PSY/ Statistics

1. Based on the scale of measurement for each variable listed below, which measure of central tendency is most appropriate for describing the data?

a. The time (in years) it takes a sample of students to graduate college.

b. The blood type (such as A, B, AB, or O) of a group of participants.

c. The rankings of college undergraduate academic programs.

2. How do the sample mean and the population mean differ? What is the symbol for each type of mean?