- See Section 2.247.
- Response parameter is pseudo-acceleration for 5% damping.
- Compares predictions to observations grouped into 1-unit magnitude bins at 0.3 and 1.0s and finds equations are reasonable description of data. Also compares predictions to observations from large magnitudes events and from close distances and finds that equations would overestimate short-period motions from large events at close distances.
- Compares overall distribution of residuals for 0.3s with normal distribution. Finds that residuals generally follow normal distribution but data shows greater number of large-residual observations that predicted by normal distribution, most of which come from a single event (22/02/2000 M3.24) recorded at > 100km. Finds no evidence for truncation of residuals up to three standard deviations.
- For analysis of Landers events, regresses 0.3s data for 10 stations with more than 50 records using same functional form without distance terms (since distances are almost constant) to get site-specific equations. Find on average σ = 0.19±0.04. Therefore concludes single station-single source standard deviations much lower (60%) than standard σs.
- Notes that decreasing σ with increasing period could be due to dominance of small events for which long-period motions are at the moment end of the spectrum, which should be correlated with M and independent of stress drop.