A data frame that is in the wide format. A hypothetical experiment is designed to measure effects of study time in a free-recall paradigm. In this hypothetical experiment, to-be-recalled 20-word lists are presented at a rate of 1, 2, or 5 sec per word. Of interest is the relation between study time and number of recalled list words. Suppose that the experiment is run as a within-subject (repeated-measures) design, including a total of 10 subjects, each of whom participated in all three study-time conditions.
recall.wideA data frame with 10 rows (each row corresponds to a subject) and 3 variables:
The number of words recalled under the first level of the experimental manipulation - 1 second exposure duration per word.
The number of words recalled under the second level of the experimental manipulation - 2 seconds exposure duration per word.
The number of words recalled under the third level of the experimental manipulation - 5 seconds exposure duration per word.
Loftus, G. R., & Masson, M. E. J. (1994). Using confidence intervals in within-subject designs. Psychonomic Bulletin & Review, 1, 476–490.