title: A Meta-Analysis of the Reliability of Free and For-Pay Big Five Scales.
abstract: The present study meta-analytically compared coefficient alpha reliabilities reported for free and for-pay Big Five scales. We collected 288 studies from five previous meta-analyses of Big Five traits and harvested 1,317 alphas from these studies. We found that free and for-pay scales measuring Big Five traits possessed comparable reliabilities. However, after we controlled for the numbers of items in the scales with the Spearman-Brown formula, we found that free scales possessed significantly higher alpha coefficients than for-pay scales for each of the Big Five traits. Thus, the study offers initial evidence that Big Five scales that are free more efficiently measure these traits for research purposes than do for-pay scales.
authors.affiliation: a The University of Texas at Arlington.
authors.forename: Tyler
authors.initials: T
authors.lastname: Hamby
authors.affiliation: a The University of Texas at Arlington.
authors.forename: Wyn
authors.initials: W
authors.lastname: Taylor
authors.affiliation: a The University of Texas at Arlington.
authors.forename: Audrey K
authors.initials: AK
authors.lastname: Snowden
authors.affiliation: b The University of Texas at Austin.
authors.forename: Robert A
authors.initials: RA
authors.lastname: Peterson
mesh_terms: D006801:Humans; D010552:Personality Assessment; D011594:Psychometrics; D015203:Reproducibility of Results
keywords: Big Five; assessment; for-pay scales; free scales; meta-analysis