The standard deviation is a number that measures how far data values are from their mean.

The most common measure of variation, or spread, is the standard deviation. In some data sets, the data values are concentrated closely near the mean in other data sets, the data values are more widely spread out from the mean. Recognize, describe, and calculate the measures of the spread of data: variance, standard deviation, and range.Īn important characteristic of any set of data is the variation in the data.