Stability in a job market with linearly increasing valuations and quota system

We consider a job market in which preferences of players are represented by linearly increasing valuations. The set of players is divided into two disjoint subsets: a set of workers and a set of firms. The set of workers is further divided into subsets, which represent different categories or classes in everyday life. We consider that firms have vacant posts for all such categories. Each worker wants a job for a category to which he/she belongs. Firms have freedom to hire more than one worker from any category. A worker can work in only one category for at most one firm. We prove the existence of a stable outcome for such a market. The college admission problem by Gale and Shapley is a special case of our model.

Stability in a job market with linearly increasing valuations and quota system

We consider a job market in which preferences of players are represented by linearly increasing valuations. The set of players is divided into two disjoint subsets: a set of workers and a set of firms. The set of workers is further divided into subsets, which represent different categories or classes in everyday life. We consider that firms have vacant posts for all such categories. Each worker wants a job for a category to which he/she belongs. Firms have freedom to hire more than one worker from any category. A worker can work in only one category for at most one firm. We prove the existence of a stable outcome for such a market. The college admission problem by Gale and Shapley is a special case of our model.

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  • Proof
  • Consider the case when La= Ea=∅, for all a ∈ I . By Lemma3.7(i), pijdecreases for each
  • (i, j)∈ Ua\{La, Ea}, for all a ∈ I . However, p is discrete and pij≥ max{π,
  • βji} for each (i, j) ∈ Ua
  • αji} for each (i, j) ∈ U , a∈ I .
  • 0}, for all a ∈ I . However, p is discrete and pij
  • Therefore, pijcan be decreased only by a finite number of times.
  • Next we consider the case when La̸= ∅, or Ea̸= ∅. In either case, E reduces at Step 3. By Lemma
  • 0̸= ∅. In either case, E reduces at Step 3. By Lemma
  • 7(iv), in each iteration of the Job Allocation, E decreases or remains the same, and therefore this case is
  • possible at most|E| times. This completes the proof. ✷
  • Concluding remarks
  • We have presented a job market in which we have taken different categories of the workers into account. Each
  • firm employs worker according to its eligibility criteria. The preferences of players are represented by increasing
  • utility functions. Here we list some important points about the model and Job Allocation: 1. The existence of a pairwise stable outcome is guaranteed in our model. The salary in this model is a
  • discrete variable. The marriage model [6] and the Ali and Farooq model [1] are special cases of this
  • model. A possible extension of the model is to consider salary as a continuous variable.
  • By Lemma3.8, we have that p
  • is the maximum integer in [πij, πij] for which νji(−p) > ra, a∈ I , for j, a∈ I , for
  • some (i, j)∈ E . Since valuations are linearly increasing, the matching will be worker-optimal. It is possible
  • to define an algorithm by starting from the lowest possible salary and then increasing it accordingly. This
  • type of algorithm will yield firm-optimal stable outcomes.
  • The complexity of the Job Allocation is not polynomial as it depends on the length of [πij, πij] for each (i, j)∈ E .
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