Abstract
Given a finite set X of points in \(R^n\) and a family F of sets generated by the pairs of points of X, we determine volumetric and structural conditions for the sets that allow us to guarantee the existence of a positive-fraction subfamily \(F'\) of F for which the sets have non-empty intersection. This allows us to show the existence of weak epsilon-nets for these families. We also prove a topological variation of the existence of weak epsilon-nets for convex sets.
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Communicated by A. Constantin.
A. Magazinov was Supported by ERC Advanced Research Grant No. 267165 (DISCONV).
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Magazinov, A., Soberón, P. Positive-fraction intersection results and variations of weak epsilon-nets. Monatsh Math 183, 165–176 (2017). https://doi.org/10.1007/s00605-016-0892-2
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DOI: https://doi.org/10.1007/s00605-016-0892-2