Nature and Impact of Reference Group Effects in Personality Assessment Data.

People have a tendency to engage in social comparisons when evaluating and reporting on personality. This tendency and variation in who people compare their personality to is known as the reference group effect and has been largely discussed in cross-cultural research. However, reference group effects have implications beyond cross-cultural research and should be considered when collecting and interpreting personality data. In the present study, we examined the nature and impact of reference group comparisons on the Big Five personality traits in a sample of N = 1194 participants. Specifically, we examined what reference groups participants most believed they compared their personality to, and which reference group was actually the most impactful on trait scores. We found that most people believed they compared their personality to people in general. However, the most influential reference group was people the same age as the participants. Moreover, we found that people mostly engaged in between- as opposed to within-person comparisons when evaluating their own personality. Overall, our findings highlight that people have relatively little insight into the comparisons they engage in when make judgments on personality. Discussion focuses on theoretical and practical implications of our findings in light of personality assessment data.

National religiosity eases the psychological burden of poverty.

Lower socioeconomic status (SES) harms psychological well-being, an effect responsible for widespread human suffering. This effect has long been assumed to weaken as nations develop economically. Recent evidence, however, has contradicted this fundamental assumption, finding instead that the psychological burden of lower SES is even greater in developed nations than in developing ones. That evidence has elicited consternation because it suggests that economic development is no cure for the psychological burden of lower SES. So, why is that burden greatest in developed nations? Here, we test whether national religiosity can explain this puzzle. National religiosity is particularly low in developed nations. Consequently, developed nations lack religious norms that may ease the burden of lower SES. Drawing on three different data sets of 1,567,204, 1,493,207, and 274,393 people across 156, 85, and 92 nations, we show that low levels of national religiosity can account for the greater burden of lower SES in developed nations. This finding suggests that, as national religiosity continues to decline, lower SES will become increasingly harmful for well-being-a societal change that is socially consequential and demands political attention.

Self-other personality agreement and internalizing problems in adolescence.

OBJECTIVE: Achieving a clear self-view is a lifelong task that is particularly salient during adolescence. Theory and research suggest that close others' perceptions of individuals' personality may influence the formation and maintenance of coherent self-views. The degree to which adolescents develop a stable and coherent self-view, in turn, may have perennial influences on their mental health and well-being. This 1-year longitudinal study investigated the associations between the agreement of self- and other-rated Big Five personality traits and internalizing problems in adolescence. METHOD: Participants were 570 Dutch adolescents (51% girls), their mothers, friends, and siblings. We examined the cross-sectional and longitudinal associations between self-other personality agreement and internalizing problems using polynomial regression analyses and response surface analyses. RESULTS: Results indicated strong main effects of self- and other-rated personality traits on internalizing problems but provided little evidence for longitudinal associations between self-other personality agreement and internalizing problems. CONCLUSION: Our results cast doubt on the generalizability of the beneficial effects of self-other agreement documented in the adult literature to adolescents but highlight the importance of self- and other-rated personality in youth's mental health development. Discussion focuses on the theoretical implications and recommendations for future investigations of self-other agreement.

Using Machine Learning to Advance Personality Assessment and Theory.

Machine learning has led to important advances in society. One of the most exciting applications of machine learning in psychological science has been the development of assessment tools that can powerfully predict human behavior and personality traits. Thus far, machine learning approaches to personality assessment have focused on the associations between social media and other digital records with established personality measures. The goal of this article is to expand the potential of machine learning approaches to personality assessment by embedding it in a more comprehensive construct validation framework. We review recent applications of machine learning to personality assessment, place machine learning research in the broader context of fundamental principles of construct validation, and provide recommendations for how to use machine learning to advance our understanding of personality.

Openness to experience and culture-openness transactions across the lifespan.

We examined the life span development of openness to experience and tested whether change in this personality trait was associated with change in cultural activity, such as attending the opera or visiting museums. Data came from the Dutch Longitudinal Internet Study for the Social Sciences panel, which includes 5 personality assessments across a 7-year period of a nationally representative sample of 7,353 individuals, aged 16 to 95 years. Latent growth curve analyses indicated that on average, openness remained relatively stable in emerging adulthood before declining in midlife and old age. At each stage of life, there were significant individual differences in openness development, and changes in openness were correlated with changes in cultural activity. Autoregressive cross-lagged analyses indicated that increases in cultural activity precipitated increases in openness, and vice versa. These culture-openness transactions held across different age and education groups and when controlling for household income. We found less consistent codevelopmental associations between cultural activity and the other Big Five traits. We discuss the implications of these results for personality development theory and the role of cultural investment in personality trait change. (PsycINFO Database Record

Uncovering the Power of Personality to Shape Income.

The notion of person-environment fit implies that personal and contextual factors interact in influencing important life outcomes. Using data from 8,458 employed individuals, we examined the combined effects of individuals' actual personality traits and jobs' expert-rated personality demands on earnings. Results from a response surface analysis indicated that the fit between individuals' actual personality and the personality demands of their jobs is a predictor of income. Conclusions of this combined analysis were partly opposite to conclusions reached in previous studies using conventional regression methods. Individuals can earn additional income of more than their monthly salary per year if they hold a job that fits their personality. Thus, at least for some traits, economic success depends not only on having a "successful personality" but also, in part, on finding the best niche for one's personality. We discuss the findings with regard to labor-market policies and individuals' job-selection strategies.

What Drives the Development of Social Inequality Over the Life Course? The German TwinLife Study.

The German twin family study 'TwinLife' was designed to enhance our understanding of the development of social inequalities over the life course. The interdisciplinary project investigates mechanisms of social inequalities across the lifespan by taking into account psychological as well as social mechanisms, and their genetic origin as well as the interaction and covariation between these factors. Main characteristics of the study are: (1) a multidimensional perspective on social inequalities, (2) the assessment of developmental trajectories in childhood, adolescence, and young adulthood in a longitudinal design by using (3) a combination of a multi-cohort cross-sequential and an extended twin family design, while (4) capturing a large variation of behavioral and environmental factors in a representative sample of about 4,000 German twin families. In the present article, we first introduce the theoretical and empirical background of the TwinLife study, and second, describe the design, content, and implementation of TwinLife. Since the data will be made available as scientific use file, we also illustrate research possibilities provided by this project to the scientific community.