Table 3 Sunshine duration-based annual regression results and their statistical evaluation
From: Global solar radiation estimation from commonly available meteorological data for Bangladesh
Model no. | Model type | Equations | \(R^{2}\) | MBE | MPE | RMSE | MARE | t stat |
|---|---|---|---|---|---|---|---|---|
1 | Linear | \(H{/}H_0 = 0.4256 (S{/}S_0) + 0.2199\) | 0.8888 | 0.0183 | 0.3446 | 0.2404 | 0.3446 | 0.2538 |
2 | Quad. | \(H{/}H_0 = 0.749(S{/}S_0)^2 - 0.3752(S{/}S_0) + 0.417\) | 0.8920 | 0.0216 | 0.3276 | 0.2369 | 0.0440 | 0.3049 |
3 | Cubic | \(H{/}H_0 = 3.1987(S{/}S_0)^3 - 4.4223(S{/}S_0)^2 + 2.3158(S{/}S_0) - 0.0306\) | 0.8899 | 0.0231 | 0.3246 | 0.2393 | 0.0471 | 0.3226 |
4 | Expo. | \(H{/}H_0 = 0.2673 \exp [0.9422(S/S_0)]\) | 0.8913 | 0.0261 | 0.1707 | 0.2376 | 0.0494 | 0.3673 |
5 | Log. | \(H{/}H_0 = 0.2152\,\hbox {ln}(S{/}S_0) + 0.5916\) | 0.8729 | 0.0153 | 0.3850 | 0.2570 | 0.0560 | 0.1981 |
6 | Power | \(H{/}H_0 = 0.6093(S{/}S_0)^{0.478}\) | 0.8804 | 0.0233 | 0.1998 | 0.2493 | 0.0537 | 0.3125 |