1. Potential Accessibility Indicators to Schools
Potential Accessibility Indicators to Schools
A Preliminary Study
EUROSTAT Working Party Meeting
30 September – 1 October 2013

2. Potential Accessibility Indicators to Schools
A Preliminary Study
1. Context
To develop Accessibility Indicators to different types of facilities and to assess their possibility of regular production within the national statistical system – National Statistical Council
Make use of the Spatial Data Infrastructure to support statistical production and dissemination and to take advantage of spatial analysis techniques to produce new statistical information – National Statistical System programme
2. Potential Time-Distance Accessibility Indicators
Two types of potential accessibility indicators based on the weighted average of the minimum distances between each Census tracks and schools:
Territory – weighted by the area (m2)
Population – weighted by the population from the specific age group
Territorial Statistics Unit and Geo Information Unit
EUROSTAT Working Party, 30 Sept.-1 Oct. 2013

3. Urban and densely populated Rural and intense/ structured
Potential Accessibility Indicators to Schools
A Preliminary Study
3. Methodology
Experimental study based on a case-study approach
Four territorial units were selected based on the following principles: urban vs. rural areas, population density and distribution (intense vs. scattered)
Urban and scattered
Urban and densely populated
Rural and intense/ structured
Rural and scattered
Basic – 1st cycle
Pre-primary
Secondary
Territorial Statistics Unit and Geo Information Unit
EUROSTAT Working Party, 30 Sept.-1 Oct. 2013

4. Potential Accessibility Indicators to Schools
A Preliminary Study
3. Methodology
Databases
Census tracks BGRI: geographical database of PT territory
Census population data
Road network layer
Point geographical database on schools
Potential territorial accessibility
Potential population accessibility
Modes of transport
Type
Speed
On foot
4,3 km/h
By car
Highway
120 km/h
Outside localities
90 km/h
Inside localities
50 km/h
Where:
LAU 2
statistical subsection
level of education
school of level of education
Territorial Statistics Unit and Geo Information Unit
OECD – WTPI, 17-18th June 2013

5. Potential Accessibility Indicators to Schools
A Preliminary Study
4. Data Model
Road network model limitations: i) all two-way roads; ii) one speed limit by type of road; iii) no vertical or horizontal road signs
ArcGIS Network Analyst – Dijkstra’s algorithm (1959) to compute the shortest path
Statistical section
X and Y
geometric centroid
Statistical subsection
contiguous territory belonging to a unique civil parish (LAU 2) and containing about 300 housing units
the lowest delimited area within a statistical section - quarter
Territorial Statistics Unit and Geo Information Unit
EUROSTAT Working Party, 30 Sept.-1 Oct. 2013

6. Urban and densely populated
Potential Accessibility Indicators to Schools
A Preliminary Study
Census statistical subsection  LAU 2
5. Results
Potential TERRITORIAL accessibility to basic education/1st cycle – on foot (LAU2)
Urban and densely populated
Potential POPULATION accessibility to basic education/1st cycle – on foot (LAU2)
Territorial Statistics Unit and Geo Information Unit
OECD – WTPI, 17-18th June 2013

7. Potential Accessibility Indicators
Potential Accessibility Indicators to Schools
A Preliminary Study
6. Limitations and work in progress
To increase the robustness of the network and keeping it updated – commercial vs. official
Population accessibility indicators depending on Census data (every ten years) vs. Territorial potential accessibility indicators can be updated within this period
To extend the study to other type of facilities: e.g Health (hospitals and official clinics), Culture (museums, cinemas) and Justice (courts) – Spatial Data Infrastructure for statistical production
INPUT
OUTPUT
Time-Distance
Potential Accessibility Indicators
Buildings
Grids
LAU 2
LAU 1
NUTS 3
Census
Tracks
To distinguish between characteristics of schools – public vs. private
To extend calculations to more geographical levels – accuracy vs. data processing
Territorial Statistics Unit and Geo Information Unit
EUROSTAT Working Party, 30 Sept.-1 Oct. 2013

8. THANK YOU! Potential Accessibility Indicators to Schools
A Preliminary Study
THANK YOU!
Territorial Statistics Unit and Geo Information Unit
EUROSTAT Working Party, 30 Sept.-1 Oct. 2013