几何滞后模型(无限分布滞后模型的特况) y=a+B∑w3X S=0 The long-run response: m=Bw=B/(1-w The mean lag Ml=s=o几何滞后模型（无限分布滞后模型的特况）： The long-run response: The mean lag: 0 s t t s s Y w X    − = = +  /(1 ) s m w w = = −    0 0 s s s s s ML    =  = =  