Open Data: una sperimentazione di dati spaziali ad accesso libero

Many GIS-based projects are often hindered by the lack of cartographic data, mainly in case of high-detailed analysis of spatial phenomena. A very sore point of Italian scenario is address georeferencing; in fact, apart from a few number of local cases, Italian public administrations do not have yet produced complete and affordable numerical cartographic data. On the contrary some commercial companies, which operate in the field of the Geographic Information, own such data and they allow free download of geographic coordinates of civic addresses, with the possibility of importing them in a user application. This study aims to test the use of data free downloaded from the Internet; the case study is a project on the effects of traffic-related air pollution on respiratory health of a schoolchildren sample living in Palermo (Sicily). The students participating in the survey provided their residence addresses. Addresses geocoding was made gaining access via web to a commercial service (Google Maps), by means of an API (Application Programming Interface), provided by the service itself. For the access a Javascript code was implemented. The service provided the coordinates for 700 addresses out of the 715 requested; we accepted 673 adresses (94% of the request).