Uncertainty in Spatial Trajectories Goce Trajcevski

Uncertainty Throughout History Chapter outline Introduction Uncertainty Throughout History Uncertainty in Spatial and Temporal Database Modeling Uncertain Trajectories Processing Spatio-Temporal Queries for Uncertain Trajectories Summary Balance breadth and depth

Uncertainty Throughout History Philosophy and Logic Epistemic Logic (BaP) Modal Logic (,) Possible Worlds Uncertainty in AI and Databases Model-Theoretic issues (Possible Models) NULLs (open vs. closed world assumption) Probabilistic databases (and possible worlds) Time Geography and Inexact Geometries Uncertain location over time Re-evaluation of Euclidian postulates

Uncertain in Spatial and Temporal Databases Spatial Databases Imprecise Locations Impact on Queries Temporal Databases Valid Time Transaction time Constructs (T-SQL)

Modeling Uncertain Trajectories Location Uncertainty Models Various Sources’ Imprecision (GPS; Sensors) Quest for data reduction

Modeling Uncertain Trajectories Cones, Beads, Necklaces

Modeling Uncertain Trajectories Sheared Cylinders

Modeling Uncertain Trajectories Uncertainty on Road Networks

Processing Spatio-Temporal Queries for Uncertain Trajectories Query Categories Range NN Few others in “potpourri” Capturing the impact (of the uncertainty model) into the syntax of the query Discuss a few processing algorithms “Potpourri” Other predicates/issues

Processing Spatio-Temporal Queries for Uncertain Trajectories

Processing Spatio-Temporal Queries for Uncertain Trajectories

Processing Spatio-Temporal Queries for Uncertain Trajectories NN-query for crisp object and uncertain-rest (cone model)

Processing Spatio-Temporal Queries for Uncertain Trajectories “Messing” the context

Processing Spatio-Temporal Queries for Uncertain Trajectories Potpourri: Alibi query Topological Predicates Inside-ness; Along-ness; Touching; Communication savings V-to-server WSN