Optimizes Grey Derivative of Unequal Interval Grey GM(1,1) Model

Based on the optimizes grey derivative arithmetic,unequal interval grey model GM(1,1)is improved which grey derivative is substituted by weighted average of forward difference quotient and backward difference quotient,and giving the formula of weighted coefficient.The new model of unequal interval sequence is estabhshed by optimize parameter step by step.The application example shows that the new model has highly precision.