be highly correlated. Analysis of the high-point and two-point codes across the two administrations also showed relative stability, although the proportion of Scales 2 (Depression) and 8 (Schizophrenia) decreased, while those for Scales 6 (Paranoia) and 7 (Psychasthenia) increased markedly in the MMPI-2 protocols. Examination of each version's discriminability among mood- and thought-disordered subsamples suggested that the MMPI provides slightly better delineation between diagnostic classes. Discriminant function analyses showed that there were essentially no differences between the two forms in the accurate classification of clinical and nonclinical groups. The findings reported here provide support for the MMPI-2; despite modification, the newer form retains the advantages of the original MMPI. Differences found here may be unique to psychiatric patients and their patterns of MMPI/MMPI-2 equivalence and may not generalize to other special populations.     

Human evaluative conditioning: acquisition trials, presentation schedule, evaluative style and contingency awareness.

Two different processes may be operative in human Pavlovian conditioning: signal learning and evaluative learning. Whereas most studies on evaluative conditioning focused on a mere demonstration of the phenomenon or on a theoretical analysis of the underlying processes, some basic parameters of evaluative learning are still unexplored. Hence, using the standard neutral picture--(dis)liked picture pairing paradigm (Baeyens, Eelen & Van den Bergh, 1990), in this study the effect of two parameters of evaluative conditioning was assessed on a between-subjects base, namely the Number of Acquisition Trials (2/5/10/20) and the Presentation Schedule of the stimulus pairs (blockwise or random). Additionally, the study included an exploratory analysis of the potential effects of the Evaluative Style of subjects (Feelers vs Thinkers, operationalized in terms of speed of emitting evaluations). Finally, the relationship between contingency awareness and evaluative learning was reassessed. Neutral-liked conditioning was found to be quadratically related to the number of acquisition trials (increase in effect up to 10 trials, decrease from 10 to 20 trials), whereas neutral-disliked conditioning linearly increased with increasing numbers of trials. Randomized vs blockwise presentation schedules of the stimulus pairs did differentially affect the overall pattern of conditioning, but in a way which was both unexpected and difficult to account for theoretically. Both the Evaluative Style of subjects and contingency awareness were demonstrated to be generally orthogonal to conditioned shifts in CS valence. Based on these findings, some practical suggestions are provided for the application of evaluating conditioning based therapeutical interventions to affective-behavioral disorders which are centred around inappropriate (dis)likes.     

Psychological factors in abortion. A review.

Psychological research is increasingly involved in debates regarding abortion. While recognizing the diversity of ethical and moral issues intertwined with abortion, the American Psychological Association (APA) has focused its involvement on psychological factors, most recently by appointing an expert panel to review the literature on psychological effects. This article notes the history of APA involvement and reports on the panel's conclusions. It presents evidence that abortion is not likely to be followed by severe psychological responses and that psychological aspects can best be understood within a framework of normal stress and coping rather than a model of psychopathology. Correlates of more negative responses following abortion are also discussed.     

Orientation congruency effects in visual search.

Subjects searched for the letter E in a background of Ls and Fs in displays that had 1, 2, 4, 8, or 12 letters. The letters could be shown at one of six orientations (upright or rotated clockwise in 60 degrees increments). The displays were either congruent for orientation (all letters had the same orientation) or incongruent (letters in haphazard orientations except for the target on E-present trials). Search time increased linearly with the number of letters in the display, and more so for E-absent trials than for E-present trials. Letter orientation, in general, increased search time and produced an M-shaped function. Furthermore, orientation effects were attenuated in congruent displays relative to those produced by incongruent displays. The results demonstrated systematic orientation effects on the time to search for a simple pattern embedded in simple backgrounds, and provided converging evidence for the orientation-congruency effect found by Jolicoeur (1990b, Journal of Experimental Psychology: Human Perception and Performance, 16, 351-364).