{"publication_status":"published","date_updated":"2021-01-12T08:16:22Z","has_accepted_license":"1","alternative_title":["LIPIcs"],"_id":"7989","day":"01","user_id":"2DF688A6-F248-11E8-B48F-1D18A9856A87","quality_controlled":"1","month":"06","article_number":"61:1-61:13","file":[{"relation":"main_file","file_id":"8005","checksum":"d0996ca5f6eb32ce955ce782b4f2afbe","date_created":"2020-06-23T06:56:23Z","date_updated":"2020-07-14T12:48:06Z","access_level":"open_access","file_size":645421,"file_name":"2020_LIPIcsSoCG_Patakova_61.pdf","content_type":"application/pdf","creator":"dernst"}],"file_date_updated":"2020-07-14T12:48:06Z","tmp":{"short":"CC BY (4.0)","image":"/images/cc_by.png","legal_code_url":"https://creativecommons.org/licenses/by/4.0/legalcode","name":"Creative Commons Attribution 4.0 International Public License (CC-BY 4.0)"},"language":[{"iso":"eng"}],"oa_version":"Published Version","status":"public","scopus_import":"1","ddc":["510"],"year":"2020","citation":{"short":"Z. Patakova, in:, 36th International Symposium on Computational Geometry, Schloss Dagstuhl - Leibniz-Zentrum für Informatik, 2020.","ieee":"Z. Patakova, “Bounding radon number via Betti numbers,” in 36th International Symposium on Computational Geometry, Zürich, Switzerland, 2020, vol. 164.","mla":"Patakova, Zuzana. “Bounding Radon Number via Betti Numbers.” 36th International Symposium on Computational Geometry, vol. 164, 61:1-61:13, Schloss Dagstuhl - Leibniz-Zentrum für Informatik, 2020, doi:10.4230/LIPIcs.SoCG.2020.61.","chicago":"Patakova, Zuzana. “Bounding Radon Number via Betti Numbers.” In 36th International Symposium on Computational Geometry, Vol. 164. Schloss Dagstuhl - Leibniz-Zentrum für Informatik, 2020. https://doi.org/10.4230/LIPIcs.SoCG.2020.61.","ista":"Patakova Z. 2020. Bounding radon number via Betti numbers. 36th International Symposium on Computational Geometry. SoCG: Symposium on Computational Geometry, LIPIcs, vol. 164, 61:1-61:13.","ama":"Patakova Z. Bounding radon number via Betti numbers. In: 36th International Symposium on Computational Geometry. Vol 164. Schloss Dagstuhl - Leibniz-Zentrum für Informatik; 2020. doi:10.4230/LIPIcs.SoCG.2020.61","apa":"Patakova, Z. (2020). Bounding radon number via Betti numbers. In 36th International Symposium on Computational Geometry (Vol. 164). Zürich, Switzerland: Schloss Dagstuhl - Leibniz-Zentrum für Informatik. https://doi.org/10.4230/LIPIcs.SoCG.2020.61"},"date_published":"2020-06-01T00:00:00Z","volume":164,"publication":"36th International Symposium on Computational Geometry","type":"conference","publication_identifier":{"isbn":["9783959771436"],"issn":["18688969"]},"date_created":"2020-06-22T09:14:18Z","abstract":[{"text":"We prove general topological Radon-type theorems for sets in ℝ^d, smooth real manifolds or finite dimensional simplicial complexes. Combined with a recent result of Holmsen and Lee, it gives fractional Helly theorem, and consequently the existence of weak ε-nets as well as a (p,q)-theorem. More precisely: Let X be either ℝ^d, smooth real d-manifold, or a finite d-dimensional simplicial complex. Then if F is a finite, intersection-closed family of sets in X such that the ith reduced Betti number (with ℤ₂ coefficients) of any set in F is at most b for every non-negative integer i less or equal to k, then the Radon number of F is bounded in terms of b and X. Here k is the smallest integer larger or equal to d/2 - 1 if X = ℝ^d; k=d-1 if X is a smooth real d-manifold and not a surface, k=0 if X is a surface and k=d if X is a d-dimensional simplicial complex. Using the recent result of the author and Kalai, we manage to prove the following optimal bound on fractional Helly number for families of open sets in a surface: Let F be a finite family of open sets in a surface S such that the intersection of any subfamily of F is either empty, or path-connected. Then the fractional Helly number of F is at most three. This also settles a conjecture of Holmsen, Kim, and Lee about an existence of a (p,q)-theorem for open subsets of a surface.","lang":"eng"}],"oa":1,"author":[{"id":"48B57058-F248-11E8-B48F-1D18A9856A87","first_name":"Zuzana","last_name":"Patakova","full_name":"Patakova, Zuzana","orcid":"0000-0002-3975-1683"}],"publisher":"Schloss Dagstuhl - Leibniz-Zentrum für Informatik","intvolume":" 164","department":[{"_id":"UlWa"}],"article_processing_charge":"No","external_id":{"arxiv":["1908.01677"]},"doi":"10.4230/LIPIcs.SoCG.2020.61","title":"Bounding radon number via Betti numbers","conference":{"start_date":"2020-06-22","name":"SoCG: Symposium on Computational Geometry","location":"Zürich, Switzerland","end_date":"2020-06-26"}}