Feasibility study on potential accessibility indicators to schools (PT)

Use case adapted from the UN-GGIM Europe report on “Data Integration – Definition of priority user needs for combinations of data” published in October, 2015.


The motivation to develop accessibility indicators was raised in the context of the Statistical Council (and the creation of Working Group on Territorial Mobility). The idea was to produce a new type of indicators within the scope of the National Statistical System, taking advantage of the development of a Spatial Data Infrastructure and of spatial analysis techniques.

The feasibility study was based on a case-study approach. Four territorial units were selected based on principles such as urban vs. rural areas, population density and distribution (intense vs. scattered). Also schools from different levels of educations were selected.

Two types of potential time distance indicators were developed based on the minimum time distances between each geographical unit of input (census tracks, grid and buildings) and schools. These were calculated by different modes of transport (on foot and by car). The Information Reference Geographical Database (BGRI) and the Census Population Data were used, as well as a road network layer and a polygon geographical database on schools.

The sensibility analysis focused on the comparison of the potential time-distance indicators calculated for a specific output level based on different geographical units of input, as shown in the following two figures, the first one regarding population accessibility and the second one regarding territorial accessibility.

PT feasibility 1      

Time distance to the closest pre-primary school on foot by statistical subsection [Oeiras municipality]

PT feasibility 2

Time distance to the closest pre-primary school on foot by 1 km square grid [Oeiras municipality]