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arXiv · 1205.4378

Inferring Taxi Status Using GPS Trajectories

Yin Zhu·Yu Zheng·Liuhang Zhang·Darshan Santani·Xing Xie·Qiang Yang
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Abstract

In this paper, we infer the statuses of a taxi, consisting of occupied, non-occupied and parked, in terms of its GPS trajectory. The status information can enable urban computing for improving a city's transportation systems and land use planning. In our solution, we first identify and extract a set of effective features incorporating the knowledge of a single trajectory, historical trajectories and geographic data like road network. Second, a parking status detection algorithm is devised to find parking places (from a given trajectory), dividing a trajectory into segments (i.e., sub-trajectories). Third, we propose a two-phase inference model to learn the status (occupied or non-occupied) of each point from a taxi segment. This model first uses the identified features to train a local probabilistic classifier and then carries out a Hidden Semi-Markov Model (HSMM) for globally considering long term travel patterns. We evaluated our method with a large-scale real-world trajectory dataset generated by 600 taxis, showing the advantages of our method over baselines.

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Yin Zhu, Yu Zheng, Liuhang Zhang, Darshan Santani, Xing Xie, Qiang Yang. 2012-05-20. Inferring Taxi Status Using GPS Trajectories. https://arxiv.org/abs/1205.4378

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