Kobayashi and Midorikawa (1982)

Ground-motion model is:
$logSv0(T ) = a(T)(logM0 - c) - b(T )logX + d where a(T ) = a1 + a2log T { 2 and: b(T )) = b1(logT ) + b2logT + b3 for: 0.1 ≤ T ≤ 0.3s b4 - b5logT for: 0.3 ≤ T ≤ 5s$
Response parameter is velocity for 5% damping.
Magnitudes converted to seismic moment, M₀, by using empirical formula.
Observed surface spectra divided by amplification over bedrock (assumed to have shear-wave velocity of 3km∕s), calculated for each of the 9 sites.
Note equation not for near field because earthquake is not a point source.