In this paper we propose and study the problem of trajectory-driven influential billboard placement: given a set of billboards U (each with a location and a cost), a database of trajectories T and a budget L, find a set of billboards within the budget to influence the largest number of trajectories. One core challenge is to identify and reduce the overlap of the influence from different billboards to the same trajectories, while keeping the budget constraint into consideration. We show that this problem is NP-hard and present an enumeration based algorithm with (1 − 1/e) approximation ratio. However, the enumeration-based method is costly when |U | is large. By exploiting the locality property of billboards' influence, we propose a partitionbased framework PartSel. PartSel partitions U into a set of small clusters, computes the locally influential billboards for each cluster, and merges them to generate the global solution. Since the local solutions can be obtained much more efficient than the global one, PartSel can reduce the computation cost greatly; meanwhile it achieves a non-trivial approximation ratio guarantee. Then we propose a LazyProbe method to further prune billboards with low marginal influence, while achieving the same approximation ratio as PartSel. Experiments on real datasets verify the efficiency and effectiveness of our methods.
And the work in REF propose and study the problem of trajectory-driven influential billboard placement.
Trajectory-driven Influential Billboard Placement
Proceedings of the 24th ACM SIGKDD International Conference on Knowledge Discovery & Data Mining
Computer Science