Classification of composite seismogenic sources through probabilistic score indices

Six out of the ten natural disasters that caused the largest financial losses are earthquakes. If their forecasting is still, and will probably remain for a long time, an unsolved problem, however, it is time to start to draw up medium- and long-term protocols to be followed for the reduction of seismic risk. To do that we have to speak of prevention and of priorities of intervention, which imply the classification of the zones on the basis of their proneness to the seismic risk. In one of the possible probabilistic and geophysical frameworks supported by the present knowledge, some scoring procedures are presented which aim at different goals: comparing models, measuring their performance, identifying their limits, providing tools to the decision makers.