Proposing an integrated accessibility-based measure to evaluate spatial equity among different social classes

Fair spatial distribution of services has always been a challenge for urban planners to supply sufficient accessibility for individuals and to consider the needs of vulnerable social groups. Nevertheless, equity assessment literature has mostly focused on measuring the accessibility through distance-based variables, and social stratification based on just income, as well. Accordingly, this study intends to employ an accessibility measure that considers non-distance-based variables along with distance-based ones. It uses multi-criteria decision-making to propose an accessibility index to assess vertical and horizontal equity of residents’ accessibility to a range of public facilities, in the district 6 of Tehran, Iran. Therefore, using the integration of geographical information system-based spatial analysis, wider people specification, and the Gini coefficient, this measure proposes a novel framework to examine the equity level of individuals belonging to the lower, middle, and upper social classes. Results imply a 0.228 Gini index for horizontal equity, which indicates a low level of inequity among residents. Besides, for vertical equity evaluation, Gini index of 0.097, 0.249, and 0.167, respectively, for lower, middle, and upper groups show people in the lower class experience very low levels of inequity, therefore higher accessibility is well distributed among groups with higher social needs. This approach can help planners to choose the right analysis method and prioritize urban decisions toward the equitable distribution of facilities.