MEASURING TRANSPORTATION: TRAFFIC, MOBILITY, AND ACCESSIBILITY

This article compares 3 approaches to measuring transportation system performance. Traffic-based measurements evaluate motor vehicle movement; mobility-based measurements evaluate person and freight movement; and accessibility-based measurements evaluate the ability of people and businesses to reach desired goods, services, and activities. The various perspectives represented by the approaches are discussed, and the decision process, involving how the selection of one method or another is made and can affect planning outcomes, is examined.