Question

A group of researchers is designing an experiment to test whether meditation helps people fall asleep faster. The researchers selected a sample of 150 people, and over the next two months, 75 of them will meditate nightly for 15 minutes before going to bed whereas the remaining 75 will follow their normal bedtime routine. At the end of the two months, the researchers will compare the average length of time it takes each group to fall asleep.

Why is it important that the researchers use randomization to assign each of the people to a treatment group? (select all that apply)

1) Randomization eliminates the variation contributed by confounding variables in the study.

2) Randomization prevents the people from selecting their own treatment group.

3) Randomization prevents the researchers from specifically assigning all people who regularly fall asleep quickly to meditate nightly for 15 minutes before going to bed.

4) Randomization ensures that there will be an equal number of people in each treatment group.

5) Randomization ensures each treatment group will be similar in everything except whether or not they meditate before bed.

Answer 1

We know that,

Randomization eliminates the variation contributed by confounding variables in the study.

Also

Randomization prevents the people from selecting their own treatment group.

And last

Randomization prevents the researchers from specifically assigning all people who regularly fall asleep quickly to meditate nightly for 15 minutes before going to bed.

Thank you.