James Heckman

The Heckman correction addresses sample-selection bias when the observed sample is not randomly drawn from the population of interest. Its two-step form first models selection and then adds a correction term to the outcome equation.

Heckman was honored for developing theory and methods for analyzing selective samples. He shared the prize with Daniel McFadden, who was recognized for methods used to analyze discrete choices.

Heckman argues that high-quality early interventions can produce lasting gains, especially for disadvantaged children. His work also emphasizes that later investments can complement early development rather than treating preschool as a stand-alone cure.

The phrase usually refers to Heckman's argument that investment in early skills can generate strong social returns through better education, health, employment, and behavior. It is a policy summary of a broader body of research, not a single universal return guaranteed for every preschool program.