Mohring effect

The Mohring effect is the observation that, if the frequency of a transit service (e.g., buses per hour) increases with demand, then a rise in demand shortens the waiting times of passengers at stops and stations. Because waiting time forms part of the costs of transportation, the Mohring effect implies increasing returns to scale for scheduled urban transport services.

The effect was named for the University of Minnesota economist Herbert Mohring, who identified this property in a 1972 paper.