This Perl module calulates percentage points (5 significant digits) of
the u (standard normal) distribution, the student's t distribution, the
chi-square distribution and the F distribution. It can also calculate
the upper probability (5 significant digits) of the u (standard normal),
the chi-square, the t and the F distribution.  These critical values are
needed to perform statistical tests, like the u test, the t test, the F
test and the chi-squared test, and to calculate confidence intervals.

-Anton
<tobez@FreeBSD.org>