A Researcher Computes a One-Sample Z Test in Two Studies

question 58

Multiple Choice

A researcher computes a one-sample z test in two studies.Both studies used the same alpha level,placed the rejection region in both tails,and measured the same sample mean.The researcher selects a sample of 30 participants in Study 1 and decides to retain the null hypothesis.She selects a sample of 60 participants in Study 2 and decides to reject the null hypothesis.Which of the following is the best explanation for why the decision was different in Study 1 and Study 2?

• A) The different decisions in Study 1 and Study 2 are not possible because all values were the same.
• B) The different decisions in Study 1 and Study 2 are not possible because the researcher tested the same hypothesis.
• C) The different decisions in Study 1 and Study 2 are due to an error the researcher made in the first hypothesis test.
• D) The different decisions in Study 1 and Study 2 are possible because the second test was associated with greater power to detect an effect.

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Definitions:

Bay of Pigs

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The tendency for a group to make decisions that are more extreme than the initial inclination of its members, often observed after group discussions.

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Encourage Doubt

To promote questioning or skepticism about certain beliefs or assumptions.