Transportation research project “Beyond Business as Usual: Ensuring the Network We Want is the Network We Get”.

Abstract This research assesses the implications of existing trends on fu-ture network investment, comparing alternative scenarios concerning budgets and investment rules. The main scenarios compare “stated decision rules”, processes encoded in flowcharts and weights developed from official doc-uments or by discussion with agency staff, with “revealed decision rules”, weights estimated statistically based on observed historical behavior. This research specifies the processes necessary to run the network forecasting models with various decision rules. We find that given the relatively small amount of funds available for network growth in a mature system, alternative decision rules make only small differences in overall system performance, though they direct investments to very different locations and affect the trip time and spatial accessibility in a significantly different way