Chapter 13, Problem 6E

a)

To determine

To find the type of the study.

Answer to Problem 6E

This is an experimental study.

Explanation of Solution

First need to understand about the experimental study and observational study:

Experimental study: Assigning people or things to groups and applying some treatment to one group, while the other group does not receive the treatment.

Observation study: In an observational study, measure or survey members of a sample without trying to affect them.

This is an experimental study because the treatment is replacing the flower pictures with picture of eyes.

b)

To determine

To identify the variables.

Answer to Problem 6E

The variables are Picture and average contribution.

Explanation of Solution

In this study, an investigation is replacing pictures and their average contribution. Therefore, the variables are Picture and average contribution.

c)

To determine

To explain meaning of “increased significantly”.

Explanation of Solution

The meaning of “increased significantly” is that the increases in the average contribution is too large to be due to chance.