Rule of thumb · MathematicsNº 76 / 96

The mean is not the middle when data is skewed

A handful of extreme values can drag the average well away from where most of the data actually sits — the median, not the mean, is the more honest "typical value" for skewed distributions like income or home prices.

Why it works

Averages are pulled toward outliers because every value contributes proportionally to the sum — the median only cares about rank order, which is exactly why it resists a few extreme values that would distort the mean.

Do it exactly

Estimate with the rule, then check it against the calculator that models it properly.

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