Other statistics derived from the meta-analysis.
a. Differences in methods employed to argue in favour of loading by aseismic slip or in favour of earthquake triggering. Statistical approaches with use of stacking methods (large data set analysis) tend preferentially towards an earthquake triggering origin of foreshocks. Arguments for loading are mostly based on the study of individual foreshock sequences. b. Evolution of thoughts and methods through time. Popularity of the triggering view has increased over time with the development of statistical studies based on stacking methods. Since the 2000's, there is no clear preference for any given theory of foreshock origin, showing that the debate continues.