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Chapter 4: Q. 84 (page 268)

In the experiment of the preceding exercise, the subjects were randomly assigned to the

different treatments. What is the most important reason for this random assignment?

a. Random assignment eliminates the effects of other variables such as stress and body

weight.

b. Random assignment is a good way to create groups of subjects that are roughly

equivalent at the beginning of the experiment.

c. Random assignment makes it possible to make a conclusion about all men.

d. Random assignment reduces the amount of variation in blood pressure.

e. Random assignment prevents the placebo effect from ruining the results of the study.

Short Answer

Expert verified

Option b is correct answer: Random assignment is a good way to create groups of subjects that are roughly equivalent at the beginning of the experiment.

Step by step solution

01

Given Information

We need to find out reason for random assignment to different treatments in preceding exercise.

02

Explanation

In an experiment, random assignment is used to assign people to the control and treatment groups by chance. This procedure ensures that the groups are equal at the start of the investigation, making it safer to assume that the treatments are to blame for any differences observed by the experimenters at the end. As a result option b is correct answer.

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Most popular questions from this chapter

SRS of students? At a party, there are 30 students over age 21 and 20students underage21. You choose at random 3 of those over 21 and separately choose at random 2 of those under 21 to interview about their attitudes toward alcohol. You have given every student at the party the same chance to be interviewed. Is your sample an SRS? Explain your answer.

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