Probing Birth-Order Effects on Narrow Traits Using Specification-Curve Analysis

Abstract

The idea that birth-order position has a lasting impact on personality has been discussed for the past 100 years. Recent large-scale studies have indicated that birth-order effects on the Big Five personality traits are negligible. In the current study, we examined a variety of more narrow personality traits in a large representative sample ( n = 6,500-10,500 in between-family analyses; n = 900-1,200 in within-family analyses). We used specification-curve analysis to assess evidence for birth-order effects across a range of models implementing defensible yet arbitrary analytical decisions (e.g., whether to control for age effects or to exclude participants on the basis of sibling spacing). Although specification-curve analysis clearly confirmed the previously reported birth-order effect on intellect, we found no meaningful effects on life satisfaction, locus of control, interpersonal trust, reciprocity, risk taking, patience, impulsivity, or political orientation. The lack of meaningful birth-order effects on self-reports of personality was not limited to broad traits but also held for more narrowly defined characteristics.

Effects of Birth Order on Intelligence, Educational Attainment, Personality, and Risk Aversion in an Indonesian Sample

“…Our results were consistent with null effects on agreeableness, conscientiousness, extraversion, neuroticism, and risk aversion found in WEIRD populations (Damian & Roberts, 2015;Lejarraga et al, 2019;Rohrer et al, 2015). Yet, we found no effect of birth order on intelligence nor openness in contrast to the small negative estimates reported for WEIRD populations (Barclay, 2015b;Damian & Roberts, 2015;Rohrer et al, 2015;Rohrer et al, 2017). Additionally, the nonlinear effect of birth order on educational attainment was reversed compared to earlier studies.…”

No effect of birth order on adult risk taking

“…Sports statistics indicate that later-born children choose more risky sports and take more risks in baseball than firstborns. However, such a predisposition was not corroborated by Rohrer et al (16), whose specification curve analysis found no birth-order effect on risk taking in a large sample of adults. An important difference between the approaches of Sulloway (4) and Rohrer et al (16) is that the former analyzed behavioral data from sports choice and play, whereas the latter examined self-reported propensity to take risks.…”

“…However, such a predisposition was not corroborated by Rohrer et al (16), whose specification curve analysis found no birth-order effect on risk taking in a large sample of adults. An important difference between the approaches of Sulloway (4) and Rohrer et al (16) is that the former analyzed behavioral data from sports choice and play, whereas the latter examined self-reported propensity to take risks. In short, the effect of birth order on risk taking is still an open question, and the choice of the dependent measure may be crucial in answering the question of whether later-borns are more inclined to take risks: To date, birth-order effects have emerged only in behavioral data.…”

“…Against this background, Rohrer et al (16) used crosssectional data from the 2013 wave of the SOEP to explore whether birth order affects the self-reported propensity to take risks (as well as several personality traits beyond the Big Five traits). Using specification curve analysis (16,17), an exhaustive econometric approach, they observed, in contrast to previous findings on the selection of sports and risky play, that birth order had no substantive effect on risk taking, or indeed on the various personality dimensions examined. Recently, these results were supported in an Indonesian sample (9).…”

Does retirement affect secondary preventive care use? Evidence from breast cancer screening

“…The estimates from our preferred IV specification might be sensitive to several analytical choices, including the specification of the age trend, the sample selection or the definition of retirement. We assess the robustness of our results using a novel approach suggested by (see also for an overview and Rohrer et al (2017) for an application in psychology). They propose that researchers define an extensive set of a priori plausible specifications, which are then estimated and visualized in a so-called "specification curve".…”