Classical statistical analyses show significant spatial variability of soil erodibility K values at a scale of small watershed, the variancecoefficientof which is 39.94%.
The weight matrix is replaced by using weight coefficient, and avoids calculating inverse matrix of the error variance matrix.
用计算加权系数的方法代替了原来的计算加权矩阵，从而避免了求解滤波误差方差阵的逆矩阵。
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In comparison with BP method and RBF method, the SVM method is proved to be the best in terms of absolute error, relative error, correlation coefficient and variance.