Popular branchings and their dual certificates
نویسندگان
چکیده
Abstract Let G be a digraph where every node has preferences over its incoming edges. The of extend naturally to branchings , i.e., directed forests; branching B is popular if does not lose head-to-head election (where nodes cast votes) against any branching. Such have natural application in liquid democracy. problem decide admits or not. We give characterization terms dual certificates and use this design an efficient combinatorial algorithm for the problem. When are weak rankings, we our formulate polytope original space also show that can modified compute with least unpopularity margin . strict “approximately popular” always exist.
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ژورنال
عنوان ژورنال: Mathematical Programming
سال: 2021
ISSN: ['0025-5610', '1436-4646']
DOI: https://doi.org/10.1007/s10107-021-01659-6