Y=1.181614X3-510.8555 (48.90096) (-3.201293)
2y?3R2y?3=0.99625 R=0.995834 F=2391.304 DW=3.01082
再分别对Y与X1、X2,Y与X1,X3进行回归分析: Y与X1、X2回归分析结果:
Y=0.678232X1-13.74984X2+2103.152 (36.30401) (-0.48099) (0.765402)
2y?1?2R2y?1?2=0.998698 R F=3067.705 DW=0.934588 ?0.998372Y与X1、X3回归分析结果:
Y=0.528176X1+0.251291X3+402.7872 (4.249616) (1.145463) (1.961719)
R2y?1?3=0.998849 R2y?1?3=0.998561 F=3471.004 DW=1.695322
综合回归分析的相关系数,如下:
R2?0.99888 R21-2=0.790207 R2y?2=0.784162 R2y?1?2=0.998698
R2y?1=0.99866 R21-3=0.99581 R2y?3=0.99625 R2y?1?3=0.998849 对相关系数分析后,可知:X1与X2、Y与X2的相关程度都相对较低,即拟合优度较低。在Y与X2的相关回归模型中引入变量X1或X3都能大幅度的提高拟合优度,说明X1,X3与Y的相关程度较高,因此,去除变量X2。 去除变量X2得:
Y=0.528176X1+0.251291X3+402.7872