Rolf Degen summarizing... Contrary to earlier views, the big five personality traits are distributed largely evenly across the different social classes

Hughes, Bradley T., Cory K. Costello, Joshua Pearman, Pooya Razavi, Cianna Bedford-Petersen, Rita M. Ludwig, and Sanjay Srivastava. 2021. “The Big Five Across Socioeconomic Status: Measurement Invariance, Relationships, and Age Trends.” PsyArXiv. May 26. doi:10.31234/osf.io/wkhfx

Abstract: Associations between socioeconomic status (SES) and personality traits have important implications for theory and application. Progress in understanding these associations depends on valid measurement, unbiased estimation, and careful assessment of generalizability. In this registered report, we used data from AIID, a large online study, to address three basic questions about personality and SES. First, we evaluated the measurement invariance of a common measure of personality, the Big Five Inventory, across indicators of educational attainment, income, and occupational prestige. Fit indices showed some instances of detectable noninvariance, but with little practical impact on substantive results. Second, we estimated associations between SES and personality. Results showed that personality and SES were largely independent (most rs < .1), in contrast to predictions derived from several previous studies. Third, we tested whether age trends in personality were moderated by SES. Results did not support predictions from social investment theory, but they did suggest that age trends were largely generalizable across SES. We discuss the implications of these findings for developing and validating personality measures for use in diverse samples. We also discuss the implications for theories that propose that the Big Five are responsive to, or partially responsible for, people’s economic and social conditions.