Practically: Weighted Standard deviation for non statisticians
This article will discuss how to find weighted standard deviation of groups while there is no data about the individuals inside the groups. Sometimes we have partial information about averages values and groups with weight of the group but how can we find out the standard deviation of the whole groups without the measurements of each individual? a suggestion, verification and practical example will be shown.
Steps to reproduce
a. Gather data. b. Divide into groups. c. Calculate StDev, Average, Weghted Average. d. Use the fomula. e. Verify that the formula output of Weighted standard StDev matches the StDev of all the groups.