قیمت های انعطاف پذیر، اختلاف بازار کار و واکنش اشتغال به تلاطم های تکنولوژی

Recent empirical evidence establishes that a positive technology shock leads to a decline in labor inputs. Standard RBC models fails to replicate this stylized fact, while recent papers show that augmenting the model with implementation lags, or habit for Recent empirical evidence establishes that a positive technology shock leads to a decline in labor inputs. Standard RBC models fails to replicate this stylized fact, while recent papers show that augmenting the model with implementation lags, or habit formation, or shock persistence in growth rates among others accounts for this fact. In this paper, we show that a standard flexible price model with labor market frictions that allows hiring costs to depend on technology shocks may also lead to the same negative impact on labor inputs. Labor market frictions are therefore able to account for the fall in labor inputs. However, the elasticity of hiring costs to technology shocks is large, suggesting that additional extensions to the model are needed.

Galí (1999) and a number of subsequent studies show that technology shocks have a contractionary effect on employment.2 In a standard flexible price model, a positive technology shock increases employment since output rises on impact and additional labor inputs are required to keep pace with higher technology. This paper investigates whether a standard flexible price model enriched with labor market frictions is able to generate the negative response of employment to a technology shock.3 In order to investigate this issue, we set up a standard flexible price model that allows, but does not require, labor market frictions to generate a negative response of employment to technology shocks. We estimate the model using Bayesian methods and find that the data strongly prefer the version of the model in which labor market frictions generate a negative response of employment to technology shocks.

Recent empirical evidence led by Galí (1999) and supported by several subsequent studies finds that a positive technology shock leads to a decline in labor inputs. This paper uses Bayesian methods to establish that labor market frictions enable a standard flexible price model to match this stylized fact. We believe that this finding clearly underlines the importance of labor market frictions to accurately characterize the dynamics of labor inputs to technology shocks in the context of estimated general equilibrium models. The model puts forward some interesting avenues for future research. First, labor market frictions introduce flows in and out of employment. It would be interesting to establish the contribution of each flow to the fall in employment. This task, however, would prove to be non-trivial because it requires introducing endogenous job destruction. Second, it also would be interesting to enrich the model with nominal price rigidities that Galí (1999) identifies as an alternative mechanism to rationalize the fall in employment in the aftermath of a positive technology shock. In this way, it would be possible to establish to what extent labor market frictions and nominal price rigidities compete to account for the observed stylized fact. These investigations offer avenues for future research.