Personality Trait Change in Adulthood

1. Personality Trait Change in Adulthood Brent W. Roberts Daniel Mroczek

2. FULL DISCLOSURE

3. Review • Focus • Average change over a sample or population • Individual differences in the rate of change

4. Cross-sectional Studies • Reviews Srivastava et al. (2003) • Large internet-based study (N = 132,515) • Results • Size and direction of differences consistent with previous findings, but interpreted as change • Roberts and Mroczek’s claim that “60-year-old participants scored higher than 40-year old participants on most dimensions…” (no basis for this claim!)

5. Longitudinal Studies • Reviews 2006 Roberts et al. paper • 92 longitudinal studies covering ages 10-101 • Found significant change in 75% of traits in middle (40-60) and old (60+) age • Figures (Figure 2 from meta-analysis) • Standardized measure of mean differences • How much of a standard deviation • Costa and McCrae (2006) noted that these are the same modest changes they had been reporting for some time

7. Individual Differences in Change • Two levels of change • Mean levels of change • Individual differences in change • Do some individuals change faster? • Do some individuals change in a different direction? • Multiple ways to assess • RCI • Growth models

9. Individual Differences in Change • Used to illuminate why people change or what change is related to • People who experience satisfying careers show greater declines in N and increases in C • Long-term increases in N are related to mortality (Mroczek & Spiro, 2007) • Increases in Ho are related to mortality (Siegler et al., 2003)

11. Personality Plasticity After Age 30 Antonio Terracciano Paul T. Costa, Jr. Robert R. McCrae

12. Main Study Question • Longitudinal data suggest that • Personality is relatively stable • Stability is greater in adulthood than in prior years • When, if at all, does rank order stability plateau?

13. Differential Predictions

14. Methods • Baltimore Longitudinal Study of Aging • Large sample for part of a multidisciplinary study • Recurring assessment • Measures • GZTS • NEO and NEO-PI-R • California Adult Q-Set

15. Rank Order Stability Results • Across domains • NEO: rank order stability did not differ between age groups • GZTS: rank order stability did not differ between age groups • At scale level • Extraversion domain showed more stability in 50-65 than > 65 group • Not replicated in similar GZTS scales

16. Personality Trait Development From Age 12 to Age 18: Longitudinal,Cross-Sectional, and Cross-Cultural Analyses Robert R. McCrae and others

17. Purpose • To assess mean-level personality change in adolescence • Also… • Compare longitudinal results to cross-sectional data from the U.S. • Examine factor invariance • Rank-order stability

18. Methods • Participants • 521 boys and 249 girls • Scored above 97th percentile in academic ability • 230 students were assessed four years later • Instrument • NEO-FFI • Short version of the NEO-PI-R

19. Factor Invariance • Compared structure of first and second ratings • CFA simple structure model • CFI suggested poor fit • RMSEA suggested good fit • Constraining factor loadings to be identical across intervals caused decreases in fit, but no change in CFI or RMSEA • Procrustes rotation • Coefficients for N, E, and C greater than .90 • Coefficients for O and A greater than .85

20. Retest Reliabilities • Considerably lower than in older samples • Boys • Range: .31 for A to .49 for C • Median: .39 • Girls • Range: .30 for N to .63 for C • Median: .34

21. Mean Level Differences • MANOVA • DVs: Five NEO-FFI domain T-scores • IVs: Gender, Time • Interaction: Gender × Time • Results • No main effects of Time for N, E, or A • O increased and C decreased • Gender × Time effect on N

22. Differences for boys

23. Differences for girls