This is also given Exercise. For each of the examples given here, decide whether the study was an observational study or a randomized experiment.

a. A group of students who were enrolled in an introductory statistics course were randomly assigned to take a web-based course or to take a traditional lecture course. The two methods were compared by giving the same final examination in both courses.

b. A group of smokers and a group of nonsmokers who visited a particular clinic were asked to come in for a physical exam every 5 years for the rest of their lives to monitor and compare their health status.

c. CEOs of major corporations were compared with other employees of the corporations to see if the CEOs were more likely to be the first child born in their families than were the other employees.

Exercise
For each of the examples given here, decide whether the study was an observational study or a randomized experiment.

a. A group of students enrolled in an introductory statistics course were randomly assigned to take either a web based course or a traditional lecture course. The two methods were compared by giving the same final examination in both courses.

b. A group of smokers and a group of nonsmokers who visited a particular clinic were asked to come in for a physical exam every 5 years for the rest of their lives to monitor and compare their health status.

c. CEOs of major corporations were compared with other employees of the corporations to see if the CEOs were more likely to have been the first child born in their families than were the other employees.