Negative steady-state consumption in NK-DSGE model with search and matching (Dynare 6.4)

Hello everyone,

I am working on a small-open NK-DSGE model with labor market search and matching frictions (a “NK-SME” extension). The model runs and converges, but the steady-state value of consumption (C) is negative, even though all other steady-state variables look reasonable.

I’ve already written a robust steady-state file that solves for theta, mc, w, and Rk through nested fixed-point iterations. The code runs successfully in Dynare 6.4, using my own modelo_final_steadystate.m.

Here are the steady-state results (variables are all explained on the files attached):
STEADY-STATE RESULTS:
C -0.850369
I 4.61573e-05
K 0.00184629
Y 0.149677
w 0.00684574
Rk 0.704108
R 1.67911
pi 0.587688
mc 0.0263191
n 0.99347
u 0.00652974
v 0.123389
theta 18.8965
m 0.0198694
f 3.04291
q 0.16103
J 0.0621002
Pi 0.145737
A 1.2
X 1
S 1

All static residuals are zero, and the model runs smoothly with stoch_simul(order=1, irf=20). However, despite consistent FOCs and resource constraints (Y = C + I + S), consumption remains negative. I suspect the issue may come from:

  • either a scaling or calibration inconsistency between the output and real wage equations,

  • or possibly the definition of marginal cost and output normalization.

Question:
What could be driving negative steady-state consumption in this type of model? Could it be a normalization error (e.g., scaling of mc or wage), or a deeper issue in the calibration/production side? Any guidance on how to fix or diagnose this would be greatly appreciated.

I’ve attached the .mod and steady-state .m files below for reference.

Thanks in advance,
César M. Martínez

modelo_final.mod (3.0 KB)

modelo_final_steadystate.m (7.7 KB)

There is something odd with your model. Why is there an inflation rate appearing in the return for capital? In your steady state file you you start by assuming that inflation is 1 in steady state, but then you compute its steady state endogenously. That looks inconsistent.