1. A computer implemented method for modeling movement of objects in an environment, comprising: detecting discrete events caused by objects moving in an environment with a set of sensors arranged at known locations in the environment; linking sequences of temporally and spatially adjacent discrete events to form a set of tracklets; constructing a set of directed graphs from the set of tracklets, the graphs including at least one starting node, at least one terminating node, and one or more intermediate nodes where multiple tracklets connect giving rise to ambiguities in the movement of the objects; and assigning probabilities to the nodes, the probabilities indicating likelihoods that the objects were at particular known locations to model the movement of the objects in the environment.