A New Approach to Evaluate Long Term User Reactions to Changes in Transport Costs

Abstract

This paper presents a new application of the stated adaption survey method to analyze long term reactions to substantial changes in transport costs including different transport related energy-efficiency measures. Such long term reactions include: - choice of car type, motorization and usage, - choice of public transport season cards and usage (including substitution effects), - choice of residence, - while controlling for the influence of variables describing the residential environment and socio-demographics. The software-based survey includes two stated adaption experiments in which the respondents are requested to state their choice and usage of mobility tools given changes of transport costs and place of residence in the second experiment on a household level. In a third experiment, the respondents had to choose between two of self-defined earlier situations. In multi-persons households cars tend to be jointly used and also the place of residence is expected to be the result of collective decision process. Therefore, the survey considers the mobility tool ownership and its usage on a household level. The inclusion of car and public transport season card ownership is motivated by the finding of substitution between those two types of mobility tools in earlier studies. The extensive descriptive analysis of the data shows the applicability of the approach. Not only are findings from earlier studies on the topic confirmed, but also - due to the consideration of a broader range of factors and possible reactions considered- new insights about mobility tool ownership and residence location choice are provided: people react not only by adjusting mileage but also by changing car types and choosing smaller engines or more fuel efficient engine concepts such as Hybrids or Diesel. In addition, it is shown that also substitution effects between car and season card ownership within households play are important.