Method Comparison

Since each method has a different data requirement it is improper to compare the methods with the full dataset. For example, the CN method will sample geology at all back-azimuths relative to a station, whereas the RTS method is restricted to a narrow azimuthal window aligned roughly along a pair of stations and events. In an attempt to normalize the dataset used for each method, we restrict the data to lie in a small region along the Franciscan block (Figure 2.15a). We implement all five methods to calculate $Q_0f^\eta$ in the region (Figure 2.15b). The populations are then smoothed with a two-dimensional gaussian kernel ( Venables and Ripley, 2002) to produce an empirical distribution so that the 95% confidence region can be estimated. The grey region in Figure 2.15 represents a parameter space that fits all studies.

Figure 2.15: Method comparison. a) Map of the subset used in the comparison analysis. Data are in a small region near the San Francisco Bay Area, primarily along the Franciscan block. b) Power-law parameters and their empirical 95% confidence regions are given. The intersecting region is shaded grey.
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