Retrospective test on the forecasting efficacy of PI models with different parameters for the Tohoku-Oki M_W9.0 earthquake

In this paper, the local area （32.0°N–46.0°N, 136.0°E–148.0°E） of Japan was chosen to be the studied region to verify the predictability of the pattern informatics （PI） method under different models with different parameters, using the receiver-operating characteristic （ROC） curve test andR score test. Pattern informatics （PI） method was applied to retrospec-tive study on the forecasting of large earthquakes in this region, especially the 2011 Tohoku-Oki M_W9.0 earthquake. Different forecasting hotspot maps with different parameters were obtained. The grid size were 0.5°×0.5° and 1.0°×1.0°, and forecasting window length was 5 to 10 years respectively. The results showed that, PI method could forecast the Tohoku-Oki M_W9.0 earthquake under most of the models, and the hotspots appeared in M_W9.0 earthquake’s epicentral grid or its Moore neighborhood grids. The ROC test andR score test analysis revealed that the forecasting effect was better for the models with larger grid size and longer window length compared to other models.