Productivity of workers with and without a coffee break
Data for Exercise 7.55
Coffee
A data frame/tibble with nine observations on three variables
workers' productivity scores without a coffee break
workers' productivity scores with a coffee break
with minus without
Kitchens, L. J. (2003) Basic Statistics and Data Analysis. Pacific Grove, CA: Brooks/Cole, a division of Thomson Learning.
qqnorm(Coffee$differences) qqline(Coffee$differences) shapiro.test(Coffee$differences) t.test(Coffee$with, Coffee$without, paired = TRUE, alternative = "greater") wilcox.test(Coffee$with, Coffee$without, paired = TRUE, alterantive = "greater")
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