Which Kid gonna Pass the Test?

The Stanford marshmallow experiment was a series of studies on delayed gratification in the late 1960s and early 1970s led by psychologist Walter Mischel, then a professor at Stanford University. In these studies, a child was offered a choice between one small reward provided immediately or two small rewards if they waited for a short period, approximately 15 minutes, during which the tester left the room and then returned. (The reward was sometimes a marshmallow, but often a cookie or a pretzel.) In follow-up studies, the researchers found that children who were able to wait longer for the preferred rewards tended to have better life outcomes, as measured by SAT scores, educational attainment, body mass index (BMI), and other life measures. A replication attempt with a more diverse sample population over 10 times larger than the original study showed only half the effect size of the original study and suggested that economic background rather than willpower explained the other half of the variation.

Test

Test subjects were 16 boys and 16 girls attending the Bing Nursery School of Stanford University. Three other subjects were run, but eliminated because of their failure to comprehend the instructions. The children ranged in age from 3 years, 6 months to 5 years, 8 months (with a median age of 4 years, 6 months). The procedures were conducted by two male experimenters. Eight subjects (four male and four female) were assigned randomly to each of the four experimental conditions. In each condition each experimenter ran two boys and two girls in order to avoid systematic biasing effects from sex or experimenters.

Conditions

Both the immediate (less preferred) and the delayed (more preferred) reward were left facing the subject and available for attention
Neither reward was available for the subject's attention, both rewards having been removed from sight
The delayed reward only was left facing the subject and available for attention while he or she waited
The immediate reward only was left facing the subject and available for attention while he or she waited


In follow-up studies, Mischel found unexpected correlations between the results of the marshmallow test and the success of the children many years later. The first follow-up study, in 1988, showed that "preschool children who delayed gratification longer in the self-imposed delay paradigm, were described more than 10 years later by their parents as adolescents who were significantly more competent."