1. All in the Family
The Shared and Distinctive Causes of Personality and Well-Being
Chris C. Martin & Corey L. M. Keyes | Department of Sociology, Emory University, Atlanta, GA
Introduction
Methods
Results
Sample
‣ The twin sample examined here included a total of 1,386 twins from same- sex twin pairs: 186 female monozygotic (MZ), 198 female dizygotic (DZ), 163 male MZ, and 123 male DZ twins. Their mean age was 44.6 (SD = 12.2).
‣ Emotional, psychological and social well-being were measured using Likert scales. The Midlife in the United States (MIDUS) adjectival scale was used to measure the Big Five.
Analytic Plan
‣ We used structural equation models to determine the genetic and environmental sources of personality traits and well- being levels. The phenotypic variance comprises additive genetic effects (A), shared environmental effects (C), and unique environmental effects (E) (Kendler & Prescott, 2006).
An Exaggerated Claim
‣ Personality traits exhibit a very strong association with subjective well-being (SWB). Genes may partially underlie this phenomenon (Diener, Suh, Lucas, & Smith, 1999, p. 282).
‣ The literature on the genetic variance in well-being, however, has solely focused on emotional well-being (e.g., Bartels & Boomsma, 2009).
‣ Thus, some claims may be exaggerated. For instance, Weiss, Bates, and Luciano (2008) found no genetic variance in SWB to be unique from personality, and claimed that "happiness is a personality thing." However, they neglected psychological and social well-being.
Using the Tripartite Model
‣ The tripartite models derives from the hedonic and eudaimonic traditions of well-being scholarship.
‣ The eudaimonic tradition includes psychological well-being, which focuses on functioning in domains such as purpose, contribution, and mastery in life.
‣ The eudaimonic tradition also includes social well-being, which focuses on functioning in domains such as social acceptance, societal integration, and social contribution.
Bivariate Model
‣ In this case and the two cases below, the best fitting model included additive genetic effects and individual-specific environment , and excluded shared environmental effects.
‣ The genetic correlations with SWB ranged from a low of .42 for Agreeableness (Openness = .50, Neuroticism = -.53, and Conscientiousness = .55) to a high of .62 for Extraversion. The unique environmental correlations with SWB ranged from a low of .40 for Openness (Conscientiousness = .45, Agreeableness = .46, and Extraversion = .51) to a high of -.58 with Neuroticism.
Model run separately for each trait.
Six-Variable Cholesky Decomposition Model
‣ This model decomposes the genetic and environmental contribution to SWB into those shared with the Big Five versus those unique to SWB.
‣ For genetic effects, the total heritability of SWB was 72%. Of this total, 64% was shared with personality and 36% was unique. Individual-specific environmental effects account for 28% of the variance in SWB, of which 63% was shared with personality measures and 37% was unique.
References
Bartels, M., & Boomsma, D. I. (2009). Born to be happy? The etiology of subjective well-being. Behavior Genetics, 39, doi: /s
Diener, E., Suh, E. M., Lucas, R. E., & Smith, H. L. (1999). Subjective well- being: Three decades of progress. Psychological Bulletin, 125, doi: /
Kendler, K. S., & Prescott, C. A. (2006). Genes, environment, and psychopathology: Understanding the causes of psychiatric and substance use disorders. New York, NY US: Guilford Press.
Weiss, A., Bates, T. C., & Luciano, M. (2008). Happiness is a personal(ity) thing: The genetics of personality and well-being in a representative sample. Psychological Science, 19, doi: /j x
Bivariate Common-Pathway Model
‣ The single latent personality factor had strong positive loadings on Extraversion, followed by Agreeableness and Openness, and a weaker negative loading on Neuroticism.
‣ Of the total heritability of SWB (i.e., 72%), 70% was shared with personality and 30% was unique to SWB. Individual-specific environmental effects accounted for 28% of the variance in SWB, of which 57% was shared with personality traits and 43% was unique to SWB.
Conclusion
We found one-third of genetic variation in SWB is distinctive from the genetic variation in personality. Thus, psychologists should be wary of labeling well-being a “personality thing.” Well-being and personality are best construed as members of the same family.