p2 (p1 , p3 ) p2p4 p5p3 p4 qp3 p1 p1 Mappings: LSH, random projections, minhashing Epsilon nets Works for small intrinsic dimension 10 / 26 3 Nearest Neighbors: Revising the Problem 11 / 26 Revision: Data Model interested in co-authors cited Scientist author cited Paper cited used words Several types of.