Summary of individual difference variables.

The working memory score indexes the number of items that subjects can hold in memory, the cognitive flexibility score represents the additional time required to connect alternating numbers and letters versus sequential numbers, and the numeracy score represents the number of correct answers out of 11 total items. Risk aversion and loss aversion are indices between 0 and 12 that represent the switching point in lottery questions involving choices between sure outcomes and gambles (see Supplementary Methods). Income, debt, and assets are based on ordered categories (e.g., an income rating of 6 corresponds to an average household income of $60,000–$79,000 and a rating of 7 corresponds to $80,000–$99,000; a debt rating of 7 corresponds to $20,000–$39,999 and a rating of 8 corresponds to $40,000–$59,999; and an assets rating of 13 corresponds to $200,000–$499,999).