FTEST

FTEST(array1, array2)

Returns the probability value from an f distribution.

array1	The first array.
array2	The second array.

REMARKS

* This function is only available for backwards compatibility and should not be used.
* F.TEST was added in Excel 2010 to replace this function.
* An F-test returns the one-tailed probability that the variances in two arrays are not significantly different.
* The arguments must be either numbers or names, arrays, or cell references that contain numbers.
* If an array or reference argument contains text, logical values, or empty cells, those values are ignored; however, cells with the value zero are included.
* If the number of data points in array1 or array2 is less than 2, or if the variance of array1 or array2 is zero, then #DIV/0! is returned.
* This function claims to return the probability for the F-value in a one tailed test for the null hypothesis that the variances of two samples are equal. This actually returns the result for a two-tailed test.
* This function can be used to determine whether two samples have different variances.
* This is similar to the CHITEST, TTEST and ZTEST functions.
* For the Microsoft documentation refer to support.microsoft.com
* For the Google documentation refer to support.google.com

	A
1	=FTEST({1, 2, 3}, {4, 5, 6}) = 1
2	=FTEST({6, 7, 9, 15, 21}, {20, 28, 31, 38, 40}) = 0.648