Hello. This question is incomplete, the complete question would be:
"You wish to know if drinking coffee while taking an exam will help students increase their score on the exam. Describe how you would design an experiment to answer this question. In your answer describe:
(a) Your independent variable and how you will manipulate it.
(b) Your dependent variable and how you will measure it.
(c) One specific thing that you will do to establish CONTROL in your experiment."
Answer:
In this experiment, I would determine how different amounts of coffee drunk by students before taking an exam would influence the exam score.
As we know, an independent variable is one that influences a result that will be observed, in this case my independent variable is the different amounts of coffee. To manipulate this variavés I would separate the students in equal groups, each group would receive a different amount of coffee that should be drunk about 20 minutes before the exam.
The dependent variable is one that is influenced to show a result. In the case of my experiment, the dependent variable would be the score that students would get on the exam. This variable would be measured by comparing the average score that members of one group achieved with the average score that other groups achieved.
An important thing to be established in an experiment is control. In the case of my experiment, a group of students would not receive any amount of coffee. As this group is not receiving the factor evaluated in the experiment, this group is the control group and the average score that this group achieves will also be compared with the average of the groups that consumed coffee, so that it can be observed if the coffee had any influence in the score.
