Understanding Basic Statistics 6th Edition by Charles Henry Brase,Corrinne Pellillo Brase

Exercise 13

Critical Thinking Suppose you are assigned the number 1, and the other students in your statistics class call out consecutive numbers until each person in the class has his or her own number. Explain how you could get a random sample of four students from your statistics class.
(a) Explain why the first four students walking into the classroom would not necessarily form a random sample.
(b) Explain why four students coming in late would not necessarily form a random sample.
(c) Explain why four students sitting in the back row would not necessarily form a random sample.
(d) Explain why the four tallest students would not necessarily form a random sample.