Chapter 4.3, Problem 99E

(a)

To determine

To calculate the difference (Clipboard A minus Clipboard B) in the mean number of days for the two groups.

Answer to Problem 99E

  $0.47$ is the mean difference of responses from Clipboard A and B.

Explanation of Solution

Michael wanted to conduct a survey to examine that are people influenced by the other people or not. Thus in this survey two clipboards were assigned to different groups of people and result was noted. For the Clipboard A the mean response for the group was $4.68$ and for the Clipboard B the mean response for the group was $4.21$ .

Thus the difference in the mean of the two clipboards can be calculated as:

Mean of Clipboard A minus Mean of Clipboard B.

Thus, we have:

  $\begin{array}{l}=4.68-4.21\\ =0.47\end{array}$

Thus, we have $0.47$ is the mean difference of responses from Clipboard A and B.

(b)

To determine

To explain what does the dot $0.72$ means in this context.

Explanation of Solution

The dot $0.72$ means that the difference in the Clipboard A and B is more. We can say that the responses mentioned for the question is very different from each other. The Clipboard A is more than the Clipboard B nut there is only one or two dots that is the gap in the responses of both the clipboards is more but at very few questions.

(c)

To determine

To use the result of the simulation to find out if the difference in means from part (a) is statistically significant or not and explain.

Explanation of Solution

The difference in means from part (a) is statistically not significant as there are other factors that can be involved in the study which can influence the result. So, just by looking at the differences cannot solve the accuracy of the result. Thus, we should consider other methods also to evaluate the survey that can give better result. And also that the study is deemed statistically significant if there's a very low probability the result could have occurred by chance.