Underlying Calculation for Standard Deviation Factors
Published: 28 Feb 2017
Last Modified Date: 02 Mar 2017
QuestionWhat is the underlying calculation tableau uses for standard deviation.
More specifically, what is the underlying calculation for the standard deviation factors in Tableau?
AnswerThe calculation Tableau Desktop is running for Standard Deviation is what every text book lists as the definition of standard deviation.
The -1/1 factor is AVG - 1*STDEV and AVG + 1*STDEV and the -2/2 factor is AVG - 2*STDEV and AVG + 2*STDEV.
Additional InformationThe attached workbook contains examples of calculating the -1/+1 manually using Table Calculation Functions.