In a many-to-one matching model with responsive preferences in which indifferences are allowed, we study three notions of core, three notions of stability, and their relationships. We show that (i) the core contains the stable set, (ii) the strong core coincides with the strongly stable set, and (iii) the super core coincides with the super stable set. We also show how the core and the strong core in markets with indifferences relate to the stable matchings of their associated tie-breaking strict markets.
Trabajo en conjunto con: Agustín G. Bonifacio (UNSL- IMASL, Argentina), P. Neme (UNSL- IMASL, Argentina), J. Oviedo (UNSL- IMASL, Argentina).