Microsoft Office Tutorials and References
In Depth Information
Working with Normal Distributions
In statistics, a common topic is the normal distribution, also known as a bell curve. Excel has several functions
designed to work with normal distributions. This is not a statistics book, so I assume that if you're reading this
section, you're familiar with the concept.
The examples in this section are available at this book's website. The filename is nor-
Figure 10-6 shows a workbook that contains formulas that generate the two charts: a normal distribution and a
cumulative normal distribution. The formulas use the values entered into cell B1 (name Mean ) and cell B2
(named SD , for standard deviation ). The values calculated cover the mean plus/minus three standard deviations.
Column A contains formulas that generate 25 equally spaced intervals, ranging from –3 standard deviations to
+3 standard deviations.
A normal distribution with a mean of 0 and a standard deviation of 1 is known as the “standard normal distribu-
tion.” The worksheet is set up to work with any mean and any standard deviation.
Formulas in column B calculate the height of the normal curve for each of the 25 values in column A. Cell B5
contains this formula, which is copied down the column: