The Five-factor Model of Personality

One of the major catalysts for the advancement of research on personality in recent years has been the growing consensus for a personality model encompassing five broad dimensions, namely Neuroticism (N), Extraversion (E), Openness to Experience (O), Agreeableness (A), and Conscientiousness (C). These broad factors subsume most personality traits and are known as the Big Five or Five-Factor Model (FFM; Digman, 1990; McCrae & John, 1992). The FFM did not originate from a particular personality theory or clinical experience; instead, the FFM emerged as an empirical model from two independent research traditions. The first was the lexical analysis of personality terms that occur in natural languages. The underlying principle of the lexical approach is that the most important traits necessary to describe individual differences become encoded in natural languages. The second approach was the factor analysis of different theorybased personality inventories, which converged on the same five factors (Markon et al., 2005). Systematic research on the FFM has revealed a number of important features of personality traits. First, studies using the Revised NEO Personality Inventory (NEOPI-R; Costa & McCrae, 1992), and other measures have established that all five factors have strong genetic bases, with heritability estimates from twin studies indicating that about 50% of the variance in personality traits is accounted for by additive and non-additive genetic factors (Jang et al., 1998; Bouchard & Loehlin, 2001). Second, given their genetic roots, it might not be surprising that personality traits are enduring dispositions, with a large body of literature showing high rank-order stability (r ~ .75) in adulthood (Roberts & Del Vecchio, 2000), even after decades (Terracciano et al., 2006a). Third, although individual differences are substantially stable, personality traits show modest maturational changes, which can be briefly summarized by noting that most people tend to decline in N, E, and O, and to increase in