Measurement of spatial inequity in the accessibility to the public bus network: the case of Santa Fe de la Vera Cruz city, Argentina

Abstract

Transport facilities and mobility policies, largely dependent on the public sector, determine urban growth, living conditions of the population and performance of organizations, by facilitating (or hindering) mobility and access to opportunities in the city. This could cause social discrimination, which could be assessed from the perspective of the spatial justice, the avoidance or correction of which would imply public intervention.

In this paper, based on the spatial distribution of public bus stops in the city of Santa Fe (Argentina), and of the population (categorized into two levels of vulnerability - deprivation), it is intended to measure the magnitude and significance of social inequalities in spatial access to public transport within the city as a whole and disaggregated in its eight administrative districts.

To this end, 300 meters Euclidean distance was established as the optimal range of stops, in accordance with experts’ criteria, and considering walking as travel mode. The spatial coincidences / divergences between degree of proximity and the category of vulnerability - deprivation of the population were analysed using various statistical techniques (association coefficients such as Phi ɸ, Cramer's V, Pearson's contingency coefficient, and Gamma γ), and to establish the possible spatial injustice, the scale-diagram of spatial justice and an inferential test based on the χ² were applied.

The results evidenced the existence of vertical spatial inequity in access to the bus network in the city as a whole and that the Northern, coastal and part of the Western border area were the most disadvantaged zones, and at the same time, had a lower degree of accessibility to this service, mainly due to its remoteness to bus stops.