Improved accessibility modeling and its relation to poverty - A case study in Southern Sri Lanka

Many studies have found close relationships between accessibility and various socio-economic indicators. Yet, since accessibility tends to have differentiated effects, both socially and spatially, there is a need for a model which allows for a disaggregated analysis of accessibility. The model should be possible to use in areas where road network data is incomplete. In this paper such an accessibility model is developed, using a raster-based approach in a Geographical Information System (GIS). One important factor in accessibility modeling is to estimate the traveling speed on different landscape entities. This paper develops a method where local knowledge and physical geographical data are integrated in the GIS model. From the interview data the best door-to-door traveling speeds of three road classes were estimated. The results from these calculations have been used as frictions for a cost surface. The analysis shows strong relationships between poverty indicators and estimated spatial accessibility, stronger than the commonly used accessibility measure of Euclidian distance. (C) 2010 Elsevier Ltd. All rights reserved.