SleepCaffeine: Sleep Caffeine

Description Format Details Source Examples


Experimentn to compare word recall after sleep or caffeine


A data frame with 24 observations on the following 2 variables.

  • Group Treatment: Caffeine Sleep

  • Words Number of words recalled


A random sample of 24 adults were divided equally into two groups and given a list of 24 words to memorize. During a break, one group takes a 90 minute nap while another group is given a caffeine pill. The response variable is the number of words participants are able to recall following the break.


Mednick, Cai, Kanady, and Drummond, "Comparing the benefits of caffeine, naps and placebo on verbal, motor and perceptual memory", Behavioural Brain Research, 193 (2008), 79-86.



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