What does standard deviation measure?

• A. Skewness
• B. The center tendency
• C. The spread or dispersion of values around the mean
• D. Kurtosis

Answer: (C)

Standard deviation measures how spread out the values are around the average. It captures variability: a small spread means most data are close to the mean, while a large spread means numbers are more dispersed. It’s calculated as the square root of the average squared deviations from the mean, which ties directly to dispersion rather than location. This differs from skewness (which looks at asymmetry of the shape) and kurtosis (which looks at how heavy the tails are). The center tendency tells you where the data cluster, but standard deviation tells you how tightly they cluster around that center. In practice, a smaller standard deviation indicates more consistency, while a larger one indicates more variability.