Computing longest duration flocks in trajectory data
Moving point object data can be analyzed through the dis- covery of patterns. We consider the computational e±ciency of computing two of the most basic spatio-temporal pat- terns in trajectories, namely °ocks and meetings. The pat- terns are large enough subgroups of the moving point objects that exhibit similar movement and proximity for a certain amount of time. We consider the problem of computing a longest duration °ock or meeting. We give several exact and approximation algorithms, and also show that some variants are as hard as MaxClique to compute and approximate.