Spatial Econometric Analysis of Automobile and Motorcycle Traffic on Indonesian National Roads : Is It Local or Beyond City Boundaries?

This paper investigates the spatial dimensions of automobile and motorcycle trips on national roads between neighboring cities in Indonesia, using spatial econometric models. Vehicle trips are measured in terms of vehicle kilo- meters traveled (VKT) for both types of vehicles. The study finds that motorcycle trips are characteristically local because there is no sign of a spatial correlation with neighboring cities for such trips; by contrast, automobile trips are often made across city boundaries, although the models demonstrate only small spatial correlations among neighboring cities for automobile trips. The models also indicate that road capacity, gasoline prices, income in the region, population and worker density, city size, and number of public buses, have significant effects on VKT. The results suggest that in general, urban transportation policies for national roads could be less complex because local solutions may be more effective in solving the traffic problems of individual Indonesian cities.