How Spatial and Transport Planning Affects Car and Public Transport Ownership. A Panel Data Simulation

This paper describes how individual travel behavior is influenced by long term commitments due to the ownership of cars and public transport passes. The paper shows how a sound forecast of car ownership is crucial for accurate estimates of future mobility trends and planning strategies’ impact on travel demand. These forecasts are traditionally based upon models that take into account demographic and economic trends. However, most car ownership models ignore that planning strategies could influence car ownership decisions by reducing (or increasing) the need for (multiple) car ownership. In urban areas with good accessibility by alternative modes, many households live with no or only one car even if they could afford a second vehicle. This paper analyzes the residential location choice and life course event and the availability of cars, public transport passes and driving licenses using discrete choice models. First, the paper investigates, how accessibility to shops and services are linked to car and public transport pass ownership using a survey of 4,500 households in the Hanover region. It shows, that motorization levels more than double from the most to the least accessible areas within the region, when controlling for socio-economic variables. Second, it uses data from the German Socio-Economic Panel (GSOEP) and the Mobility-Panel (MOP) to estimate a dynamic model of household acquisition and the disposal of cars and public transport passes. The paper analyzes the impact of life course events, residential location choice and accessibility on these decisions. The model will be applied as part of a micro-simulation of mobility tool ownership for a synthetic population in order to estimate the effects of planning strategies and transport investments on car and public transport pass ownership.