短語詞組短語approximation error upper bound 逼近偏差上限finite difference approximation error 有限差分誤差Approximation Error Variance 逼近誤差方差the optimal approximation error 最優(yōu)逼近誤差system approximation error 系統(tǒng)逼近誤差linear approximation error 直線逼近誤差approximation error convergence 逼近誤差收歛order of best approximation error 最佳逼近的堦model approximation error upper bound 模型預(yù)測誤差上限 返回 approximation error