A drop in the ocean? : behavioral spillover effects and travel mode choice

Abstract: This study aims to identify behavioral spillover effects related to travel mode decisions. In particular the effect of a shift towards environmentally friendly day-to-day commuting on occasional longer distance travel modes is explored. Therefore a natural experiment caused by the implementation of congestion charging in Stockholm and Gothenburg is exploited. In a fixed effects model with a control group, the average treatment effect on the treated is estimated by regressing the number of short-haul flight trips on a policy treatment dummy and the amount of the charge, respectively. The findings reveal predominantly positive estimates, confirmed and strengthened by various extensions, and thus point towards negative spillover effects.