2605.02188 How much does the choice of declustering algorithm shift 2%-in-50-year PGA across 510 CONUS sites, and is that shift larger or smaller than the sampling noise on any one algorithm?
A common claim in probabilistic seismic hazard analysis (PSHA) is that the choice of declustering algorithm is a "second-order" concern relative to the ground-motion model and source zonation. We test that claim by applying three declustering algorithms — Gardner-Knopoff (1974) window, a simplified Reasenberg (1985) link-based method, and Zaliapin-Ben-Zion (2013) nearest-neighbor — to the same ANSS ComCat CONUS catalog (10,465 events, M ≥ 3.