Suppose that for the population of UNCG students, the mean of GPA is 3.46 and the median of GPA is 3.02. if you randomly select a student from the population, the expected value of his or her GPA is equal to 3.46.
In sample sampling all doable samples of a given size are equally possible to be chosen.When sampling while not replacement, the sample observation can not be chosen into your sample multiple times.