Methods for analysing observed compliance rates to mandatory speed limits.

This paper describes new results obtained within an interdisciplinary study of the effectiveness of current and proposed preventive control strategies on German motorways. Currently no definite guidelines exist in Germany with respect to methods for presenting information through Variable Message Signs (VMS) and to the suitable spacing between consecutive VMS. The present paper focuses on empirical measurements of traffic flow characterising response to VMS. Two statistical methodologies (linear regression and transfer function model) were applied to investigate compliance with VMS. The results of this analysis are intended to provide recommendations to the German Federal Highway authorities for improving the effectiveness of VMS in traffic management.