Characteristic properties of equivalent structures in compositional models

Compositional model theory serves as an alternative approach to multidimensional probability distribution representation and processing. Every compositional model over a finite non-empty set of variables N is uniquely defined by its generating sequence – an ordered set of low-dimensional probability distributions. A generating sequence structure induces a system of conditional independence statements over N valid for every multidimensional distribution represented by a compositional model with this structure. The equivalence problem is how to characterise whether all independence statements induced by structure P are induced by a second structure P and vice versa. This problem can be solved in several ways. A partial solution of the so-called direct characterisation of an equivalence problem is represented here. We deduce and describe three properties of equivalent structures invariant in a class of equivalent structures. We call them characteristic properties of equivalence.