- Ground-motion model is:
where y is in cm∕s2, b1 = 1.04159, b2 = 0.91333, b3 = -0.08140, b4 = -2.92728, b5 = 0.28120, b6 = 7.86638,
b7 = 0.08753, b8 = 0.01527, b9 = -0.04189, b10 = 0.08015, σ1 = 0.2610 (intra-event) and σ2 = 0.0994
- Use three site categories:
- SS = 1, SA = 0.
- SA = 1, SS = 0.
- SS = 0, SA = 0.
- Use three faulting mechanism categories:
- FN = 1, FR = 0.
- FN = 0, FR = 0.
- FR = 1, FN = 0.
- Use same data as Akkar and Bommer (2007b) (see Section 2.267) but repeat regression analysis for
pseudo-spectral acceleration (rather than for spectral displacement), assuming homoscedastic variability,
reporting the coefficients to five decimal places and not applying any smoothing. These changes made due
to shortcomings revealed in GMPEs of Akkar and Bommer (2007b) after their use in various projects that
required, for example, extrapolation outside their magnitude range of applicability and work reported in
Bommer et al. (2007) (see Section 2.271) and other studies.
- Examine total, inter- and intra-event residuals w.r.t. Mw and rjb and found no apparent trends (shown
for a selection of periods). Note that some plots suggest magnitude-dependent variability but insufficient
data to constrain it.