Predicting Life Outcomes with Individual Differences in Personality and Cognitive Ability: A Longitudinal Heritability Study
Year: 2024
Type: dissertation
Study design: Observational Study
Abstract: Numerous studies have examined personality and cognitive ability in relation to life outcomes. However, longitudinal studies examining these relationships are relatively scarce, leaving the extent to which individual differences can account for life outcomes still unclear. The focus of this study was to use the latest European twin data to study personality and cognitive ability as predictors for the life outcomes: education level, occupation, life satisfaction and friendship. Heritability analyses of the variables were performed to provide supporting context to individual differences. A sample of 842 young adults (mean age 23 at Wave 1) using data from the TwinLife project was analysed through a longitudinal within-person correlation analysis with a four-year period between Wave 1 and Wave 2. Heritability was calculated via Falconer’s formula using data from monozygotic and dizygotic twin pairs. The results show that cognitive ability was the overall best predictor with robust correlations to education level (r = .34) and occupational outcomes (r = .31). Conscientiousness was the strongest predictor out of the personality traits and was associated to life satisfaction (r = .22), education (r = .10) and occupation (r = .11). The heritability of all predictor variables, specifically cognitive ability (h2 = .88) and extraversion (h2 = .89), was high and should be considered when interpreting the results. Limitations regarding reliability of scales and attenuation likely yielded conservative estimates on life outcomes overall. Recommendations for future research is studying the heritability with more comprehensive methods, especially the genetic variance of the correlations themselves. Keywords: personality, cognitive ability, life outcomes, heritability
Author: Paulander, Filip
Language: English
Subfield: Experimental and Cognitive Psychology
Field: Psychology
Domain: Social Sciences
Open Access status: green
OpenAlex ID: W7005144464