In Perl or outside of Perl, is there a standard mathematical notation that can describe objects? I am hoping to use XML objects to train baysian networks (or should I say probabilistic trees?). I have read an article called object-orientated bayesian networks, this can be found with a google search. I think that this article offers a way of describing objects in a sensible way. I wonder if any Perl people have experience in using this kind of notation. And whether anyone here can offer guidance as to what standards should be conformed to.