The reason that a population mean and the mean of a random sample selected from that population might be different is that the sample mean is found by dividing by n-1 while the population mean is found by dividing by n.

Question

Quizplus · Accepted Answer

The difference between a population mean and a sample mean is due to sampling variability, not because of the difference in division by n or n-1. The division by n-1 is used in the calculation of a sample variance, not the sample mean.

The Reason That a Population Mean and the Mean of a Random