
Concept explainers
(a)
Explain when the t test for independent means should be used.
(a)

Explanation of Solution
The t test for independent means:
When two groups of people who are not dependent on each other are tested for defined hypothesis then the t test for independent means must be used. In this study the variance of the population is not known.
(b)
Explain how t test for independent means is different from t test for dependent means.
(b)

Explanation of Solution
The t test for dependent means:
When each of the participants in hypothesis testing is measured twice, or some dependent participants are paired, the t test for dependent means is used. In other words, t test for dependent means is used when participants has two different scores such as ‘before and after’ with the unknown population variance.
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Chapter 8 Solutions
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