Speed Behavior Indicators Based on Floating Car Data: Results of a Pilot Study in Belgium

Abstract

This study investigates the use of floating car data (FCD) to monitor free flow speeds on the Belgian road network. Vehicle speeds were obtained from GPS signals emitted at 500 selected locations during the whole year 2013. Over 17 million individual vehicle speeds were analyzed. The results show that, although FCD are not specifically designed for this type of measurement, they allow obtaining free flow speed indicators with acceptable levels of precision. This is very encouraging because it provides a scope for monitoring free flow speed at a much higher temporal and spatial frequency than is currently possible with traditional road side measurements. The results also illustrate a number of methodological challenges, most notably, controlling for potential sources of bias in sampling the driver population. As subsequent work will enable to overcome these challenges, we conclude that FCD provide a feasible and attractive alternative for obtaining speed indicators.