- Ground-motion model is: where A is in m∕s2, c1 = -1.579, c2 = 0.554, c3 = -0.560, c4 = -0.0032, c5 = 0.326, rh = 6 and
σ = 0.3535
- Use records from Costa Rica, Mexico, Nicaragua and El Salvador. Only Mexican earthquakes with
Mw ≥ 6.5 were used.
- Use two site categories:
S = 0
- Rock: 92 records
S = 1
- Soil: 88 records
- Use a Bayesian one-stage regression method (Ordaz et al., 1994) to yield physically possible coefficients.
- Consider tectonic type: subduction or shallow crustal but do not model.
- Find no significant difference between Guerrero (Mexico) and other data.
- Find no significant difference between subduction and shallow crustal data.