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Decreasing Highway Speed Using a Salient Variable Message Sign

General Information

Project description

To reduce the speed of motor vehicles on the Yarze highway, Nudge Lebanon, in collaboration with the Traffic Management Centre (TMC), placed a salient image of overlooking eyes, coupled with a message informing drivers that their speed was being monitored on a Variable Message Sign (VMS). Vehicles in treatment time slots, with speeds above 100km/h reduced their speed by around 11.5% compared to similar vehicles in the control group. Moreover, compared to the control group, the treatment was more effective for drivers with speeds in the 95th percentile compared to those in the 5th percentile, reducing their speed by about 5.6% in comparison. Disaggregating the data into speed brackets above the statutory limit indicates that noncompliant drivers in higher brackets exhibited greater reductions in speed (treatment compared to control) than drivers in lower brackets.

Detailed information

Final report: Is there a final report presenting the results and conclusions of this project?


Final report

Who is behind the project?

Institution: Nudge Lebanon
Team: Nudge Lebanon

Project status:



Methodology: Experiment, Field Experiment
Could you self-grade the strength of the evidence generated by this study?: 1

What is the project about?

Policy area(s): Road Safety
Topic(s): Compliance, Decision-making
Behavioural tool(s): Messenger effect, Prompts, Salience

Date published:

17 December 2021

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