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tja26
01-18-2006, 10:04 AM
I have a data set and I want to know whether it is Normally distributed or not. How can I do this easily? I would prefer to be able to do it in Excel as I don't have any advanced statistical packages like SPSS.

Thanks for your help

Tim

JohnM
01-18-2006, 10:57 AM
The following link is a pdf document that discusses how to construct a normal probability plot in Excel.

http://www.decisionsciences.org/decisionline/Vol29/29_1/class_29_1.pdf

Just keep in mind that you can't "prove" or say "yes" or "no" if the question is asked: "Is the data normally distributed?"

What you can say is whether or not there is enough evidence, either visually or through a test, to say that the sample data "probably did not" come from a normally distributed population.

You might also consider a relatively inexpensive Excel add-on like Analyse-It (http://www.analyse-it.com/) that can do some simple procedures, such as tests for normality.

tja26
01-22-2006, 04:19 PM
That's perfect, thank you very much for your help