NAME

Statistics::Distributions - Perl module for calculating critical values of common statistical distributions

SYNOPSIS

use Statistics::Distributions;

$chis=chisqrdistr (2,.05);
print "Chi-squared-crit (2 degrees of freedom, 95th percentile = 0.05 level) = $chis\n";
$u=udistr (.05);
print "u-crit (95th percentile = 0.05 level) = $u\n";
$t=tdistr (1,.005);
print "t-crit (1 degree of freedom, 99.5th percentile = 0.005 level) =$t\n";
$f=fdistr (1,3,.01);
print "F-crit (1 degree of freedom in numerator, 3 degrees of freedom in denominator, 99th percentile = 0.01 level) = $f\n";
$uprob=Statistics::Distributions::uprob (-0.85);
print "upper probability of the u distribution: Q(u) = 1-G(u) (u=1.43) = $uprob\n";

DESCRIPTION

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) distribution, which you will need to perfom a chi-squared test. 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. This module can also calculate the upper probability (5 significant digits) of the u (standard normal) distribution.

AUTHOR

Michael Kospach, mike.perl@gmx.at

SEE ALSO

Statistics::ChiSquare, Statistics::Table::t, Statistics::Table::F perl(1).