The stupid question is the question not asked  
PerlMonks 
Re^3: 3D Planar Multiple Linear Regression?by SimonClinch (Chaplain) 
on May 16, 2011 at 15:35 UTC ( #905106=note: print w/ replies, xml )  Need Help?? 
I have to admit the documentation doesn't tell you how to do what the module claims. Statistics::LineFit, on the other hand, does have the least squares methods required to extend a line of regression analysis into 3D, provided you can cope with the required matrix iterations, see http://www.weibull.com/DOEWeb/estimating_regression_models_using_least_squares.htm One world, one people
In Section
Seekers of Perl Wisdom

