Predicting mid-life capital formation with pre-school delay of gratification and life-course measures of self-regulation

113 participants of the 1967-1973 Stanford Bing preschool delay studies, surveyed in their late forties (72% of those contacted, from a full sample of 543)

United States; the original marshmallow cohort at about age 45-50.

A preregistered analysis plan with a newly constructed preregistered delay measure and a preregistered composite self-regulation index, Bayesian shrinkage for multiple testing across eleven outcomes. Two limitations - the data cannot be shared for consent reasons, and the diagnostic-condition subsample is only 34 of 113. Outcomes are self-reported net worth, permanent income, absence of high-interest debt, savings rate, forward-looking behaviours and educational attainment.

Preschool delay of gratification does NOT predict any of the eleven mid-life capital-formation outcomes; the sign-adjusted average correlation is 0.02. The composite index combining preschool delay with self-regulation surveys at ages 17, 27 and 37 predicts 10 of 11 outcomes in the expected direction with an average correlation of 0.19, six of them at p < .05. Critically, the authors state that including the preschool delay measure in that composite does not affect the index's predictive power - the childhood measure adds nothing.

High for the composite index, which is observational. The preschool null is a null regardless.

Not applicable as an extension rather than a replication, but it is consistent with Watts, Duncan and Quan 2018 and it is unusually informative because Mischel, Shoda and Peake are among its authors - the originators reporting that their own famous predictor does not survive to mid-life.