Power Analysis

Which of the following best describes what is evaluated by statistical validity in a research study?

Match each component of statistical validity with the role it plays in evaluating psychological research results.

A psychology researcher wants to compare the average reaction times of three different groups: a low-caffeine group, a high-caffeine group, and a no-caffeine control group. If the researcher chooses to use a $t$-test to analyze the differences among these three groups, they are maintaining high statistical validity.

Arrange the following steps in the logical order a researcher must follow to ensure their numerical conclusions are sound and their statistical treatments are correct, beginning with the initial categorization of data.

Imagine you are designing a study to determine if three different study environments ('silent', 'classical music', or 'white noise') produce different average scores on a memory test measured on a ratio scale from $0$ to $100$. Which of the following research plans would you construct to ensure the highest level of statistical validity for your final conclusions?

A researcher can guarantee high statistical validity simply by choosing the correct inferential test, regardless of whether the sample size is adequate or the mathematical assumptions of the test are met.

A researcher finds a significant difference between two groups using a $t$-test ($p = 0.04$), but a critic argues the results are unsound because the data violated the test's mathematical assumptions and the sample size was too small. By judging the soundness of the researcher's numerical conclusions in this way, the critic is focusing on the study's _____ validity.

A researcher wants to compare the scores of two groups using a $t$-test. To ensure the study has high statistical validity, the researcher must not only select the correct test but also verify that the data does not violate the underlying mathematical _____ of that test.