Sztywność płac nominalnych w modelach DSGE małej skali. Analiza empiryczna dla Polski

The paper examines the empirical importance of the assumption of "sticky wages" in small­‑scale dynamic stochastic general equilibrium (DSGE) models estimated for the Polish economy. The evaluation is based on a Bayesian comparison between the baseline "sticky price" model and a model of price and wage rigidities. The comparison includes extensions of these models to account for the case of price and wage indexation. The analysis consists of two steps. In the first step, each model is estimated using quarterly data for the Polish economy from 1995 to 2011. In the second step, the "marginal data density" is calculated for each model and so‑called Bayes factors are obtained. The results suggest that the best fit to the sample is observed in the case of the model with wage and price rigidities. Moreover, price and wage indexation mechanisms seem to have an insignificant impact on how the model fits the data, the author says. A comparison of impulse response functions shows that there are significant differences between the baseline model and the model with sticky prices and wages. Moreover, the estimates of structural parameters were strongly affected by the introduction of wage rigidities, the author says.