# Problem with ST SIM

Hello everyone. I have the following model:

``````var
y
c
i
x
r
w
n
a
z
dz
;

varexo
eps_a
;

parameters
alpha
teta
gamma
sigma
varphi
gammai
rhoa
;

alpha   =   0.4;
gamma   =   0.4;
teta    =   1.2;
sigma   =   2;
varphi  =   4;
gammai  =   0.2;
rhoa    =   0.85;

model (linear) ;

#gammax =   alpha^2 ;
#gammac =   1 - gammai - gammax ;

y   =   gammac*c + gammai*i + gammax*x ;

w   =   y - n ;

w   =   sigma*c + varphi*n ;

c   =   c(+1) - (1/sigma)*r ;

z   =   z(-1) + dz ;

dz  =   gamma*i ;

y   =   a + z(-1) + (1-alpha)*n + alpha*x ;

x   =   n + (1/(1-alpha))*a ;

r   =   sigma*(c(+1) - c) ;

a   =   rhoa*a(-1) + eps_a ;

end;

check;

shocks ;
var eps_a ; stderr 1;
end;

stoch_simul(irf=80);
``````

and I got the following error:

Error using print_info
The generalized Schur (QZ) decomposition failed. For more information, see the documentation for Lapack function dgges: info=30, n=3. You can also run model_diagnostics to get more information on what may cause this problem.

Can you help me to solve the issue?

You have

``````    c   =   c(+1) - (1/sigma)*r ;
r   =   sigma*(c(+1) - c) ;
``````

These two equations are identical.

So I have another question: in a RBC model without stock of capital, how can I find the real interest rate?

If there is no intertemporal asset, there is no interest rate.

Thank you very much!