贸易政策不确定性的企业出口效应：实证和理论分析

The Firms Exports Effect of Trade Policy Uncertainty: An Empirical and Theoretical Analysis

摘要:

贸易政策不确定性已成为全球经济增长的重要风险，不同类型企业需结合自身风险偏好和经营特点动态调整行为决策，增强出口韧性。通过内生TVP-VAR模型、数理推导、DSGE模型对贸易政策不确定性的出口效应进行量化分析与理论模拟，研究结果表明：第一，多维脉冲响应评价指标下，贸易政策不确定性对企业出口产生负向影响，不同所有制类型企业出口表征出差异化响应特征，外资 (独资) 企业受贸易政策不确定性的影响显著，国有企业受贸易政策不确定性的冲击干扰较弱。第二，当企业类型为风险厌恶型时，汇率波动和关税改变引发的贸易政策不确定性越大，企业进入市场的概率越小、退出市场的概率越大，企业出口规模越小。第三，以进口关税和出口补贴为代表的贸易政策不确定性会对企业出口产生负向影响，且进口关税对企业出口的干扰更大。本文使用的内生TVP-VAR模型克服了传统VAR系列模型对冲击外生性的约束条件，提升了模型对现实经济的解释力度，精准刻画出贸易政策不确定性冲击与企业出口响应之间的时变关联。同时，本文通过严谨的数理推导，揭示出风险厌恶型企业面对汇率波动与关税变动时进入概率下降、退出概率上升的出口规模收缩微观传递链条。此外，本文基于DSGE模型的理论模拟，加深了各界对贸易政策不确定性企业出口效应相关问题的理解。

Abstract:

Trade policy uncertainty has become an important risk for global economic growth. Different types of enterprises need to dynamically adjust behavioral decisions based on their own risk preferences and operating characteristics to enhance export resilience. This article first uses exchange rate volatility and tariff changes as the starting point to mathematically deduce the correlation between trade policy uncertainty and corporate exports, and further conducts quantitative analysis and theoretical simulation of the export effects of trade policy uncertainty through the endogenous TVP-VAR model, theoretical derivation and DSGE model. The research results show that: first, under the multi-dimensional impulse response evaluation index, trade policy uncertainty has a negative impact on corporate exports. The exports of companies with different ownership types show differentiated response characteristics. Foreign-owned (solely-owned) companies are significantly affected by trade policy uncertainty, while state-owned enterprises are less affected by the impact of trade policy uncertainty. Second, when the enterprise type is risk averse, the greater the trade policy uncertainty caused by exchange rate volatility and tariff changes, the smaller the probability of the enterprise entering the market, the greater the probability of exiting the market, and the smaller the enterprise''s export scale. Third, trade policy uncertainty represented by import tariffs and export subsidies will have a negative impact on corporate exports, and import tariffs will have greater interference with corporate exports. The endogenous TVP-VAR model employed in this study overcomes the strong exogeneity constraints of traditional VAR series models, enhancing the model''s explanatory power for real-world economies and accurately capturing the time-varying relationship between trade policy uncertainty shocks and corporate export responses. Through rigorous mathematical derivation, the paper reveals the micro-level transmission chain of export scale contraction, where risk-averse firms exhibit reduced entry probabilities and increased exit probabilities when faced with exchange rate fluctuations and tariff changes. Additionally, based on theoretical simulations from the DSGE model, the study deepens understanding of issues related to corporate export effects under trade policy uncertainty.