For some reason, I immediately thought of an old book I read called "Laws of Form". It has quite a following, check it out at LawsofForm

Basically it sets up a mathematics for setting distinctions around sets of data, and manipulating them. When I first read it, I realized that humans don't see the world in it's correct spatial depth. We look toward "outer space" for answers, where the "deeper space" is down in the miniscule. Anyways, it may be applicable to your equation's problem. It would definitely give you some clues on how to approach your modelling.