  Taxi drivers often take much time to navigate the streets to look for
passengers, which leads to high vacancy rates and wasted resources. Empty taxi
cruising remains a big concern for taxi companies. Analyzing the pick-up point
selection behavior can solve this problem effectively, providing suggestions
for taxi management and dispatch. Many studies have been devoted to analyzing
and recommending hot-spot regions of pick-up points, which can make it easier
for drivers to pick up passengers. However, the selection of pick-up points is
complex and affected by multiple factors, such as convenience and traffic
management. Most existing approaches cannot produce satisfactory results in
real-world applications because of the changing travel demands and the lack of
interpretability. In this paper, we introduce a visual analytics system,
T-PickSeer, for taxi company analysts to better explore and understand the
pick-up point selection behavior of passengers. We explore massive taxi GPS
data and employ an overview-to-detail approach to enable effective analysis of
pick-up point selection. Our system provides coordinated views to compare
different regularities and characteristics in different regions. Also, our
system assists in identifying potential pick-up points and checking the
performance of each pick-up point. Three case studies based on a real-world
dataset and interviews with experts have demonstrated the effectiveness of our
system.
