User Experience Meets GPS Trajectory Search

We investigate a user-centered approach to trajectory search in large data sets. We assume that user draws a query trajectory and expects to obtain a number of similar trajectories. Unlike the research results reported elsewhere, we try to answer the following simple question: What if we only focus on user experience of trajectory search, and give less or no importance to computational efficiency, how would we design such a user-centered trajectory search? Our answer is an approach based on gates through which a trajectory has to pass in order to be considered similar to the query trajectory. User thus does not have to draw an accurate query trajectory what can require a considerable amount of time, effort and attention to detail, and can lead to user frustration. We compare our approach to existing approaches, Geodabs and Geohash. For experimental evaluation we apply a dense synthetic data set. Our approach finds all trajectories that pass through any required gates, whereas Geodabs and Geohash only find a subset of similar trajectories with respect to a similarity measure.