Consider the following New Keynesian DSGE Model with standard notation:
$\pi_t = \kappa y_t + \gamma_f \mathbb{E}_t[\pi_{t+1}] + \gamma_b \pi_{t-1},$
$y_t = \mathbb{E}_t[y_{t+1}] - \frac{1}{\sigma}(i_t - \mathbb{E}_t[\pi_{t+1}] - r_t^n),$
$i_t = \rho + \phi_{\pi}\pi_t + \phi_y y_t + v_t.$
How would one go about deriving sufficient conditions for the existence of a unique non-explosive equilibrium under rational expectations? I'm familiar with a method for doing this when $\gamma_b=0$ (such that the Phillips curve is non-hybrid), but I have been unable to find any litterature on the case of a hybrid Phiilips curve.
Any input is appreciated very much, thanks!
