Question

1. Which of the settings does not allow use of a matched pairs T procedure?

A) You interview both the instructor and one of the students in each of 20 introductory statistics classes and ask each how many hours per week homework assignments require.

B) None of the other options are correct.

C) You interview a sample of 15 instructors and another 15 students and ask each how many hours per week homework assignments require.

D) You interview 40 students in the introductory statistics course at the beginning of the semester and ask how many hours per week homework assignments require.

2. An owner of a home in the Midwest installed solar panels to reduce heating costs. After installing the solar panels, he measured the amount of natural gas used y (in cubic feet) to heat the home and outside temperature x (in degree‑days, where a day’s degree‑days are the number of degrees its average temperature falls below 65 ∘F) over a 23-month period. He then computed the least‑squares regression line for predicting y from x and found it to be ^y=85+16x.

By looking at the equation of the least‑squares regression line, you can see that the correlation between amount of gas used and degree‑days is

A) unable to be determined without seeing the data.

B) less than zero.

C) equal to zero.

D) greater than zero.

Answer 1