In an experiment investigating the effects of performance standards on the intrinsic motivation of college students, male and female subjects were presented with one of two levels of a performance standard (constant or accelerating) in a number guessing task. During a free time period
after completion of the task, observations of the subjects' continued play with the number task were made. A self report questionnaire of intrinsic motivation was also administered. Subjects who were given an accelerating standard of performance spent significantly more time playing the
game during the free period than those who were given a constant standard. A similar difference was not obtained on the questionnaire. The results indicate that accelerating standards of performance can enhance intrinsic motivation and that questionnaire answers such as those used in prior
studies and the current one may not be adequate measures of intrinsic motivation.