It is actually confusing that I got different results with same code and parameters. I downloaded the code that replicating BGG1999 by Ambrogio Cesa-Bianchi from the additional dynare resources. At first time, I ran dynare and got the output (y) and investment (i) were positive. After a few days, I ran again and found that y and i were negative. I tried to change the monetary shock into negative, which meanings rewrite + eM to - eM, then I seemed to get the right results.
The shocks stderr are 0.1 and how i find if the shock is negative or positive. Thanks