Spatial Variability of Soil Organic Carbon Stock in Gurje Subwatershed, Hadiya Zone, Southern Ethiopia

Table 6

Cross-validation indices of the ordinary kriging (OK) interpolation method for SOC and SOCS.

Variables	Depth (cm)	Model	ME	RMSE	MSE	ASE	RMSSE
SOC	0–20	Exponential	0.0766	9.98	−0.0694	10.77	0.95
	20–40	Circular	0.0027	8.80	−0.093	9.14	1.03
SOCS	0–20	Spherical	0.0425	17.40	−0.0752	17.23	0.995
	20–40	Exponential	−0.0617	14.37	−0.0616	12.78	1.038

ME = mean error, MSE = mean standard error, RMSSE = root mean square standard error, RMSE = root mean square error, and ASE = average standard error.