2023-12-05-国际清算银行-企业异质性_资本错配与最优货币政策_117页_4mb

The paper integrates heterogeneous firms and financial frictions into a New Keynesian model, showing that monetary policy affects capital misallocation, which reduces and optimizes aggregate production. Expansionary shock improves TFP by reallocating capital to high-return firms, creating a misallocation channel.

Central banks face time-inconsistent incentives: they might temporarily surprise the economy with easing to boost TFP, but optimal timeless policy prioritizes price stability, with implications for low-for-longer strategies when constrained by the zero lower bound (ZLB).

The paper contributes methodologically with a new algorithm for tractably solving optimal policies in models, combining finite differences and symbolic differentiation for high-dimensional state spaces.

Empirical support comes from Spanish firm data, confirming that high-MRPK firms respond more strongly to monetary policy, and misallocation decreases, contributing to the rise in TFP.

The model suggests capital misallocation links monetary policy to real effects, complementing other mechanisms like R&D, while allowing for rich dynamics and welfare analyses.

Comparative analysis shows incomplete markets increase the time-inconsistency problem, leading to higher optimal inflation for policymakers, beyond standard markup distortions.