use Statistics::Basic qw(:all);

my $median = median( 1,2,3 );
my $mean   = mean(  [1,2,3]); # array refs are ok too

my $variance = variance( 1,2,3 );
my $stddev   = stddev(   1,2,3 );

my $correlation = correlation( [1 .. 3], [1 .. 3] );