Chapter 11.6, Problem 12E

To determine

whether the experimental difference is positive, negative, or zero.

Answer to Problem 12E

The experimental difference is negative; it shows that the treatment is slightly effective.

Explanation of Solution

Given:

  

Calculation:

In this question determine whether the experimental difference, ${\overline{x}}_{treatment}-{\overline{x}}_{control}$ is positive, negative, or zero, without calculating.

From the given double dot plot, it is clear that most of the treatment values are less than most of the control values. Thus, the difference will be negative.

Hence, the experimental difference ${\overline{x}}_{treatment}-{\overline{x}}_{control}$ is negative.

Since, the experimental difference is negative; it shows that the treatment is slightly effective.

Conclusion:

The experimental difference is negative; it shows that the treatment is slightly effective.