Economic and Environmental Geology

Table. 2.

Table. 2.

Correlation coefficient (r) and root mean-squared error (RMSE) between the measured and predicted values using the validation data (n=30 determined by ICE-AES) at different sampling densities for training (n=30 to 107 determined by ICP-AES) by each model: OK (ordinary kriging), OCK (ordinary co-kriging), GMM (Gaussian mixture model)

As Pb
Sampling density Prediction method r RMSE rGMM ‒ rgeost.* RMSEGMM‒RMSEgeost.** Sampling density Prediction method r RMSE rGMM ‒ rgeost.* RMSEGMM‒RMSEgeost.**
30 OK 0.59 0.28 0.27 -0.05 30 OK 0.46 0.37 0.46 -0.2
OCK 0.64 0.26 0.22 -0.03 OCK 0.6 0.5 0.32 -0.33
GMM 0.86 0.23 GMM 0.92 0.17
49 OK 0.61 0.28 0.31 -0.11 49 OK 0.52 0.34 0.39 -0.17
OCK 0.66 0.26 0.26 -0.09 OCK 0.61 0.31 0.3 -0.14
GMM 0.92 0.17 GMM 0.91 0.17
61 OK 0.67 0.25 0.26 -0.09 61 OK 0.54 0.33 0.43 -0.25
OCK 0.72 0.24 0.21 -0.08 OCK 0.62 0.31 0.35 -0.23
GMM 0.93 0.16 GMM 0.97 0.08
76 OK 0.73 0.24 0.11 -0.01 76 OK 0.58 0.32 0.38 -0.2
OCK 0.76 0.22 0.08 0.01 OCK 0.66 0.29 0.3 -0.17
GMM 0.84 0.23 GMM 0.96 0.12
91 OK 0.73 0.24 0.22 -0.1 91 OK 0.61 0.31 0.37 -0.23
OCK 0.77 0.22 0.18 -0.08 OCK 0.68 0.29 0.3 -0.21
GMM 0.95 0.14 GMM 0.98 0.08
107 OK 0.75 0.23 0.21 -0.1 107 OK 0.62 0.31 0.35 -0.2
OCK 0.79 0.21 0.17 -0.08 OCK 0.68 0.28 0.29 -0.17
GMM 0.96 0.13 GMM 0.97 0.11

*rGMM ‒ rgeost.: performance comparison (r) between GMM and geostatistical approach (OK or OCK);

**RMSEGMM ‒RMSEgeost: performance comparison (RMSE) between GMM and geostatistical approach (OK or OCK).

Econ. Environ. Geol. 2022;55:353-66 https://doi.org/10.9719/EEG.2022.55.4.353
© 2022 Econ. Environ. Geol.