Abstract: How to quickly answer the question of the future location of a moving object is a fundamental problem for a variety of applications,such as ITS,location-aware advertisement,and moving objects monitoring.In this paper,we proposed an innovative AP-I (Adaptive Predictive-Index) which can efficiently answer predictive queries without any objects’ historical trajectories.Compared with existing Predictive Tree[4] index,our index can greatly reduce the overhead of index update by discovering and utilizing the co-relations among objects’ paths.Furthermore,by introducing AP (Adaptive Probability) and Pruning procedure,the size of AP-I is further reduced to improve the query performance.An extensive set of experiments have demonstrated that compared with Predictive Tree,our AP-I can not only achieve higheraccuracy,but also greatly improve the updating and space efficiency with the same query performance.

Key words: Predictive Query,Moving object,Algorithm optimization