Normal Distribution


Posted by Dave on October 17, 2001 6:00 AM

I have a population of 660 items. The range of values is from 1 to 30.

How can I generate a data series that will give me a chart depicting a normal distribution bell curve?

I would prefer to do this without macros if possible.



Posted by Don C on October 17, 2001 11:14 AM

In column A, create a series from 1 to 99 (the curve will have 99 data points)
In column B, enter area values using the NORMDIST function. In B2 (first data point) enter,

=NORMDIST(A2,50,21.06,0)
and copy down to point 99. This will give you a mean of 50 and a standard deviation of 21.06 (you will want to change this to meet your specific situation). Check the help file for the cumulative function (the final zero).

This table plots a nice curve of the Normal Curve Equivalent distribution. Remember that the normal curve is a family of curves with varying standard deviations, so you will want to use the appropriate value for your data set.