T
T Dutton
Does Excel STDEV calculate in 3 stdev?
I wish Microsoft would do away with the STDEVP function. It has no use. The difference is that STDEV divides by n-1 and STDEVP divides by n. Can anyone tell me when you would use STDEVP?In Excel STDEV yeilds one sample standard deviation. To get 3 sigma you need to multiply it by 3. Also, if you need the standard deviation of a population, you should use STDEVP instead.
Can anyone tell me when you would use STDEVP?
I wish Microsoft would do away with the STDEVP function. It has no use. The difference is that STDEV divides by n-1 and STDEVP divides by n. Can anyone tell me when you would use STDEVP?
Actually S^2 is the MLE for sigma squared...but that is not the point. If as Wes stated, you have the entire population, then why would you need to know the standard deviation. That is to say, any inferences to be made can be made from the data in the population. There are no confidence intervals that need to be calculated. I am stumped, regardless of the theoretical differences between sigma and S, why there is an application that someone would be using Excel for that requires the population stdev.
Each measurement is a useful summary of the data. The mean doesn't tell you what each value is, but it does tell you roughly what to expect. Similarly, the standard deviation doesn't tell you how far each value is from the mean, but it does tell you roughly what to expect. No summary is as complete as the full data set, but this two number summary is pretty good to describe the main features of a set of data.