Finding frequent entities in continuous data

Ferran Alet, Rohan Chitnis, Leslie P. Kaelbling, Tomas Lozano-Perez

CSAIL, Massachusetts Institute of Technology, Chambridge, MA.

Abstact In many applications that involve processing high-dimensional data, it is important to identify a small set of entities that account for a significant fraction of detections. Rather than formalize this as a clustering problem, in which all detections must be grouped into hard or soft categories, we formalize it as an instance of the frequent items or heavy hitters problem, which finds groups of tightly clustered objects that have a high density in the feature space. We show that the heavy hitters formulation generates solutions that are more accurate and effective than the clustering formulation. In addition, we present a novel online algorithm for heavy hitters, called HAC, which addresses problems in continuous space, and demonstrate its effectiveness on real video and household domains.

Household dataset

Raw Dataset Videos: Camera 1 Camera 2 Camera 3 Camera 4

Object queries

Proofs of Theorems cited in the paper

Link to proofs