Person-Fit to the Five Factor Model of Personality

The Five Factor Model (FFM), a valid model of interindividual differences in the personality of a group of people, reportedly does not always provide a good fit for the individuals of that group. In addition to intraindividual variation across a considerable period of time, meaningful intraindividual variation can be observed within a single test administration. Two person-fit indices showed that the FFM is an adequate model for 95% of the 1,765 target-judge pairs in four different countries (Belgium, the Czech Republic, Estonia, and Germany): the double-entry intraclass correlation (ICCDE), which indicated that the 30 NEo PI-R scores on scales measuring the same personality trait are more similar and certainly less different than scores measuring different traits, and the individual contribution to the extracted eigenvalues (Z(eig)). The individual response pattern to the personality questionnaire characterized by the ICCDE and Z(eig) strongly determined the percentage of explained variance for the group-level factor structure of interindividual differences and the mean self-observer profile agreement. We demonstrate that, if the percentage of variance explained by the first five principal components is high enough, the FFM also provides an adequate fit at the individual level for most people.