The freight modal split model is designed to function with other models that perform the generation, distribution, and assignment tasks for freight flows and for passenger flows in the context of regional transportation planning. The variables that effect a firm's choice among available transport modes were identified and considered in the formulation of the model. It was assumed that information regarding the commodity type to be shipped, the average size of shipment, the transit time, etc., was known. The freight modal split model then determined the percent of the freight that would travel by each alternate form of transport. The quantity shipped by each mode can be determined by multiplying the percent obtained from the model by the total quantity to be shipped. Preliminary testing of the freight modal split model was limited to calibration using multiple regression techniques, and comparison of the available data with results calculated using the calibrated model. The results of the preliminary tests indicate that the proposed freight modal split model will be a valuable tool for regional transportation planning. (Author/publisher)
Abstract