Abstract
We define relations and their composition in a category with (E, M)-factorization structure, with M consisting of monomorphisms, but E not restricted to epimorphisms. We obtain an associativity criterion for composition of relations, and we study functional and induced relations. We show that under our assumptions, the categories of relations on functional and induced relations are isomorphic to the category of relations for the given category.
Similar content being viewed by others
References
Adámek, J., Herrlich, H. and Strecker, G. E.: Abstract and Concrete Categories, Wiley, New York, 1990.
Barr, M.: Relational algebras, in Reports of the Midwest Category Seminar IV, Lecture Notes in Math. 137, 1970, pp. 39–55.
Barr, M., Grillet, P. A. and van Osdol, D. H.: Exact Categories and Categories of Sheaves, Lecture Notes in Math. 236, 1971.
Bénabou, J.: Introduction to bicategories, in Reports of the Midwestern Category Seminar, Lecture Notes in Math. 47, 1967, pp. 1–77.
Fourman, M. P. and Scott, D. S.: Sheaves and logic, in Applications of Sheaves. Proceedings of the Durham Conference, Lecture Notes in Math. 753, 1979, pp. 302–401.
Freyd, P. J. and Kelly, G. M.: Categories of continuous functors I, J. Pure Appl. Algebra 2(1972), 169–191.
Goguen, J. A.: L-fuzzy sets, J. Math. Anal. Appl. 18(1967), 145–174.
Higgs, D.: A category approach to Boolean-valued set theory, Preprint, 1973.
Höhle, U. and Stout, L. N.: Foundations of fuzzy sets, Fuzzy Sets and Systems 40(1991), 257–296.
Jayewardene, R.: Relations and functional relations in categories, with examples from fuzzy set theory, Ph.D. Thesis, Carnegie Mellon University, 1995.
Kelly, G. M.: A note on relations relative to a factorization system, in Category Theory, Proceedings, Como 1990, Lecture Notes in Math. 1488, 1991, pp. 249–261.
Lawvere, F. W.: Metric spaces, generalized logic, and closed categories, Rend. Sem. Mat. Fis. Milano 43(1973), 135–166.
Klein, A.: Relations in categories, Illinois J. Math. 14(1970), 536–550.
Mac Lane, S.: An algebra of additive relations, Proc. Nat. Acad. Sci. U.S.A. 47(1963), 1043–1051.
Meisen, J.: On bicategories of relations and pullback spans, Comm. Algebra 1(1974), 377–401.
Monro, G. P.: Quasitopoi, logic and Heyting-valued models, J. Pure Appl. Algebra 42(1986), 141–164.
Pavlovi´c, D.:Maps I: Relative to a factorisation system, J. Pure Appl. Algebra 99(1995), 9–34.
Pavlovi´c, D.: Maps II: Chasing diagrams in categorical proof theory, J. of the IGPL 4(1996), 159–194.
Ponasse, D.: Categorical studies of fuzzy sets, Fuzzy Sets and Systems 28(1988), 235–244.
Puppe, D.: Korrespondenzen in abelschen Kategorien, Math. Ann. 148(1962), 1–30.
Stout, L. N.: The logic of unbalanced subobjects in a category with two closed structures, in Applications of Category Theory to Fuzzy Subsets, Kluwer Academic Publishers, Dordrecht, 1992, pp. 73–105.
Wyler, O.: Lecture Notes on Topoi and Quasitopoi,World Scientific Publishing Co., Singapore, 1991.
Wyler, O.: Fuzzy logic and categories of fuzzy sets, in Non-Classical Logics and Their Applications to Fuzzy Subsets, Kluwer Academic Publishers, Dordrecht, 1995, pp. 235–268.
Zadeh, L. A.: Fuzzy sets, Inform. and Control 8(1965), 338–353.
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Jayewardene, R., Wyler, O. Categories of Relations and Functional Relations. Applied Categorical Structures 8, 279–305 (2000). https://doi.org/10.1023/A:1008651524610
Issue Date:
DOI: https://doi.org/10.1023/A:1008651524610