Outcomes of role stress: a multisample constructive replication.

Responses from four separate samples of accountants and hospital employees provided a constructive replication of the Bedeian and Armenakis (1981) model of the causal nexus between role stress and selected outcome variables. We investigated the relationship between both role ambiguity and role conflict--as specific forms of role stress--and job-related tension, job satisfaction, and propensity to leave, using LISREL IV, a technique capable of providing statistical data for a hypothesized population model, as well as for specific causal paths. Results, which support the Bedeian and Armenakis model, are discussed in light of previous research.     

Optimal solar-PV tilt angle and azimuth: An Ontario (Canada) case-study

The purpose of this article is to determine the tilt angle and azimuth for a photovoltaic panel in Ontario (Canada) at which revenue is maximised. Measured and modelled solar radiation data, simulated photovoltaic panel performance, hourly electricity market data and details regarding pricing regimes from 2003 to 2008 are used to study two different locations. In all instances, the desired tilt angle is slightly less than latitude (depending upon the particular pricing regime, between 36° and 38° for Ottawa, which is at a latitude of 45°N, and between 32° and 35° for Toronto, which is at a latitude of 44°N), and the desired azimuth is close to due south (depending upon the particular pricing regime, between 4° west of due south and 6° east of due south for Ottawa, and between 1° west of due south and 2° east of due south for Toronto). In conclusion, the importance of solar electricity – particularly valuable because of when it is produced and where it can be produced – is highlighted, as are future priorities for research.     

Correction for variance restriction in point-biserial correlations.

A correction procedure is proposed for adjusting point-biserial correlations for attenuation produced by inopportune splits in the dichotomous variable. The correction procedure permits estimation of the point-biserial correlation that would have been seen had equal proportions been present. Monte Carlo simulation evidence is provided for the accuracy of the correction procedure. Also, an example is provided from the employee turnover literature to illustrate how the correction procedure may be used. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Meta-analysis and moderator variables: A cautionary note on transportability.

Despite the recent popularity of meta-analysis as a tool for summarizing empirical results across a number of studies, surprisingly little research has been conducted on the accuracy of these procedures under a variety of population conditions. Of concern in this study was the 90% credibility value (K. Pearlman et al, see record 1980-31533-001) advocated as a rule of thumb regarding the transportability of employment test validities. We investigated the ability of this meta-analytic rule to detect the presence of discretely defined moderator variables, that is, the ability of the rule to detect instances where transportability is inappropriate. An infinite sample size analysis and a mathematical proof demonstrated that the transportability rule may produce erroneous inferences at rates higher than expected. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The power of the Schmidt and Hunter Additive Model of Validity Generalization.

Monte Carlo simulation and infinite sample-size analysis were used to test inferences based on the Schmidt and Hunter Additive Model of Validity Generalization when rho in some instances was zero. Results of both large (n?=?1,000) and small (N?     

Failure to detect moderating effects: Is multicollinearity the problem?

We show that Morris, Sherman, and Mansfield's (1986) contention that multicollinearity causes ordinary least squares–moderated multiple regression (OLS–MMR) to underestimate the importance of moderator effects is incorrect for their own data. Multicollinearity was reduced to the point that it was negligible by transforming predictor variables and moderator variables to standard scores prior to computing cross-product terms. We show the resulting cross-product terms both mathematically and empirically to have near-zero correlations with standardized predictors and moderators. Yet, as Arnold and Evans (1979) showed, the results of OLS–MMR are unchanged by this linear transformation of scale. Morris et al's (1986) finding of significant moderator effects when using principal-components regression (PCR) is probably a result of some artifact of PCR. (PsycINFO Database Record (c) 2010 APA, all rights reserved)