Epistemic uncertainty in on-site earthquake early warning on the use of PGV–PD3 empirical models.

From the literature, we found that PGV–PD3 regressions for on-site earthquake early warning (EEW) can be quite different depending on the presumption whether or not PGV–PD3 data from different regions should be “mixable” in regression analyses. As a result, this becomes a source of epistemic uncertainty in the selection of a PGV–PD3 empirical relationship for on-site EEW. This study is aimed at examining the influence of this epistemic uncertainty on EEW decision-making, and demonstrating it with an example on the use of PGV–PD3 models developed with data from Taiwan, Japan, and Southern California. The analysis shows that using the “global” PGV–PD3 relationship for Southern California would accompany a more conservative EEW decision-making (i.e., early warning is activated more frequently) than using the local empirical model developed with the PGV–PD3 data from Southern California only. However, the influence of this epistemic uncertainty on EEW is not that obvious for the cases of Taiwan and Japan. [ABSTRACT FROM AUTHOR]