Which concept describes the extent to which individual data values depart from the mean?

• A. Measures of dispersion
• B. Measures of central tendency
• C. Normal distribution curve
• D. Outlier analysis

Answer: (A)

Dispersion measures describe how spread out data are around the mean. This concept quantifies how far individual data values tend to deviate from the central value, typically the mean. The standard deviation is the most common way to express this—it's the average distance of data points from the mean, so larger values mean more variability. Variance is that distance squared, while other descriptors like the range or interquartile range give quick senses of spread in different ways.

In practice, understanding dispersion helps gauge how reliable the mean is as a representative value—narrow dispersion means most values are close to the mean, while wide dispersion indicates more variation among observations.

The other terms describe related ideas but not the general measure of how far data values depart from the mean. Central tendency focuses on where data cluster (the mean, median, or mode). The normal distribution curve describes the overall shape of the data, not the specific degree of departure from the mean. Outlier analysis looks at unusually far values rather than the typical spread of all values.