Fig. 2From: Characteristics of foreshock activity inferred from the JMA earthquake catalogDistance measure using the nearest-neighbor distance analysis. a, b Schematic view, c, d the short-term data, and e, f the long-term data. a, c, e \(\log \eta\) histogram. The gray area shows the frequency of \(\log \eta\), the blue dotted line shows the optimal solution when assuming two Weibull distributions, and the red line shows the sum (theoretical value) of the mixed Weibull distribution. b, d, f Joint distribution with rescaled time T and rescaled distance R. The dashed line shows \(\eta_{0}\)Back to article page