Standard deviation measures how spread out numbers are around their mean.
Why it matters
A small value means data cluster near the mean. Use the population formula for a whole group and the sample formula (dividing by n minus 1) for a subset.
Standard deviation measures how spread out numbers are around their mean.
A small value means data cluster near the mean. Use the population formula for a whole group and the sample formula (dividing by n minus 1) for a subset.