Modelling Distribution of External–Internal Trips and Its Intra-region and Inter-region Transferability

Estimating external–internal (EI) trips is an important component of travel demand modelling which is ignored in earlier studies. This study describes conventional and standardized regression models to analyse EI trips in Karachi metropolis, Pakistan, and in three cities in Belgium. Model development relies only on the travel survey data to obtain travel information of the residents of the study area and on open source platforms for land use and transport network information. Intra-region and inter-region transferability of the model is examined through four transfer methods: naïve, intercept update, coefficients update and standardized regression. Results revealed that the standardized regression model is most suitable for model transferability between two regions. Furthermore, land use profile and type of the study area are the two most significant factors that govern the transferability. The results will help estimate EI trips and incorporate them in the travel demand model estimation.