Analysis of Urban Traffic for Various Sets of Vehicles

Abstract

The paper analyses the results of traffic flow measurements recorded by road traffic and noise monitoring station. The station is located in a medium size city in Poland (Kielce) situated at the national road to Cracow. The traffic flow was measured over the period between January and December 2013 for twenty-four hours a day. The measurements were documented at one hour intervals throughout the 24-hour period (0:00-23:00). Statistical analysis methods were used to determine the variability and uncertainty of the results. The measurements from two vehicular lanes running towards the town (L12) and two lanes running towards Cracow (L34) were analysed. Different vehicle sets (G(i)) were taken into account: i = cars, trucks, delivery vans and motorcycles. The coefficients of variation and positional variation were proposed for the analysis of traffic data scattering. It was found that in some cases the distribution of the tested variable was not normal. Differences in traffic intensity on opposite road lanes for particular sets of vehicles were demonstrated. Box plots were used to assess whether outliers occurred in the recorded data. The times of the day at which the parameters describing the variability of the recorded traffic stabilized were identified. The results obtained for the data recorded on working and non-working days were compared. Type A uncertainty was evaluated.