Answer
The company mostly uses the mean while the union uses the median (number of sick days). The mean will likely be higher, because the data likely is right-skewed, for some employees may have more sick days than the others.
Work Step by Step
The company mostly uses the mean while the union uses the median (number of sick days). The mean will likely be higher, because the data likely is right-skewed, for some employees may have more sick days than the others.