The standard deviation of a set of lotto numbers is the square root of its variance. It shows how much variation there is from the "average" (mean). This mathematical calculation is one of the first in every statistics book. When applied to lottery combinations, it sorts combinations by how much the numbers in the combination vary from the average of those numbers. Numbers with the lowest and highest Standard Deviation are rare while combinations with mid value scores are much more common. Standard deviations form a very clear bell curve that is much narrower than the bell curve of the sums. Typical scores range from about 3 to about 26. Standard deviation is displayed in our SLHEdit program. You can use this information to your advantage using the Standard Deviation filter that is available in Filtering Full Wheel Generator.

Also see: FAQ322: How is the standard deviation calculated in SLHEdit.