Knowledge that Transforms

This research presents the inferential statistics for Cronbach's coefficient alpha on the basis of the standard statistical assumption of multivariate normality. The estimation of alpha's standard error (ASE) and confidence intervals are described, and the authors analytically and empirically investigate the effects of the components of these equations. The authors then demonstrate the superiority of this estimate compared with previous derivations of ASE in a separate Monte Carlo simulation. The authors also present a sampling error and test statistic for a test of independent sample alphas. They conclude with a recommendation that all alpha coefficients be reported in conjunction with standard error or confidence interval estimates and offer SAS and SPSS programming codes for easy implementation.

In testing for the self-serving bias in performance evaluation, the authors propose that comparing managers' counterfactual and prefactual thoughts about subordinates' performance is more conclusive than the attributional approach and also offers practical advantages. In a study with 120 managers, a 4-way interaction of subordinate performance, temporal perspective, direction, and reference confirmed the predicted pattern. Managers' thoughts about how a weak performance could have been enhanced had external references, but thoughts about how such a performance could be enhanced in the future focused on the leader. This asymmetry was only observed for weak performance. Results are discussed with regard to biases in leaders' performance evaluations and to how counter- and prefactual thoughts could be used for leadership research and practice.

Methodological problems in studies of union commitment were identified and illustrated with data from 4,641 members and 479 stewards in 297 local teachers' unions. Using a 20-item union commitment scale, results confirmed the existence of 3 substantive factors and 1 method factor at the individual level of analysis: loyalty to the union, responsibility to the union, willingness to work for the union, and a factor of negatively worded items. Tests of measurement invariance showed that the scale captured commitment for rank-and-file members but not for union stewards. The authors also found partial measurement invariance between long-time and newer members and full measurement invariance between men and women. Finally, the authors found that violation of the statistical assumption of independence reduced model fit when individual commitment scores were analyzed without attention to the hierarchical nature of the data.

Work flow policies are shown to induce a change in average between-workers variability (worker heterogeneity) and within-worker variability in performance times. In a laboratory experiment, the authors measured the levels of worker heterogeneity and within-worker variability under an individual performance condition, a work sharing condition, and a fixed assignment condition. The work sharing policy increased the levels of worker heterogeneity and worker variability, whereas the fixed assignment policy decreased them. These effects, along with work flow policy main effects on mean performance times and variability are examined. This article represents an initial step in understanding effects that may be important in the selection of an operating policy, the ignorance of which may lead to costly misestimates of performance.

Two experiments (N = 147 and N = 90) explored the use of multiple independent lineups to identify a target seen live. In Experiment 1, simultaneous face, body, and sequential voice lineups were used. In Experiment 2, sequential face, body, voice, and clothing lineups were used. Both studies demonstrated that multiple identifications (by the same witness) from independent lineups of different features are highly diagnostic of suspect guilt (G. L. Wells & R. C. L. Lindsay, 1980). The number of suspect and foil selections from multiple independent lineups provides a powerful method of calibrating the accuracy of eyewitness identification. Implications for use of current methods are discussed.

Three studies demonstrated that interactional justice was able to attenuate egocentric bias, i.e., the tendency to regard a larger share for oneself as fair. Study 1, an experimental study of negotiation, showed that fair interpersonal treatment led to a smaller egocentric bias, quicker settlements, and fewer stalemates. Study 2 showed that fair treatment was related to a smaller egocentric bias in a real-life context. University students were more willing to accept a higher tuition fee and less willing to cut the salary of their teachers if the interpersonal treatment received from the teachers was more positive. Study 3 showed experimentally that in support of fairness heuristic theory, when the fair interpersonal treatment received could be attributed externally, its attenuating effect on the egocentric bias disappeared.

The purpose of this study was (a) to provide additional tests of C. E. Lance, Newbolt, et al.'s (2000) situational specificity (vs. method bias) interpretation of exercise effects on assessment center postexercise dimension ratings and (b) to provide competitive tests of salient dimension versus general impression models of assessor within-exercise evaluations of candidate performance. Results strongly support the situational specificity hypothesis and the general impression model of assessor cognitive processes in which assessors first form overall evaluations of candidate performance that then drive more specific dimensional ratings.

Theories provide meaning. They allow us to understand and interpret data. Theories specify which variables are important and for what reasons, describe and explain the relationships that link the variables, and identify the boundary conditions under which variables should or should not be related (Campbell, 1990). Theories help identify and define problems, prescribe a means for evaluating or solving the problems, and facilitate responses to new problems. They permit generalization beyond the immediate sample and provide a basis for making predictions. Theory tells us why something occurs, not simply what occurs. Research in the absence of theory is often trivial—a technical feat more likely to yield confusion and boredom than insight. In contrast, research that is guided by theory, or that develops theory, generates understanding and excitement. To signal the commitment of the Journal of Applied Psychology not only to the publication of theory-driven and theory-building research but also to the publication of theory per se, in September 2002 the journal issued a call for papers that present new theoretical models and conceptual analyses. We urged authors to submit conceptual manuscripts that extend beyond the current literature— that offer more than a review of the existing literature and more than a repackaging of established constructs and models. We emphasized that manuscripts should offer new theoretical insights and propose new explanations of constructs, relationships, and/or

From the standpoint of test validation, veterinary medicine provides both a unique context in which to study the validity of Graduate Record Examinations (GRE) test scores and a singular opportunity to address the shortcomings typical of many GRE validity studies. This article documents a study of the validity of the GRE General Test for predicting 1st-year grade averages in a comprehensive sample of veterinary medical colleges. For each of 16 veterinary medical colleges, statistical corrections were applied to correct for the effects of range restriction in the predictors and unreliability of the criterion. When fully corrected for both range restriction and unreliability, the resulting validity coefficients were, on average,.53 for the combination of all 3 GRE General Test scores,.59 for undergraduate grade point average, and.71 for GRE scores and undergraduate grade point average together.

In a preliminary attempt to determine the generalizability of data from laboratory mock-crime studies, the authors examined the similarities and differences among the cardiovascular, electrodermal, and respiration responses of deceptive and nondeceptive individuals elicited to crime-relevant and crime-irrelevant questions. Participants in the laboratory group were randomly assigned to nondeceptive (n = 28) or deceptive (n = 27) treatment groups, and a mock-crime scenario was used. The field participants were confirmed nondeceptive (n = 28) or deceptive (n = 39) criminal suspects who underwent polygraph examinations between 1993 and 1997. The results indicated that there were salient differences between field and similarly obtained laboratory polygraph response measures. However, accuracy of laboratory participants' classifications using logistic regression analysis was not significantly different from field participants' classification accuracy.