Coupling a Bat Algorithm with XGBoost to Estimate Reference Evapotranspiration in the Arid and Semiarid Regions of China

Figure 4

Scatter plots between the estimated ETo by the three algorithms and the FAO-56 P-M ETo in the testing stage for the Datong station.

(a)

(b)

(c)

(d)

(e)

(f)