Abstract: In many packetized communication networks, it is not feasible to obtain exact counts of traffic (OD counts) between specific origin-destination node pairs, because the link counts that are readily obtainable at router interfaces are aggregated indiscriminately over OD pairs. The best that can be done is to make a probabilistic inference concerning the OD counts from the observed link counts. Such an inference relies upon a known linear relationship between observed link counts and unknown OD counts, and a statistical model describing how the values of the OD and link counts are probabilistically distributed. Disclosed is an improved method for making such inferences. The disclosed method takes explicit account of past data when forming a current estimate of the OD counts. As a consequence, behavior that evolves in time is described with improved accuracy and smoothness.