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The Excel F.DIST Function
Basic Description
The Excel F.DIST function calculates the Probability Density Function or the Cumulative Distribution Function
for the F Distribution. This function is frequently used used to measure the degree of diversity between two
data sets.
The function is new to Excel 2010 and so is not available in earlier versions of Excel.
The format of the function is :
F.DIST( x, deg_freedom1, deg_freedom2, cumulative )
Where the function arguments are:
| x |
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The (positive) numeric value at which the function is to be evaluated
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| deg_freedom1 |
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An integer specifying the numerator degrees of freedom
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| deg_freedom2 |
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An integer specifying the denominator degrees of freedom
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| cumulative |
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A logical argument that specifies the type of F Distribution to be calculated. This can be either:
| TRUE | - |
use the cumulative distribution function |
| FALSE | - |
use the probability density function |
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If either deg_freedom1 or deg_freedom2 are decimal numbers, these are truncated to integers by Excel.
F.Dist Function Examples
Example 1 - Probability Density Function
The chart on the right shows the probability density function for the F Distribution with the numerator degrees
of freedom equal to 2 and the denominator degrees of freedom equal to 5.
If you want to use Excel to calculate the value of this function at x = 1, this can be done by
the F.Dist function, as follows:
=F.DIST( 1, 2, 5, FALSE )
This gives the result 0.308000822.
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F Prob. Distribution with deg_freedom1 = 2 & deg_freedom2 = 5
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Example 2 - Cumulative Distribution Function
The chart on the right shows the Cumulative F Distribution function with the numerator degrees
of freedom equal to 2 and the denominator degrees of freedom equal to 5.
If you want to use Excel to calculate the value of this function at x = 1, this can be done by
the F.Dist function, as follows:
=F.DIST( 1, 2, 5, TRUE )
This gives the result 0.56879885.
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Cumulative F Distrib. with deg_freedom1 = 2 & deg_freedom2 = 5
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Further information and examples of the Excel F.Dist function can be found on the
Microsoft Office website.
Trouble Shooting
If you get an error from the Excel F.Dist function this is likely to be one of the following :
Common Errors
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#NUM!
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Occurs if either:
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the supplied x value is < 0 |
| or | |
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either the supplied deg_freedom1 or the supplied deg_freedom2 argument is < 1 |
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#VALUE!
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Occurs if any of the x, deg_freedom1 or deg_freedom2 arguments are non-numeric
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