Which of the following indicates how compressed or expanded the distribution of scores is?

• A. Measures of Position
• B. Measures of Central Tendency
• C. Measures of Correlation
• D. Measures of Variability

Answer: (D)

Spread in a distribution, or how clustered the scores are, is captured by measures of variability. These describe dispersion around the center, telling you whether scores are tightly packed or widely spread. Examples include range, variance, standard deviation, and interquartile range. In contrast, measures of central tendency describe a typical value (mean, median, mode), measures of position tell you where a single score sits within the distribution, and measures of correlation describe relationships between two variables. So the concept being tested is variability.