Carpooling and the reduction of urban traffic

The article presents the results of research that quantitatively confirm the well-known thesis on the impact of carpooling (measured by the declared carpooling indicator, DCI) on a significant reduction in the intensity of urban traffic flows. Of course, it is about joint journeys by passenger cars, which (especially in medium-sized and large cities) are an important source of transport congestion, and the connection with the intensity of traffic is obvious. The working hypothesis was verified by conducting observations and measurements in the central area of a medium-sized city in Poland. It is the city of Radom, 100 km south of Warsaw, with a population of 215,000. residents. To verify the hypothesis, the average daily traffic volume, ADTV were compared with the average reduced average daily traffic volume, RADTV. These were determined - by simulating carpooling, in which the main control variable (although not the only one) was the indicator, DCI, i.e. the number of additional passengers in a passenger car. It turned out that RADTV values decreased significantly (therefore congestion decreased) when DCI values increased. This is illustrated by the DCI - RADTV dependence graphs for different days of the week and different measurement locations. This relationship was confirmed by calculating the Spearman's rank correlation index between the DCI and RADTV variables.