Editing Earthquake prediction (section)

==== Seismicity patterns ====
{{anchor|M8}} {{anchor|PI}}

Various heuristically derived algorithms have been developed for predicting earthquakes. Probably the most widely known is the M8 family of algorithms (including the RTP method) developed under the leadership of [[Vladimir Keilis-Borok]]. M8 issues a "Time of Increased Probability" (TIP) alarm for a large earthquake of a specified magnitude upon observing certain patterns of smaller earthquakes. TIPs generally cover large areas (up to a thousand kilometers across) for up to five years.<ref>See details in {{Harvnb|Tiampo|Shcherbakov|2012|loc=§2.4}}.</ref> Such large parameters have made M8 controversial, as it is hard to determine whether any hits that happened were skillfully predicted, or only the result of chance.

M8 gained considerable attention when the 2003 San Simeon and Hokkaido earthquakes occurred within a TIP.<ref name=":11">{{Harvnb|CEPEC|2004a}}.</ref> In 1999, Keilis-Borok's group published a claim to have achieved statistically significant intermediate-term results using their M8 and MSc models, as far as world-wide large earthquakes are regarded.<ref>{{Harvnb|Kossobokov|Romashkova|Keilis-Borok|Healy|1999}}.</ref> However, Geller et al.<ref name=":12">{{Harvnb|Geller|Jackson|Kagan|Mulargia|1997}}.</ref> are skeptical of prediction claims over any period shorter than 30 years. A widely publicized TIP for an M 6.4 quake in Southern California in 2004 was not fulfilled, nor two other lesser known TIPs.<ref>{{Harvnb|Hough|2010b|pp=142–149}}.</ref> A deep study of the RTP method in 2008 found that out of some twenty alarms only two could be considered hits (and one of those had a 60% chance of happening anyway).<ref>{{Harvnb|Zechar|2008}}; {{Harvnb|Hough|2010b|p=145}}.</ref> It concluded that "RTP is not significantly different from a naïve method of guessing based on the historical rates [of] seismicity."<ref>{{Harvnb|Zechar|2008|p=7}}. See also p. 26.</ref>

{{anchor|AMR}}''Accelerating moment release'' (AMR, "moment" being a measurement of seismic energy), also known as time-to-failure analysis, or accelerating seismic moment release (ASMR), is based on observations that foreshock activity prior to a major earthquake not only increased, but increased at an exponential rate.<ref>{{Harvnb|Tiampo|Shcherbakov|2012|loc=§2.1}}. {{Harvnb|Hough|2010b|loc=chapter 12}}, provides a good description.</ref> In other words, a plot of the cumulative number of foreshocks gets steeper just before the main shock.

Following formulation by {{Harvtxt|Bowman|Quillon|Sammis|Sornette|1998}} into a testable hypothesis,<ref>{{Harvnb|Hardebeck|Felzer|Michael|2008|loc=par. 6}}.</ref> and a number of positive reports, AMR seemed promising<ref>{{Harvnb|Hough|2010b|pp=154–155}}.</ref> despite several problems. Known issues included not being detected for all locations and events, and the difficulty of projecting an accurate occurrence time when the tail end of the curve gets steep.<ref>{{Harvnb|Tiampo|Shcherbakov|2012|loc=§2.1|p=93}}.</ref> But rigorous testing has shown that apparent AMR trends likely result from how data fitting is done,<ref>{{Harvnb|Hardebeck|Felzer|Michael|2008|loc=§4}} show how suitable selection of parameters shows "DMR": ''Decelerating'' Moment Release.</ref> and failing to account for spatiotemporal clustering of earthquakes.<ref>{{Harvnb|Hardebeck|Felzer|Michael|2008|loc=par. 1, 73}}.</ref> The AMR trends are therefore statistically insignificant. Interest in AMR (as judged by the number of peer-reviewed papers) has fallen off since 2004.<ref>{{Harvnb|Mignan|2011|loc=Abstract}}.</ref>