推导基于原序列和一阶生成序列的扩展GM(1,M)模型无偏解法,并给出灰色模型的最大预测时间尺度计算式。新建立的模型具有数值稳定、建模客观以及无偏性的特点。应用实例表明,对于小湾水电站高边坡工程,无偏扩展GM(1,M)预测精度及可靠性均优于无偏GM(1,1)和扩展GM(1,M)。
An unbiased estimation method based on original series and accumulated series for extended grey model (E-GM) is developed, and the formula is proposed for calculating maximum predictable time scale of grey model. Unbiased extended GM (UE-GM) has the characteristics of numerical stability, modeling objectivity and unbiased property. The steep slope engineering of Xiaowan Hydropower Station is studied as a case. The results show that the UE-GM (1, M) model is better than the U-GM (1, 1 ) and the E-GM (1, M) models in precision and reliability.