  We present an interactive visualisation tool for recommending travel
trajectories. This system is based on new machine learning formulations and
algorithms for the sequence recommendation problem. The system starts from a
map-based overview, taking an interactive query as starting point. It then
breaks down contributions from different geographical and user behavior
features, and those from individual points-of-interest versus pairs of
consecutive points on a route. The system also supports detailed quantitative
interrogation by comparing a large number of features for multiple points.
Effective trajectory visualisations can potentially benefit a large cohort of
online map users and assist their decision-making. More broadly, the design of
this system can inform visualisations of other structured prediction tasks,
such as for sequences or trees.
