Figure 1

Cross-evaluation of the EEPAS and EAST _R models in California for M ≥ 4.95 target earthquakes. (a) Retrospective period from January 1984 to June 2009. (b and c) Quasi-prospective period from July 2009 to December 2011. We consider the entire CSEP testing region in (b) and a reduced region in (a) and (c) to exclude off-coast and outside USA areas (Shebalin et al. 2011). Using Molchan diagrams, we compare the forecasts of the EAST _R model with respect to the EEPAS model (red lines) and vice versa (blue lines). The dashed diagonal line corresponds to an unskilled forecast. The shaded area indicates the zone in which the prediction of the tested model outperforms the prediction of the reference model at a level of significance α=1%. For both the EEPAS and the EAST _R models, we consider single rate values obtained by summing the expected rates of M≥4.95 target earthquakes.