Question

A professor states that in the United States the proportion of college students who own iPhones is .66. She then splits the class into two groups: Group 1 with students whose last name begins with A-K and Group 2 with students whose last name begins with L-Z. She then asks each group to count how many in that group own iPhones and to calculate the group proportion of iPhone ownership. For Group 1 the proportion is p1 and for Group 2 the proportion is p2. To calculate the proportion you take the number of iPhone owners and divide by the total number of students in the group. You will get a number between 0 and 1. What would you expect p1 and p2 to be? Do you expect either of these proportions to be vastly different from the population proportion of .66? Would you be surprised if p1 was different than p2? Would you be surprised if they were the same or similar? What statistical concept describes the relationship between the first letter of someone's last name and whether or not they own an iPhone?

Answer 1