Description
Returns the
element-by-element
tail probability for an F-statistic,
where f is a real or double-precision matrix
with all its elements greater than 0,
dfn is an integer matrix
specifying the number of degrees of freedom in the numerator,
and dfd is an integer matrix specifying the number of degrees
of freedom in the denominator.
The tail probability for the F-statistic is
+infinity
/
| p(x, dfn, dfd) dx
/ f where p(x, n, d)
is the probability density function for an F-distribution with
n degrees of freedom in the numerator and
d degrees of freedom in the denominator.
Example
f = .1 : .1 : 10.
dfn = 5
dfd = 5
tail = ftail(f, dfn, dfd)
gtitle("Tail of F-statistic")
gplot(f, tail)
