Suppose a pharmaceutical company is designing an experiment to test their new allergy medication. They divide the 200 subjects by gender and then randomly assign the men and women to either receive the medication or a placebo. What purpose does blocking by gender serve? Choose the correct answer below. OA. Blocking insures that individuals do not adjust their behavior in some way to the treatment they are receiving. B. Blocking insures that the effect of a treatment is not due to some characteristic of a single experimental unit. OC. Blocking insures that the effect of factors whose levels cannot be controlled is minimized. OD. Blocking reduces the variability in the response variable and removes potential confounding caused by gender.
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Blocking is a technique used in experimental design to reduce the variability of the experimental results by accounting for known sources of variation. It involves dividing the experimental units into homogeneous groups (blocks) based on a characteristic that is Show more…
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A pharmaceutical company is designing an experiment to test their new allergy medication. They divide the 200 subjects by gender and then randomly assign men and women to either receive the medication or a placebo. What purpose does blocking by gender serve? Select one. A) Blocking insures that the effect of a factor is not due to some characteristic of an individual. B) Blocking insures that the effect of factors whose levels cannot be controlled is minimized. C) Blocking insures that individuals do not adjust their behavior in some way to the treatment they are receiving. D) Blocking reduces the variability in the response variable and removes potential confounding caused by gender.
Rashmi S.
When conducting an experiment to test the effectiveness of a new vaccine, a researcher chooses to use blocking, with men in one block and women in another block. How does this use of blocking help the experiment?
Madhur L.
Researchers are interested in testing whether a video game that is designed to increase brain activity actually works. To test this, they plan to randomly assign subjects to either the treatment group (spend 15 minutes per day playing the game) or a control group (spend 15 minutes per day surfing the Web). At the end of the study, the researchers will administer a test of "brain teasers" to see which group has the greater mental agility. Because they suspect that age might affect the outcome, the researchers will create blocks of ages: $18-25,26-35,36-45$, and $46-55$. To randomly assign subjects to treatment or control, they will place four tickets in a box. The tickets are labeled with the age groups. When an age group is selected, everyone in that age group will be assigned to the treatment group. They will select two age groups to go to treatment, and two to go to control. Is this an appropriate use of blocking? If so, explain why. If not, describe a better blocking plan.
Adi S.
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