15.2 Real-Business-Cycle Theory's Explanation to Important Economic Variables o Explanations to the fluctuations of output, consumption investment o Use simplified"Ramsey-Cass-Coopmans"model to analyze 2 Object functions max EU=El2Bu(CtI .tY=f(K)=C+l,K=l+()Kt u>0,u”<0;f>0,f"<0 友学经济学院
15.2 Real-Business-Cycle Theory’s Explanation to Important Economic Variables ❖ Explanations to the fluctuations of output, consumption & investment Use simplified “Ramsey-Cass-Coopmans” model to analyze ： ❖Object functions： t t t t t 1 t t t i 0 i t t s.t.Y f(K ) C I ,K I (1 )K max E U E [ u(C )] = = + = + − = + = u 0,u 0;f 0,f 0
15.2 Real-Business-Cycle Theory's Explanation to Important Economic Variables .fo.c: u(C1)=B·E{u'(Ct)[f(K)+(1-o) & TVC limelBTu' (ChiK+=0 友学经济学院
15.2 Real-Business-Cycle Theory’s Explanation to Important Economic Variables ❖ F.O.C： ❖ TVC： u'(C ) E {u'(C ) [f'(K ) (1 )]} t = t t+1 t+1 + − limE [ u'(Ct i )Kt i 1 ] 0 t i t i + + + = + →