Comment on pierce and shoup: Evaluating the impacts of performance-based parking

Adam Millard-Ball, Rachel Weinberger, and Robert Hampshire critically comment on Pierce and Shoup's article 'Evaluating the Impacts of Performance-Based Parking'. In principle, a performance-based parking system such as SFpark, which adjusts prices in a bid to achieve target occupancy for curb parking, is an excellent way to reduce congestion and to improve the driver experience. Pierce and Shoup's findings suggest that the SFpark program has had a remarkable impact in an extremely short time, an impact that is substantially faster and greater than that shown in other analyses. Their empirical analysis ignores the endogeneity of prices specifically the possibility that fluctuations in demand trigger price changes under SFparks rate adjustment rules. The authors feel that it is too soon to draw firm conclusions about the impact of performance-based parking pricing programs such as SFpark.