What if autonomous vehicles had been introduced into cities? A counterfactual analysis

The impact of autonomous vehicles on the spatial size of cities remains ambiguous, as the future is highly uncertain. This paper uses counterfactual analysis techniques to examine the effects of autonomous vehicles on urban expansion for metropolitan areas in the United States if autonomous vehicles had been introduced before. We argue that distance cost and congestion cost, which are the two components of transportation cost with different effects on urban expansion, should be addressed in autonomous vehicle research. By coupling historical data with hypothetical scenarios of introducing autonomous vehicles to cities, we find that urban expansion, rather than urban densification, would have been the dominant effect if autonomous vehicles had been introduced into cities. The finding indicates that if autonomous vehicles are widely adopted in the future, they are likely to have similar, or even larger, effects on future urban expansion than in the counterfactual past.