Impact of speed limit changes on urban streets

Project summary:

This project is using the change in speed-limit law as an opportunity to study the effect of speed-limit changes on vehicle speeds. After identifying Minnesota cities planning to change speed limits and willing to serve as research partners, a sample of roads was selected for a before-and-after study of how changes in speed limits affect vehicle speeds.

By estimating changes in speed distributions that follow speed-limit changes, while controlling for trends and possible location-based confounding effects, researchers expect new information to be produced on where and to what degree speed-limit changes are effective. This information is being used to develop guidance on when speed-limit changes are likely to achieve the desired effect.