Comparison of INTEGRATION, TSIS/CORSIM and WATSim in Replicating Volumes and Speeds on Three Small Networks

INTRODUCTION TSIS/CORSIM and WATSim are microscopic, integrated, simulation models. INTEGRATION, on the other hand, models only the aggregate speed-volume interactions of traffic and not the details of a vehicle's lane-changing and car-following behavior; thus, it is commonly classified as a mesoscopic integrated simulation model. INTEGRATION is a routing-oriented model for mixed networks (1,2); vehicles' trip origins, destinations and departure times are specified external to the model. INTEGRATION has been applied to several projects (e.g., 3,4,5), and the model itself is under continuous improvement. Version 2.0 (6) was used in our tests. TSIS/CORSIM (7) is a combination of two microscopic models, NETSIM and FRESIM. Within the earlier integrated traffic simulation system (TRAF), the freeway/urban street system, ABSTRACT INTEGRATION, TSIS/CORSIM, and WATSim can simulate traffic operations on arterials and freeways in an integrated fashion. This paper presents comparisons using three small networks in Honolulu for which detailed and simultaneous flow conditions are known from surveillance tapes. The models produced reasonable and comparable results on most of the tested network links. Of the three software, only INTEGRATION can simulate U-turns, but it also is least able to model complex signal operations. TSIS/CORSIM is best at replicating lane-changing behavior, but its percentile input for off-ramps is both inconvenient and inaccurate. WATSim needed the least calibration for producing good results, but its animation is inferior and its universal car-following parameters are undesirable. The experiments also revealed that in no case did the default parameters offer satisfactory results. 3 simulated with the combination of NETSIM and FRESIM, were composite rather than integrated networks. A Windows version of TSIS (Traffic Software Integrated System) was developed to provide an integrated, user-friendly, graphical user interface and environment for executing CORSIM. The authors participated in the TSIS/CORSIM beta-testing and this paper includes parts of the tests undertaken (the results are with the version released to the public in June 1997). NETSIM's applicability to freeway and ramp operations. Features include those in TRAF-NETSIM plus HOV configurations, light rail vehicles, toll plazas, path tracing, ramp metering, and real time simulation and animation (8). This paper presents comparisons of these models based on results from three small networks. Simulated throughputs were compared with actual volumes and speeds. Selected specifications for the data are given below. (1) Freeway volumes were counted from videotapes by using AUTOSCOPE and by manually checking selected ramps and mainline segments. All freeway data used in the analyses are from …