Milieu Effects on the Dark Triad Traits and Their Sex Differences in 49 Countries

Most research on the development of personality traits like the Dark Triad (i.e., narcissism, Machiavellianism, and psychopathy) focuses on local effects like parenting style or attachment, but people live in a larger society that may set the stage for any local effects. Here we paired nation-level data on the traits from 49 nations with several milieu indicators (e.g., life expectancy, homicide rates) from three timepoints (and change among them) where the average participant (≈ 22yo) would have been a child (≈ 6yo), a pre-teen (≈ 11yo), and a teenager (≈ 16yo). Congruent with previous research, variance in narcissism was far more sensitive to variance in milieu conditions in general and across all three time points than variance in Machiavellianism or psychopathy. The milieu conditions differentiated the traits somewhat with income and education revealing negative correlations with narcissism, positive correlations with Machiavellianism, and null correlations with psychopathy. Sex differences in Machiavellianism and narcissism were correlated with homicide rates across the three timepoints. The evidence that changes in milieu conditions in ones' past predicts the traits was erratic, but larger sex differences in the traits were associated with decreased life expectancies and homicide rates between childhood and pre-teens.</p

Milieu effects on the Dark Triad traits and their sex differences in 49 countries

Most research on the development of personality traits like the Dark Triad (i.e., narcissism, Machiavellianism, and psychopathy) focuses on local effects like parenting style or attachment, but people live in a larger society that may set the stage for any local effects. Here we paired nation-level data on the traits from 49 nations with several milieu indicators (e.g., life expectancy, homicide rates) from three timepoints (and change among them) where the average participant (≈ 22yo) would have been a child (≈ 6yo), a pre-teen (≈ 11yo), and a teenager (≈ 16yo). Congruent with previous research, variance in narcissism was far more sensitive to variance in milieu conditions in general and across all three time points than variance in Machiavellianism or psychopathy. The milieu conditions differentiated the traits somewhat with income and education revealing negative correlations with narcissism, positive correlations with Machiavellianism, and null correlations with psychopathy. Sex differences in Machiavellianism and narcissism were correlated with homicide rates across the three timepoints. The evidence that changes in milieu conditions in ones' past predicts the traits was erratic, but larger sex differences in the traits were associated with decreased life expectancies and homicide rates between childhood and pre-teens

Structure of Dark Triad Dirty Dozen Across Eight World Regions

The Dark Triad (i.e., narcissism, psychopathy, Machiavellianism) has garnered intense attention over the past 15 years. We examined the structure of these traits’ measure—the Dark Triad Dirty Dozen (DTDD)—in a sample of 11,488 participants from three W.E.I.R.D. (i.e., North America, Oceania, Western Europe) and five non-W.E.I.R.D. (i.e., Asia, Middle East, non-Western Europe, South America, sub-Saharan Africa) world regions. The results confirmed the measurement invariance of the DTDD across participants’ sex in all world regions, with men scoring higher than women on all traits (except for psychopathy in Asia, where the difference was not significant). We found evidence for metric (and partial scalar) measurement invariance within and between W.E.I.R.D. and non-W.E.I.R.D. world regions. The results generally support the structure of the DTDD