Efficient algorithms for finding optimal meeting point on road networks

Given a set of points Q on a road network, an optimal meeting point (OMP) query returns the point on a road network G = (V, E) with the smallest sum of network distances to all the points in Q. This problem has many real world applications, such as minimizing the total travel cost for a group of people who want to find a location for gathering. While this problem has been well studied in the Euclidean space, the recently proposed state-of-the-art algorithm for solving this problem in the context of road networks is still not efficient. In this paper, we propose a new baseline algorithm for the OMP query, which reduces the search space from |Q| · |E| to |V| + |Q|. We also present two effective pruning techniques that further accelerate the baseline algorithm. Finally, in order to support spatial applications that involve large flow of queries and require fast response, an extremely efficient algorithm is proposed to find a high-quality near-optimal meeting point, which is orders of magnitude faster than the exact OMP algorithms. Extensive experiments are conducted to verify the efficiency of our algorithms.