Four data sets used for the benchmark of HPDBSCAN.

Collection of geo-tagged Twitter data: This set has been collected and made available to us by Junjun Yin form the National Center for Supercomputing Application (NCSA). The dataset was obtained using the free twitter streaming API and contains exactly one percent of all geo-tagged of the United Kingdom in June 2014. It was initially created to investigate the possibility of mining peoples trajectories and to identify hotspots and points of interest (clusters of people) through monitoring tweet density. The full collections spans roughly 16.6 million tweets. A smaller subset of this was generated by filtering the entire set for the first week of June only.

Oldtown of Bremen point cloud

This data has been collected and made available by Dorit Borrmann and Andreas Nüchter from the Institute of Computer Science at the Jacobs University Bremen, Germany. It is a 3D point cloud of the oldtown of Bremen, Germany. A point cloud is a set of points and its represening coordinate system that often model the surface of objects. This particular point cloud of Bremen was recorded using a laser scanner system mounted onto an autonomous robotic vehicle. It has stopped at 11 different locations, performing each time a full 360° scan of the surrounding area. Given the GPS triangulized position and perspective of the camera the sub-point clouds where combined to one monolithic.