The marshmallow test, redone with ten times as many children, found that a four-year-old's willpower mostly stopped predicting teenage success once family background was taken into account
Space Daily • • health
Key Points:
- A 2018 study with a larger and more diverse sample found that the predictive power of the marshmallow test on later achievement is much weaker than originally reported, especially after accounting for family background and early cognitive ability.
- The original 1990 study had a small, selective sample from Stanford, while the replication analyzed 918 children, focusing on 552 from less-educated mothers to better represent the general population.
- The replication showed that the ability to delay gratification at age four had only a faint association with adolescent achievement and little to no significant link with behavioral outcomes at age fifteen.
- Much of the marshmallow test's predictive value comes from whether a child can wait a short initial period (around 20 seconds), rather than the full delay, challenging the popular narrative of heroic self-control.
- The findings suggest that delay of gratification reflects a child's environment and circumstances more than a stable character trait, complicating the simple moral that early patience alone determines future success.
