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Dynamic task assignment in spatial crowdsourcing

Spatial crowdsourcing is a crowdsourcing paradigm featured with spatiotemporal information of tasks and workers. It has been widely adopted in mobile computing applications and urban services such as citizen sensing, P2P ride-sharing and Online-To-Offline services. One fundamental and unique issue in spatial crowdsourcing is dynamic task assignment (DTA), where tasks and workers appear dynamically and need to be assigned under spatiotemporal constraints. In this paper, we aim to provide a brief overview on the basics and frontiers of DTA research. We define the generic DTA problem and introduce the evaluation metrics to its solutions. Then we review mainstream solutions to the DTA problem. Finally we point out open questions and opportunities in DTA research.