Approximation Algorithms for Outlier Removal in Convex Hulls
نویسندگان
چکیده
Given n points in R, we give approximation algorithms to find a subset of k of the points that has minimum-area or minimum-perimeter convex hull. We give algorithms that individually yield constantfactor approximations to the minimum-perimeter problem with different running times for differing values of k. Together, these algorithms provide a constant-factor approximation of the minimumperimeter problem in linear time. We also show a 2-approximation for the minimum-area problem in sub-cubic time, as well as an analysis of a collection of heuristics that work well in practice.
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تاریخ انتشار 2012