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تسجيل مستخدم جديدFurther Results on Stability-Preserving Mechanisms for School Choice
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We build on the stability-preserving school choice model introduced and studied recently in [MV18]. We settle several of their open problems and we define and solve a couple of new ones.
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We address the following dynamic version of the school choice question: a city, named City, admits students in two temporally-separated rounds, denoted $mathcal{R}_1$ and $mathcal{R}_2$. In round $mathcal{R}_1$, the capacity of each school is fixed a
nd mechanism $mathcal{M}_1$ finds a student optimal stable matching. In round $mathcal{R}_2$, certain parameters change, e.g., new students move into the City or the City is happy to allocate extra seats to specific schools. We study a number of Settings of this kind and give polynomial time algorithms for obtaining a stable matching for the new situations. It is well established that switching the school of a student midway, unsynchronized with her classmates, can cause traumatic effects. This fact guides us to two types of results, the first simply disallows any re-allocations in round $mathcal{R}_2$, and the second asks for a stable matching that minimizes the number of re-allocations. For the latter, we prove that the stable matchings which minimize the number of re-allocations form a sublattice of the lattice of stable matchings. Observations about incentive compatibility are woven into these results. We also give a third type of results, namely proofs of NP-hardness for a mechanism for round $mathcal{R}_2$ under certain settings.
We study social choice mechanisms in an implicit utilitarian framework with a metric constraint, where the goal is to minimize textit{Distortion}, the worst case social cost of an ordinal mechanism relative to underlying cardinal utilities. We consid
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In large scale collective decision making, social choice is a normative study of how one ought to design a protocol for reaching consensus. However, in instances where the underlying decision space is too large or complex for ordinal voting, standard
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