Change of GM(1,1,α) model background value on the influences of relative error.

In order to study the influences on model relative error made by the change of grey GM(1,1,α) model background value we analyzed the modeling mechanism and process and put forward the level 2 parameters pack of the model. We focused on the relationship among the change of the background value, the model development coefficient and the grey action by the model's level 2 parameters pack. In theory we concluded the concrete expression among the background value, the development coefficients and the grey action. Then we get the concrete expression between the background value and the relative error and study their relationship on changes. Thus it achieved the result that we can reduce the model relative error through adjust the value of the background. Finally, this conclusion was verified through an example. [ABSTRACT FROM AUTHOR]