A sampling design for the evaluation of earthquakes vulnerability of the residential buildings in Florence

The assessment of earthquakes vulnerability of buildings is a key step in the analysis of seismic risk of a territory. The aim of this study is the identification of an appropriate sampling design for the analysis of the earthquake vulnerability of the residential buildings in the city of Florence. In order to identify such a design we have considered that the buildings are statistical units selected from a territory and therefore could be spatially correlated. Since in these cases it is advantageous to select units well spread over the territory, we propose a spatial balanced sampling design. In addition to the information on the geographical location of each building, the suggested sampling design takes into account other auxiliary information on characteristics of the buildings that may affect their vulnerability.