Algebraic Methods for Studying Interactions Between Epidemiological Variables F. Ricceri, C. Fassino, G. Matullo, M. Roggero, M.-L. Torrente, P. Vineis and L. Terracini Math. Model. Nat. Phenom., 7 3 (2012) 227-252 Published online: 06 June 2012 DOI: 10.1051/mmnp/20127314