Chapter 7, Problem 16E

(a)

To determine

To find out is it appropriate to calculate the correlation and explain.

Answer to Problem 16E

Yes.

Explanation of Solution

Yes, it is appropriate to calculate the correlation because the points generally move in an upward direction from left to right. Even though there is an outlier i.e. the right most point, but it won't affect the correlation because there are many points in the scatterplot.Also we are dealing with the quantitative figures. Thus, it is appropriate to calculate the correlation.

(b)

To determine

To explain what you have learned about results of these experiments.

Explanation of Solution

It is given that the correlation between drug improvement and placebo improvement is $0.898$ .

The greater the improvement in the patients who were treated in placebo, the greater their improvement when treated with the real drug. Thus, it shows a linear positive correlation between the two as the points in the scatterplot is moving in the upward direction. Also, the correlation is close to one thus, the relationship is nearly strong.