Meteorological Drought Monitoring Based on Satellite CHIRPS Product over Gamo Zone, Southern Ethiopia

Table 3

Statistical measures of performance used for analysis based on continuous metrics.

Statistic	Formula	Range	Best value
Root mean square error (RMSE)		−∞ to ∞	0
Percent of bias (PBIAS)		−∞ to ∞	0
Mean absolute error		0 to ∞	0
Nash–Sutcliffe efficiency coefficient		−∞ to ∞	1
Bias		0 to ∞	1
Correlation coefficient (R)		−1 to 1	1

Note. Rg, Rs, , and N represent rainfall at the rain gauging station, chirping satellite rainfall, the mean of observed rainfall, and the number of data pairs compared, respectively.