Stability analysis of activity-based models: Case study of the Tel Aviv transportation model

The Tel Aviv activity based model structure is similar to other activity based models described in the literature. The model run is supposed to converge to the equilibrium between generated tours and corresponding level of service (LOS) data. However, individual tour generation uses random draws for various choices (activity, time of day, destination, and mode). This introduces simulation errors, which combined with population sampling and limited precision of static traffic assignments, prevents the convergence of the model results. This paper analyses the above uncertainty sources on the basis of multiple model runs conducted for this study. Three averaging procedures are investigated and compared. Practical considerations regarding setting up the averaging procedures required for obtaining stable model results are discussed.