Characterizing correlations of flow oscillations at bottlenecks
  "Oscillations" occur in quite different kinds of many-particle-systems when two groups of particles with different directions of motion meet or intersect at a certain spot. We present a model of pedestrian motion that is able to reproduce oscillations with different characteristics. The Wald-Wolfowitz test and Gillis' correlated random walk are shown to hold observables that can be used to characterize different kinds of oscillations. 
Tobias Kretz, Marko Woelki, and Michael Schreckenberg