Dear All:
Attached is my code trying to replicating the paper "Can News Drive Up Business Cycles" by Jaimovich and Rebelo. I log-linearze the system by hand. Since they don't specify the functional form of investment and utilization adjustment cost, I use simple quadratic setting. The parameters are named following traditions. I checked the steady states and the co-efficients in the linearized system, and they seem to be right, except some rounding errors (at the magnitude of 1e-15).
However, the generated IRFs are quite different from what JR get in the paper. I looked into details. The most problematic part of my code is the NEGATIVE eigenvlue in the system, which looks weird. The transition matrix shows huge response to technology shocks.
If you can find any bugs in my code, I really appreciate you help..