Fig. 4
From: CSEP Testing Center and the first results of the earthquake forecast testing experiment in Japan
Observed number of earthquakes in non-overlapping 3-month intervals since 1990. (a) “All Japan”, (b) “Mainland”, and (c) “Kanto”. The solid line shows the mean number along with two-sided bounds estimated from the standard deviation (dashed line) and two-standard deviations (dotted line). A filled square and a gray square in each figure show the number of earthquakes in the forecast period we study here and in the next 3-month period, respectively.