within-subjects analysis of variance
a variation of the standard analysis of variance that is applied to data from a study in which the independent variable has multiple levels and each participant experiences each treatment level or is otherwise measured more than once (see within-subjects design). Because such designs involve recording multiple responses from the same person, it is necessary to examine how each individual varies in his or her responses, so as to separate such unique fluctuation from variation that is due to the influence of the treatment under investigation. For example, a researcher studying how amount of daily walking (e.g., none, 30 minutes, 60 minutes, 90 minutes) affects quality of sleep might have participants walk each length of time across consecutive weeks and then evaluate the results using a within-subjects analysis of variance. Also called repeated measures analysis of variance. Compare between-subjects analysis of
variance.