Profile similarity or agreement is increasingly used in personality research and clinical practice and has potential applications in many other fields of psychology. I compared 4 measures of profile agreement-the Pearson r, Cattell's (1949) r p , McCrae's (1993) r pa , and an intraclass correlation coefficient (double entry), ICC DE -using both broad factor and specific facet profiles. Matched versus mismatched self-ratings/other ratings on the NEO Personality Inventory-3 were used as criteria. At the factor level, r pa and ICC DE were comparable, and both were superior to r p in distinguishing matched versus mismatched profiles. At the facet level, ICC DE was superior to the other coefficients. The Pearson r performed better than expected.Measures of profile agreement quantify the extent to which two profiles match across a range of characteristics. The profiles to be compared might be a set of ability measures administered to one individual on two occasions or ratings from two observers on the personality traits of a single target. Measures of agreement are useful in clinical applications in which they can help to evaluate the accuracy of data about an individual (see Costa & Piedmont, 2003), and they have been used to validate aggregate personality profiles of cultures (McCrae, Terracciano, & 79 Members of the Personality Profiles of Cultures Project, 2005) and assess the accuracy of national character stereotypes . Profile agreement between individual scores and fixed prototypes has been proposed as a guide to personality disorder diagnosis (e.g., Lynam & Widiger, 2001) and might have applicability in employee selection. For all these reasons, it would be useful to identify the most effective measure of profile agreement.A good index of profile agreement would show high values when the two profiles were in fact similar. However, there are several ways to conceive of agreement between profiles, and it is not clear which of these is optimal. To circumvent this problem, I evaluated several indexes using self-reports and observer ratings of personality traits under the assumption that true similarity will be higher when the target for the two profiles is the same individual rather than two randomly paired individuals. Correlations with this matched/mismatched criterion can be used to evaluate the different indexes. Note that this criterion does not prejudge the form of agreement. Either absolute closeness of scores or similarity of profiles shapes might be most effective in distinguishing matched from mismatched profiles, and different indexes place different emphases on these components. The data I examined here -3 (NEO-PI-3;, but it seems likely that the results would be generalizable to other instruments.
HHS Public AccessThe most obvious candidate for agreement is the Pearson correlation, but it is generally dismissed on the grounds that it is insensitive to differences in profile elevation (Cattell, 1949;Terracciano & McCrae, 2006): Two profiles may have the same shape and thus a high correlat...