Example of a Valid Extreme Outlier

When a researcher finds that an extreme score in a dataset is valid and accurate (not an error), best practice is to run the analysis both with and without that score and, if the results differ substantially, report both sets of results.

A psychologist determines that an extreme outlier in their dataset is a valid and accurate measurement rather than a recording error. According to best practices in psychological research, how should the researcher manage this outlier to maintain both statistical robustness and transparency?

A psychology researcher is analyzing data from a study on stress levels and identifies an extreme, valid outlier. Match each specific research goal or finding with the most appropriate methodological action according to best practices.

A researcher studying the impact of sleep deprivation on cognitive performance identifies one participant with an extremely high score that is verified as accurate. To systematically analyze the influence of this valid outlier on the study's conclusions, arrange the following steps in the correct methodological order.

You are developing the data-management and reporting section of a pre-registration protocol for a psychological study on exceptional memory. You anticipate that some participants may produce valid but extreme scores that are accurate reflections of their performance. Which of the following reporting strategies should you construct to ensure the highest standards of transparency and robustness for these valid outliers?

Match each strategy for managing valid extreme outliers in psychological research with its correct description.

A psychology researcher identifies a valid extreme outlier in their dataset. When they compare their findings, the analysis with the outlier yields $p = .01$, while the analysis without it yields $p = .12$. To ensure the scientific community can properly evaluate the robustness and transparency of the findings, the researcher should report _____ sets of results in their final paper.

To accurately describe a dataset that includes valid extreme outliers without removing them, researchers can utilize _____ statistics, such as the median, which are specifically designed to be less sensitive to extreme values than other measures of central tendency.

A psychology researcher conducts a study on reaction times and identifies a valid extreme outlier. After running the analysis both with and without the outlier, the researcher observes that the statistical significance of the primary hypothesis test changes from $p = .02$ to $p = .15$. In this scenario, it is methodologically acceptable for the researcher to report only the analysis including the outlier, provided they justify that the score was verified as a valid, accurate estimate.

A researcher is studying cognitive performance and identifies a participant with a valid but extremely high score. To systematically evaluate and report the impact of this outlier on the study's conclusions, the researcher must follow a specific methodological sequence. Order the steps from first to last.

Identify and state the two primary strategies that psychological researchers can use to manage valid extreme outliers (scores that represent honest and accurate estimates rather than errors). Additionally, state what best practice dictates if a researcher compares analyses with and without these outliers and finds that the results differ substantially.

Based on best practices for handling valid extreme outliers, explain why using the mean as the primary descriptive statistic would be problematic in this case, and describe the two main options the psychologist has to manage and report this toddler's extreme score.

A research group studying reaction times finds a valid extreme outlier (a participant who is unusually slow but verified as accurate). They run their hypothesis test first with the outlier ($p = .02$) and then without it ($p = .15$). Based on best practices for data reporting, what specific action should the researchers take in their final report, and why?