Estimating topsoil texture fractions by digital soil mapping - a response to the long outdated soil map in the Philippines

Table 7 Cross validation of OK, SK, and UK applying exponential, Gaussian, and spherical variogram models applied to Silt texture fraction

Spatial Interpolation	Variogram model	MAE	RMSE	R²
OK
	exponential	0.144	0.230	0.8868
	Gaussian	0.279	0.375	0.6835
	spherical	0.178	0.259	0.8607
SK
	exponential	0.144	0.230	0.8864
	Gaussian	0.278	0.375	0.6822
	spherical	0.177	0.259	0.8601
UK – Forward
	exponential	0.141	0.221	0.8926
	Gaussian	0.268	0.345	0.7308
	spherical	0.172	0.247	0.8689
UK – Backward
	exponential	0.141	0.221	0.8929
	Gaussian	0.267	0.345	0.7311
	spherical	0.172	0.246	0.8691
UK – Stepwise
	exponential	0.141	0.221	0.8926
	Gaussian	0.268	0.344	0.7324
	spherical	0.172	0.246	0.8690

ISSN: 2468-2039