Choice Functions

Ron Aharoni; Joseph Briggs

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arXiv · 2107.12881

Choice Functions

Ron Aharoni·Joseph Briggs

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Abstract

This is a survey paper on rainbow sets (another name for ``choice functions''). The main theme is the distinction between two types of choice functions: those having a large (in the sense of belonging to some specified filter, namely closed up set of sets) image, and those that have a large domain and small image, where ``smallness'' means belonging to some specified complex (a closed-down set). The paper contains some new results: (1) theorems on scrambled versions, in which the sets are re-shuffled before choosing the rainbow set, and (2) results on weighted and cooperative versions - to be defined below.

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BibTeX RIS

Ron Aharoni, Joseph Briggs. 2021-07-27. Choice Functions. https://arxiv.org/abs/2107.12881

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