Estimation of marginal transport costs: the flow aggregation function approach

The zonal origin-destination (OD) marginal costs incurred by a national trucking system in Chile network are analyzed using a flow aggregation function approach. A Generalised Disjoint Aggregation Matrix was derived to estimate the costs which occur in moving an extra unit, with distance, topography, destination, volume level and system congestion as the relevant factors. The study generated zonal marginal costs with no linear relation to distance, and which were estimated at 14 US cents to 50 US cents per ton-kilometer. Volume became a significant factor to costs incurred within short hauls.