Physicians take a sample of smokers and nonsmokers and

Last updated: 7/9/2022

Physicians take a sample of smokers and nonsmokers and record the time it takes them to fall asleep on seven consecutive nights. What is the variable of interest? A. The physicians B. The average time it takes to fall asleep on the seven nights C. The smokers and nonsmokers D. The amount of time it takes to fall asleep each night