- A presentation of the model parameters and comparison of the median ground-motion values from the NGA-West2 GMPEs is presented for a suite of deterministic cases. In general, the median ground motions are similar, within a factor of about 1.5-2.0 for 5 < M < 7 and distances between 10-100 km Differences increase (on the order of 2-3) for large-magnitude (M > 8) earthquakes at large distances (R > 100-200 km) and for close distances (R < 10 km). A similar increase is observed for hanging-wall sites, and slightly larger differences are observed for soil sites as opposed to rock sites. Regionalization of four of the GMPEs yields similar attenuation rate adjustments based on the different regional data sets. All five GMPE aleatory variability models are a function of magnitude with higher overall standard deviations values for the smaller magnitudes when compared to the large-magnitude events.