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 Fatigue, boredom, and subjects becoming over familiarized with a study, are all progressive errors (Myers & Hansen, 2012). One way to minimize some progressive errors in a study may be to counterbalance procedures. To do this, researchers should distribute errors across different treatment conditions (Myers & Hansen, 2012). Another way to control progressive errors is to present all the treatment conditions to each participant (Myers & Hansen, 2012). In addition to these ways to minimize progressive errors, the researchers can use reverse counterbalancing to ensure participants are not familiarizing themselves with a condition or order, which in turn would allow them to “practice” (Myers & Hansen, 2012). Overall, participants in a within-subject design are being included in all the treatment conditions which can make them more exhausted or become bored with the treatments.