05-30-2008, 05:08 PM
bzptc0 Wrote:I have another question on the flashcards - I've attached the document, but in a nutshell, the question is - are there more than one SD formula?>>
:confused:
I see where you got confused because I got stuck at the exact same place!! (I even posted about it!) You only do the n-1 when your SD is for a sample (as opposed to a population).
Does your calculator do this for you? Mine does, I just have to enter the data set, and then select which key I want depending on if I want it to calculate SD of a sample or SD of a population. Check your calculator, it can make your life easy. I worked out like 40 of these long hand before I found my magic button

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