The demand for urban transport: An application of discrete choice model for Cadiz.
1.- Introduction
Although Cadiz is a city of reduced extension, it has important traffic jam problems due to
its geographic configuration, to the high density of inhabitants near 16.000 inhabitants per
square kilometers and to be the administrative centre of the province, these facts take away
life quality to its inhabitants. In this way the public iniciatives are centred in political
movements that promote the use of colective transport to get a model and more equilibrated
distribution, between urban and private transport.
In this context, with this essay, we have tried to make an estimation of demand of transport
when the individuals must make a choice between two alternatives, urban and private
transport, according to a discrete choice model like the probit model. This model is based
on the theory of aleatory utility that means the existence of rational customers who take
their consume decisions maximizing its utility, including like explicative variables the
urban transport attributes and the individual socioeconomic caracteristics. This allows to
calculate the elasticities of demand according to the price and the time of the travel that can
help to the design of urban transport politics that decreases traffic jams improving social
comfortable living.
This essay is centred in the estimation of the demand for private transport in Cadiz city for
the displacements due to work where the individuals decide what kind of transport
maximizes their utility, planning a binomial choice model between car and bus. For this
reason in the second section we expose the methodology used for the estimation of the
function of the demand for transport, in the third section it is made the treatment and the
analysis of the sample esteeming the model in the fourth section; the exploitation of the
results is made in the fifth section with the computation of direct and crossed elasticities,
the essay is finished with the attainment of the main conclussions.