Evaluation of ETAS and STEP forecasting models for California seismicity using point process residuals

Joshua Ward, & Frederic P. Schoenberg

Submitted March 15, 2022, SCEC Contribution #11809

Variants of the Epidemic-Type Aftershock Sequence (ETAS) and Short-Term Earthquake Probabilities (STEP) models have been used for earthquake forecasting and are entered as forecast models in the purely prospective Collaboratory Study for Earthquake Predictability (CSEP) experiment. According to analyses by Schorlemmer et al. (2010) and Zechar (2013) the ETAS model appeared to offer the best fit for the first several years of CSEP. Here, we evaluate the prospective fit of the ETAS and STEP one-day forecast models for California from 2013-2017, using super-thinned residuals and Voronoi residuals. We find very comparable performance of the two models, with slightly superior performance of the STEP model compared to ETAS according to most metrics.

Key Words
CSEP, earthquakes, super-thinning, seismology, self-exciting point process, Voronoi deviance residuals.

Citation
Ward, J., & Schoenberg, F. P. (2022). Evaluation of ETAS and STEP forecasting models for California seismicity using point process residuals. Environmetrics, (submitted).