Cumulative Interarrival Time Distributions of Freeway Entrance Ramp Traffic for Traffic Simulations

  • Erdinç Öner
Keywords: signalized, non-signalized, traffic modelling, headway, Kolmogorov-Smirnov test


Cumulative interarrival time (IAT) distributions for signalized and non-signalized freeway entrance ramps were developed to be used in digital computer traffic simulation models. The data from four different non-signalized entrance ramps (three ramps with a single lane, one ramp with two lanes) and two different signalized entrance ramps (both with a single lane) were used for developing the cumulative IAT distributions. The cumulative IAT distributions for the signalized and non-signalized entrance ramps were compared with each other and with the cumulative IAT distributions of the lanes for freeways. The comparative results showed that the cumulative IAT distributions for non-signalized entrance ramps are very close to the leftmost lane of a 3-lane freeway where the maximum absolute difference between the cumulative IAT distribution of the leftmost lane of a 3-lane freeway and the entrance ramps cumulative IAT distribution was 3%. The cumulative IAT distribution for the signalized entrance ramps was found to be different from the non-signalized entrance ramp cumulative IAT distribution. The approximated cumulative IAT distributions for signalized and non-signalized entrance ramp traffic for any hourly traffic volume from a few vehicles/hour up to 2,500 vehicles/hour can be obtained at


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How to Cite
Öner E. Cumulative Interarrival Time Distributions of Freeway Entrance Ramp Traffic for Traffic Simulations. Promet - Traffic&Transportation. 1;25(1):1-12. DOI: 10.7307/ptt.v25i1.1242