2020/11/26 by Adiel Statman, Statman, Adiel, Liat Rozenberg +3
Computer Science · #Data Structures and Algorithms (cs.DS) #FOS: Computer and information sciences #cs.DS
paper · pdf · doi:10.48550/arxiv.2011.13476
arxiv created 2020/11/26 · arxiv updated 2020/11/30
In projective clustering we are given a set of n points in Rd and wish to cluster them to a set S of k linear subspaces in Rd according to some given distance function. An \eps-coreset for this problem is a weighted (scaled) subset of the input points such that for every such possible S the sum of these distances is approximated up to a factor of (1+\eps). We suggest to reduce the size of existing coresets by suggesting the first O(log(m)) approximation for the case of m lines clustering in O(ndm) time, compared to the existing exp(m) solution. We then project the points on these lines and prove that for a sufficiently large m we obtain a coreset for projective clustering. Our algorithm also generalize to handle outliers. Experimental results and open code are also provided.