Fixed Points of Many to Many matching
The Gale Shapley Algorithm (Deferred Acceptance Algorithm or DAA)
The DAA algorithm for one to one matching is a stable matching algorithm that is guaranteed to find a stable matching for any set of preferences.
While the one to one matching is well known, the many to many matching is not as well known.
The many to many matching is a generalization of the one to one matching, where each agent can be matched to multiple agents.
Code
Blair matching and DAA matching notebooks at:
https://github.com/FranciscoRMendes/matching-algorithms
Fixed Points of Many to Many matching
Define the rejection functions
recursive function on the underlying sets, like so
Example of iteration,
Claim : The fixed points of
Worked Out Example Many to Many DAA Matching
Workers
Firms
Step 1:
Step 2:
Step 3: