Experimental Designs

Question 162587 • NC-Math 4 CR

Which statement about the randomization for the matched pairs design is correct?

Answer

For each participant, the nutritionist should flip a coin. If the coin lands on heads, the participant will be assigned to exercise during the first month and drink energy drinks during the second month. If the coin lands on tails, the participant will be assigned to drink energy drinks during the first month and exercise during the second month.

The nutritionist should place the names of the 50 participants on slips of paper and put them in a hat. She should then draw out 25 of the slips. Those participants will exercise for both months. The remaining 25 participants will drink energy drinks for both months.

The nutritionist should let the participants decide which treatment they would like to do first. That way, if they are too busy to exercise 30 minutes each day during the current month, they can save that treatment for the second month.

Because there are two treatments, exercise and drinking energy drinks, the nutritionist should divide the participants into 4 groups: 2 months of exercise, 2 months of energy drinks, 1 month of exercise followed by 1 month of energy drinks, and 1 month of energy drinks followed by 1 month of exercise. She can draw names from a hat to assign the participants to these 4 groups.

Explanation

In a matched pairs design, each participant receives both treatments, so the comparison is made within the same person. The order should be randomized to reduce the effect of changes over time; flipping a coin assigns each participant to exercise first or energy drinks first. Choice A correctly randomizes the treatment order for every participant.

AI-written and checked against the verified answer.

More from this Course

Scope of Inference

Warm-Up

Instruction