80 likes | 212 Views
Geometric & Network Based Summarization. Atanu Roy Akash Agrawal. Problem Statement. Input A spatial network Set of activities and their locations Number of clusters ( k ) Output k sets of disjoint clustered activities (geometric and route based) Objective
E N D
Geometric & Network Based Summarization Atanu Roy AkashAgrawal
Problem Statement • Input • A spatial network • Set of activities and their locations • Number of clusters (k) • Output • k sets of disjoint clustered activities (geometric and route based) • Objective • Maximize the density and the coverage of the clusters • Constraint • Correct • ; where are the number of geometric and network based clusters
Motivation & Challenges • Motivation • Crime Detection and Prevention • Disaster Response • Challenges • K-means (P-median) & SNAS are NP_hard. [Reese2005, Unpublished] • Decision to use either of the solution is proven (in this work) to be an exponential problem.
Proposed Approach • Implement crimestat and KMR • Use each to have put k clusters on the network (total 2k). • Try eliminating k clusters one by one • Use coverage measure to eliminate geometric based cluster and density to eliminate network based ones.
Thank You • References • Dev Oliver, AbdussalamBannur, James M. Kang, ShashiShekhar, and Renee Bousselaire, A k-main routes approach to spatial network activity summarization: A summary of results, ICDM Workshops, 2010, pp. 265 - 272. • J. Reese (2006) Solution methods for the p-median problem: an annotated bibliography. Networks 48(3):125–142