Research Article
Research on the Concentration Prediction of Nitrogen in Red Tide Based on an Optimal Grey Verhulst Model
Table 4
Accuracy comparison of GVM, BPGVM, and BRGVM models.
| Measured raw data | GVM | BPGVM | BRGVM | Prediction value | The relative error (%) | Prediction value | The relative error (%) | Prediction value | The relative error (%) |
| 30 | 30 | 0 | 30 | 0 | 29.1 | −2.9 | 33 | 36.5 | 10.6 | 36.1 | 9.2 | 35.1 | 6.3 | 37 | 43.2 | 16.9 | 42.7 | 15.3 | 41.7 | 12.5 | 45 | 50.5 | 12.1 | 49.6 | 10.2 | 48.5 | 7.9 | 55 | 57.8 | 5.1 | 56.7 | 3.1 | 55.6 | 1.2 | 65 | 65.1 | 0.2 | 63.7 | −1.9 | 62.7 | −3.5 | 72 | 72.1 | 0.09 | 70.4 | −2.2 | 69.4 | −3.6 | 76 | 78.4 | 3.3 | 76.5 | 0.7 | 75.5 | 0.0 |
| Average relative error (%) | 6.9 | 5.3 | 4.8 |
| Extrapolation values | 84.2 | 82.0 | 81.0 |
|
|