I have posted a number of analyses on this board showing that the statistics favor
a non-illusion explanation for this phenomena. The total area of the earth covered by
the rings is about 12-13 % of the total surface. The number of NEIS (M>=4) earthquakes
occurring within these rings after large earthquakes is consistently between 20 and 50%
of the total number of occurring earthquakes, well above what would be expected
randomly. However, it would be good to have the analysis automated somehow,
I cannot always find the time to do it and so sometimes it doesn't get done. I will try
to find references to those posts and post those references.