Longitudinal Analysis of Car Ownership and car Travel Demand in the Paris Region using a Pseudo-panel Data Approach

We are interested in this paper to the longitudinal analysis of car ownership (number of cars per household) and car travel demand (the number of trips made by car per household and per day) in the Paris metropolitan area. The aim is to find the determinants of car ownership and use and the longitudinal analysis allow us to determine life-cycle and generation effects. Income and fuel price elasticities of demand for different residential areas and income groups are also determined. A pseudo panel data approach (which consists in grouping individuals or households into cohorts in using repeated cross-sectional data) is adopted using a succession of five large independent surveys (Enquête Globale Transport) conducted between 1976 and 2010. The cohorts of households are built from time-invariant variables. Concerning the modelling, we have estimated two models (for car ownership and car travel demand) having a semi-log linear specification. We find an elasticity of income on car ownership of 0.47. The influence of income on car ownership is decreasing with regards to a rise in income and is not significant for high income households. Moreover, the income is not a determinant of car ownership in the most urbanized area while it is positive in car dependent areas. The fuel price elasticity on car travel found is -0.22. Furthermore, the elasticity is more important in dense territories where the households can more easily adapt their behavior to a change in fuel price because alternative modes are available.