  [Tormann et al., 2014] propose a distance exponential weighted (DEW) b-value
mapping approach as an improvement to previous methods of constant radius and
nearest neighborhood. To test the performance of their proposed method the
authors introduce a score function. This score function is applied on a
semi-synthetic earthquake catalog to make inference on the parameters of the
method. In this comment we argue that the proposed methodology cannot be
applied to seismic analysis since it requires a priori knowledge of the spatial
b-value distribution, which it aims to reveal.
