Vexing terminology question

[eve_prime]

I'm looking for a word or phrase to describe a model. Suppose we have a trait "T" that we want to understand better, and we create a model that shows that at a low level of a trait, certain phenomena (such as "a" and "b") are associated with it, and at a high level, different phenomena are associated with it (such as "z"). I'm looking for a word that I can use to describe the relationship between a, b, z, and T. One thing I could say is that I can rank-order a, b, and z in terms of their relationship with T, producing a "model that displays rank-ordering of factors associated with a continous variable." That's clunkier than I'd like, and I'd prefer a simple phrase gets the whole gist of it. However, "hierarchical model" is not the phrase I want, even though z implies higher levels of T than a or b, because "hierarchical model" is already used to refer to a model of nested class relationships.

Does anyone know what it is I'm trying to say? :)