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Chapter 4: Q 102. (page 269)

Random sampling versus random assignment Explain the difference between the types of

inference that can be made as a result of random sampling and random assignment.

Short Answer

Expert verified

Because random sampling is typical of the entire group, inferences about the population can be made. Because random assignment reduces variability, it enables inferences about cause and effect.

Step by step solution

01

Given information

We must distinguish between the different types of inferences that can be drawn from random sampling and random assignment.

02

Concept

Most statistical studies try to draw conclusions that go beyond the data itself. In order to make population inferences, participants in a study must be randomly picked from the greatest population. Cause and effect can be inferred from a well-designed experiment in which treatments are randomly assigned to experimental units.

03

Explanation

We must distinguish between the types of inferences that can be drawn from random sampling and random assignment in order to answer the question. As a result, because random sampling is typical of the entire group, inferences about the population can be made. Because random assignment reduces variability, it enables for inferences about cause and effect.

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