When Two Groups Have Very Different Means, It Is Best

question 47

Multiple Choice

When two groups have very different means, it is best to compare their

• A) Standard deviation.
• B) Mean.
• C) Median.
• D) Coefficient of variation.

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Definitions:

Regression Toward the Mean

A statistical phenomenon where extreme scores on a variable tend to be closer to the mean upon subsequent measurements.

One-group Pretest-posttest Design

An experimental design where a single group of participants is tested before and after an intervention to assess its effect.

Extreme Scores

Extreme scores refer to the most unusually high or low values in a data set, which can significantly influence statistical analyses and interpretations.

Selection Differences

Disparities between groups in an experimental study that can affect the outcome, often resulting from non-random assignment.