Personality for free: psychometric properties of a public domain Australian measure of the five-factor model

Fifty items from Goldberg's International Personality Item Pool were compiled to form a public-domain measure of personality, the Australian Personality Inventory (API). Data from a random community sample (N=7615) and a university-based sample (N =271) were used to explore psychometric properties of this 50-item measure of the five-factor model of personality (FFM). In both samples, internal reliabilities were adequate. In the university-based sample an appropriate pattern of convergent and divergent relationship was found between scale scores and domain scores from the NEO Five-Factor Inventory. After adjusting for an apparent response set (mean response across items), exploratory factor analyses clearly retrieved the FFM in both samples. It is provisionally concluded that raw scale scores from the API provide reliable estimates of the FFM, but adjustment for mean response across the 50 items might clarify the five-factor structure, especially in less educated samples