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Chapter 12: Q. 20 (page 802)

Random assignment is part of a well-designed comparative experiment because

(a) It is more fair to the subjects.

(b) It helps create roughly equivalent groups before treatments are imposed on the subjects.

(c) It allows researchers to generalize the results of their experiment to a larger population.

(d) It helps eliminate any possibility of bias in the experiment.

(e) It prevents the placebo effect from occurring

Short Answer

Expert verified

Correct option is (b), It helps create roughly equivalent groups before treatments are imposed on the subjects.

Step by step solution

01

Given

We need to explain reason of random assignment as part of well-designed comparative experiment.

02

Step 2:Explanation

In experimental research,random assignment is a way of placing participants from your sample into different treatment groups using randomization.

Random assignment is part of comparative experiment as it helps you ensure that all groups are comparable at the start of a study, any differences between them are due to random factors.

Hence, option (b) is correct answer.

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Most popular questions from this chapter

Foresters are interested in predicting the amount of usable lumber they can harvest from various tree species. They collect data on the diameter at breast height (DBH) in inches and the yield in board feet of a random sample of 20Ponderosa pine trees that have been harvested. (Note that a board foot is defined as a piece of lumber 12inches by 12inches by 1inch.) A scatterplot of the data is shown below

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(e) the probability of making a Type II error is0.0087.
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