解释灰色系统预测 是什么并举例,可用于数学建模学习
X(1) x(1)(1),x(1)(2),x(1)(3),x(1)(4)
27260,56807,89218,124606
2)对X(1)作紧邻均值生成,令
Z(1)(k) 0.5x(1)(k) 0.5x(1)(k 1)
Z(1) z(1)(1),z(1)(2),z(1)(3),z(1)(4)
27260,42033.5,73012.5,106912
于是,
z(1)(2)1 42033.51 x(0)(2) 29547 B z(1)(3)1 73012.51 ,Y x(0)(3) 32411 (1) 1069121 (0) 35388
z(4)1 x(4)
[a,b] 作最小二乘估计,得 对参数列
(B B) 1B Y 0.089995 a
25790.28
dx(1)设 ax(1) b
dt
由于
可得Gm(1,1)模型的白化方程
dx(1)
0.089995x(1) 25790.28dt
a 0.089995,b 25790.28
其时间响应式为
bb (1)
(k 1) (x(0)(1) )e ak 313834e0.089995k 286574 x
aa
(0)(1)(1)
(k 1) x (k 1) x (k)x
由此得模拟序列 (0) x (0)(1),x (0)(2),x (0)(3),x (0)(4) X
=(27260,29553,32336,35381) 检验:
残差序列为
(0) ( (0)(1), (0)(2), (0)(3), (0)(4))
=(0,-6,75,7)
(0)(1) (0)(2) (0)(3) (0)(4) (0),(0),(0),(0) x(1)x(2)x(3)x(4)
(0,0.0002,0.00231,0.0002) ( 1, 2, 3, 4)