Problem
A researcher with the Department of Education followed a cohort of students who graduated from high school in a certain year, monitoring the progress the students made toward completing a bachelor's degree. One aspect of his research was to determine whether students who first attended community college took longer to attain a bachelor's degree than those who immediately attended and remained at a 4-year institution. The data in the table attached below summarize the results of his study. Complete parts a) through e) below. Click here to view the sample data. Click here to view Student's t-distribution table. a) What is the response variable in this study? What is the explanatory variable? A. The response variable is the time to graduate. The explanatory variable is the number of students. B. The response variable is the time to graduate. The explanatory variable is the use of community college or not. C. The response variable is the number of students. The explanatory variable is the time to graduate. D. The response variable is the use of community college or not. The explanatory variable is the time to graduate.
Solution
Step 1 ：The response variable in a study is the variable that is measured as the outcome of the study. In this case, the outcome being measured is the time it takes for students to graduate. The explanatory variable is the variable that is manipulated or observed to see its effect on the response variable. In this case, the variable being observed is whether the students first attended community college or not.
Step 2 ：Therefore, the correct answer is B. The response variable is the time to graduate. The explanatory variable is the use of community college or not.
Step 3 ：\(\boxed{\text{B. The response variable is the time to graduate. The explanatory variable is the use of community college or not.}}\)
