Heterogeneity in the effect of green financing constraints on labor investment efficiency: A causal forest approach

This study evaluates the heterogeneous effects of green credit policy on labor investment efficiency. We analyze Chinese listed firms from 2005 to 2020 using the difference-in-differences method and causal forest approach based on the introduction of the 2012 Green Credit Guidelines. Our results show that this policy improves labor investment efficiency in high-polluting firms by reducing over-investment. Causal forest analyses reveal nonlinear and heterogeneous treatment effects, indicating that firms with lower market capitalization, lower liquidity, and higher leverage experience efficiency declines due to financial constraints. Faced with severe agency problems, state-owned enterprises and firms with high employment variability and abnormal investment achieve significant efficiency gains. Finally, despite lower innovation among high-polluting firms following policy implementation, the increased labor investment efficiency mitigates this impact. Overall, the heterogeneity analysis using causal forests highlights the groups most significantly affected by the policy.