Professor Okamoto is interested in the effects of prosocial TV on sharing behavior among preschool children. (Prosocialactions are meant to benefit others, not oneself.) She assembles a sample of 100 children, then assigns each child at random to either the prosocial TV group or the neutral TV group. The first group then views 30 minutes of TV with a prosocial theme, and the second group views 30 minutes of TV with a neutral theme. After the children finish their TV session, Professor Okamoto assigns them to __________.