200 students volunteer for an experiment to test the effects o...

Question

200 students volunteer for an experiment to test the effects of sleep deprivation on memory recall. The students will be placed in one of five different treatment groups, including the control group.

Explain how you could design an experiment so that it uses a completely randomized design.

Accepted Answer

Welcome back, everyone. Researchers want to study the effects of different exercise routines on muscle strength. To conduct the experiment, they recruit 120 volunteers and a plan to assign them to one of three groups, including a control group. How can they design this experiment using a completely randomized design? A says they can randomly assign all participants to the exercise groups without considering any characteristics. B says to group participants based on age before assigning them to exercises. C says they can allow participants to choose the exercise routine they prefer, and the D says to assign the most active participants to the most intense exercise group. Now, to solve our problem, we first need to make sure we understand what it means to design an experiment using a completely randomized design. No, it, the, the, the answer lies in the words here. A completely randomized design assigns subjects to treatment groups completely or entirely by chance without considering any specific characteristics. And this design ensures that each participant has an equal chance of being assigned to any of the groups. So for it to be complete random. We could first list all 120 volunteers in a pool, OK? So we have our pool that we're choosing our volunteers from. Next, we can randomly assign each participant to one of the three exercise groups, including the control group, OK? So it's key there that we do this randomly. So, let's say then that we have our 3 groups that we're going to pull from our sample randomly, OK? And we also have to make sure that our random. that each group has an equal number of participants. So if you can count the dots here uh in in my illustration, you'll notice that each of them has a sample size of 5, OK. And this way Each group now has an equal number of participants, and this could be done by using randomization techniques like drawing lots or using a random number generator. So we could assign a number to each person in the volunteer pool and choose randomly any number that we get. And once we do this, then we can conduct the exercise intervention according to the assigned group and measure the muscle strength of participants after a specific period. This design avoids bias by giving each participant an equal opportunity to be in any group which makes the results more reliable and generalizable. Therefore, A is the correct answer. We we can design this experiment using a completely randomized design by randomly assigning all participants to the exercise groups without considering any characteristics. Thanks a lot for watching everyone. I hope this video helped.

200 students volunteer for an experiment to test the effects of sleep deprivation on memory recall. The students will be placed in one of five different treatment groups, including the control group.
Explain how you could design an experiment so that it uses a completely randomized design.

Key Concepts

Completely Randomized Design

Random Assignment

Control Group

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