Does modal choice between car and public transport really exist?


V Kaufmann

Document Type

Conference Paper

Publication Date


Subject Area

mode - car


Since Max Weber (1922), we have known that instrumentality is not the only logic underlying individual behaviour. As Boudon (1995) reminds us, the "rational choice" even becomes a special case when the alternative choices have an equivalent social value. However, the a priori of an instrumental rationality of the user, depending on the travel time, underlise the economy of transport, from the modelisation of practices (Henscher & Stopher, 1979), to the planning of large infrastructures (Merlin, 1985). It consists of assuming that the individual tries to minimise his travel times, and that is the factor at the origin of modal practices. This proposition even occasionally goes as far as being presented as a "law" of human behaviour which could only be countered by financial difficulties. Translated into everyday language, it leads to the equation" the shorter the better" For several decades now, many European municipalities have been embarking on policfes of "modal transfer'", or peIicies aimed at transferring the use of the car to other means of transport. To this effect, and in keeping with the theory of rationality in accordance with duration, public authorities plan to enhance the performance of public transport networks in order to bring them, up to standard" in comparison with what is offered by the car. In pursuit of this objective, they are committing themselves, to heavy investment in infrastructures, such as constmction, of a tram, or maderground network. However, experience shows that these development policies of alternatives prove disappointing in terms of impact on modal distribution : generally, an increase in the number of public transport users is recorded, but without a concomitant reduction in car traffic (Guidez, 1995). The modal transfer observed occurs to the detriment of walking and cycling (Salomon et al., 1993), which is of course not the aim of the exercise. Obviously, the massive improvement of public transport does not in itself allow the increase in use of the car to be stopped. A closer study of the rationalities underlying users' modal practices has been the purpose of a research project carried out at the IREC (Kaufmann & Guidez, 1996 ; Kaufmann & Stofer, 1995), some of the principle results of which are presented by this paper2.


Permission to publish abstract given by AET.