# Compatible Ground Motion Models for South Korea Using Moderate Earthquakes
## 3 Results
### Comparing Residuals
\begin{table}
\begin{tabular}{c c c c c c c} \hline \hline
**GMM** & **2016 Mb** **V5.5** & **2017 Mb** **V5 P** & **Mw** **5.1 F** & **Mw 4.7 A** & **Mw 4.5** & **Sum** \\ \hline AS08 & 1.38 & 2.03 & 1.29 & 1.67 & 2.48 & 8.85 \\ BA08 & 1.70 & 2.11 & 1.67 & 4.25 & 2.40 & 12.13 \\ CB08 & 2.70 & 6.15 & 2.82 & 8.85 & 2.95 & 23.47 \\ CY08 & 1.78 & **0.49** & 2.11 & 2.56 & 8.09 & 15.03 \\ I08 & **1.06** & 1.16 & **0.93** & 1.94 & **1.52** & **6.61** \\ \hline ASK14 & 1.95 & 2.93 & 1.78 & 2.08 & 4.92 & 13.66 \\ BSSA14 & 1.55 & 1.71 & 1.67 & **1.05** & 4.47 & 10.45 \\ CB14 & 1.63 & 2.24 & 1.70 & 1.63 & 4.08 & 11.28 \\ CY14 & 2.17 & 2.77 & 1.80 & 1.69 & 4.99 & 13.42 \\ I14 & **1.50** & **1.26** & **1.22** & 1.58 & **2.29** & **7.85** \\ \hline DASG15 & **0.99** & **1.35** & **1.01** & **1.77** & **1.24** & **6.36** \\ PCZT18 & 2.14 & 2.72 & 1.80 & 1.78 & 1.67 & 10.11 \\ \hline SUM & 20.55 & 26.92 & 20.52 & 28.85 & **16.13** & \\ \hline \hline \end{tabular}  
* \({}^{\text{F}}\) foreshock. A aftershock. P possible induced or triggered earthquake.  
\end{table} 
Table 5: _Score_ for each GMM per earthquake event for SA(T = 0.2 s). Numbers in bold are the lowest in the group. Ends of rows and columns are the summation of the previous metrics for comparison. Figure 10: Distribution of z-scores for spectral acceleration at T = 0.2 s for the subset of NGA-East GMMs applied to the (**a**) Gyeongju, (**b**) 2017 Pohang, (**c**) 2016 Gyeongju foreshock, (**d**) 2018 Pohang aftershock, and (**e**) Ulsan earthquakes. Similar observations are shown in Table 6, which presents the relative residual scores for each GMM compared at SA(T = 1.0 s). However, relative to Table 5, the relative residuals here are much smaller. Again, the NGA-East GMMs and the I08 and I14 GMMs showed some of the lowest scores, but CY08, AS08, and all NGA-West2 GMMs did well, all things considered. Interestingly, all GMMs did well for the 2016 Gyeongju main shock at SA(T = 1.0 s). This is in contrast to Table 5, showing better performance for the smallest earthquake, which also happened to be the farthest from most seismic recoding stations, the 2016 Ulsan earthquake. Table 7 presents the relative residual scores for each GMM compared at SA(T = 0.02 s). Surprisingly, the NGA-East GMMs did not score as well at the stiffer range of ground shaking. Notable performances were observed for both the I08/I14 and AS08/ASK14 GMMs. All GMMs considered tended to do well for both Gyeongju events. Table 8 presents the relative residual scores for each GMM compared at SA(T = 10.0 s). Interestingly, the overall _Scores_ are not as large as expected as the accuracy of the GMMs might not match at such low levels of shaking. For long periods of shaking, the I08/I14 \begin{table}
\begin{tabular}{c c c c c c c} \hline
**GMM** & **2016 M\({}_{W}\) 5.5** & **2017 M\({}_{W}\) 5.5 P** & **M\({}_{W}\) 5.1 F** & **M\({}_{W}\) 4.7 A** & **M\({}_{W}\) 4.5** & **Sum** \\ \hline AS08 & 1.17 & 2.43 & 2.54 & 1.70 & 1.16 & 8.00 \\ BA08 & 1.43 & 3.57 & 3.13 & 3.27 & 1.53 & 12.93 \\ CB08 & 1.54 & 5.92 & 3.23 & 4.19 & 1.53 & 16.41 \\ CY08 & 1.22 & **0.48** & 2.52 & **1.34** & 1.49 & **7.05** \\ I08 & **0.72** & 2.11 & **1.66** & 2.03 & **0.93** & 7.45 \\ \hline ASK14 & 1.23 & **1.29** & 1.42 & 1.83 & 3.30 & 9.07 \\ BSSA14 & 1.03 & 1.42 & 1.31 & 1.38 & 2.86 & 8.00 \\ CB14 & **0.96** & 2.54 & 1.42 & 1.59 & 2.67 & 9.18 \\ CY14 & 0.97 & 1.42 & 1.20 & **1.28** & 3.47 & 8.34 \\ I14 & 1.72 & 1.40 & **1.31** & 2.04 & **1.84** & **8.31** \\ \hline DASG15 & **0.93** & **2.33** & **1.82** & 1.32 & **0.95** & **7.35** \\ PCZT18 & 1.18 & 2.10 & 1.97 & 0.62 & 1.63 & 7.50 \\ \hline SUM & **14.10** & 27.01 & 23.53 & 22.59 & 23.36 & \\ \hline \end{tabular} \({}^{\rm F}\) foreshock. \({}^{\rm A}\) aftershock. \({}^{\rm F}\) possible induced or triggered earthquake.  
\end{table} 
Table 6: _Score_ for each GMM per earthquake event for SA(T = 1.0 s). Numbers in bold are the lowest in the group. Ends of rows and columns are the summation of the previous metrics for comparison.