A New, Near-Gaussian Measurement of Leftism Shows the Paternal Age Effect Replicates
OpenPsych , Aug. 8, 2025, ISSN: 2597-324X
Previously, we showed that there is a paternal age effect on leftism (increasing leftism with increasing age of father when born), using a binary classification based on three items regarding Black Lives Matter, LGBT, and feminism [1]. A major limitation of that study was the use of the binary measurement. In this paper, we show that the same effect is detectable with a new, near-Gaussian measurement of leftism. The correlation between this measurement and paternal age was r = 0.12 (p < 0.001). This measurement has high reliability (Cronbach’s α = 0.93) which far outperforms the commonly used Wilson-Patterson Conservatism Scale (α = 0.71) [2] as well as high criterion validity, as evidenced by the Cohen’s d between Republicans and Democrat on the measurement (d = 2.31, p < 0.001). Likewise, we show that, as before, there is no significant correlation between general leftism and age when having a child in fathers, suggesting this result is not due to older fathers being more leftist.
