Abstract
Two experiments investigated the effect of repetition of instructional information on task errors. In Exp. 1, the number of repetitions was varied over a wide range to determine the functional relation between effectiveness of instructions and number of repetitions. The form of the repetition was also varied (rewording of important information versus an example). The relationship between effectiveness and number of repetitions was a negatively accelerated function and an example was more effective than reworded information, at least when the information was not repeated many times. Exp. 2 was similar to Exp. 1 except that the number of repetitions was a between-subjects variable instead of a within-subjects variable. Exp. 2 confirmed that the function relating effectiveness to number of repetitions is a negatively accelerated function.