A professor wants to know how undergraduate students at X University feel about food services on campus, in general. She obtains
a list of email addresses of all 15,000 registered undergraduates from the registrar’s office and mails a questionnaire to 300 students selected at random. Only 150 questionnaires are returned. What is the size of the population?
Given that a professor wants to know how undergraduate students at X University feel about food services on campus, in general. She obtains a list of email addresses of all 15,000 registered undergraduates from the registrar’s office and mails a questionnaire to 300 students selected at random.
Only 150 questionnaires are returned.
So the sample size changed to 150. But population is the number of registered undergraduates which do not change.
