6-11 What determines whether an Equation is Identified or not? We could have three possible situations 1. An equation is unidentified like(12)or(13) we cannot get the structural coefficients from the reduced form estimates 2. An equation is exactly identified eg.(4)or(5) can get unique structural form coefficient estimates 3. An equation is over-identified Example given later More than one set of structura coefficients could be obtained from the reduced form C Chris brooks2002,陈磊204© Chris Brooks 2002, 陈磊 2004 6-11 We could have three possible situations: 1. An equation is unidentified · like (12) or (13) · we cannot get the structural coefficients from the reduced form estimates 2. An equation is exactly identified · e.g. (4) or (5) · can get unique structural form coefficient estimates 3. An equation is over-identified · Example given later · More than one set of structural coefficients could be obtained from the reduced form. What Determines whether an Equation is Identified or not?