Exercise

Regression to the mean

A sample size that is too small will not reveal an effect or be representative of the population.

This exercise assesses regression to the mean, using one-sample t-tests of one group, on the amount of time employees have been in a job position.

The absent dataset, pwr, and ggplot2 packages have been loaded for you. The time spent as an employee in the absent dataset has been sub-organized into three samples. The smallsamp list contains a random sample of 15 data points, the largesamp list contains 400 data points, and the allsamp list contains all 740 data points.

Instructions 1/2

50 XP
  • 1
    • Run three one-tailed, one sample t-tests using each sample size list, smallsamp, largesamp, and allsamp, using t.test.
  • 2
    • Create a histogram using ggplot with eight bins of each sample size list.