主权债务规模动态调整机制研究

The Dynamic Adjustment of the Scale of Sovereign Debt

文章利用2000—2011年121个国家的相关数据，基于非线性动态模型，通过将主权债务规模最优水平和调整速度内生化，实证考察了主权债务规模的调整机制。研究结果表明，主权债务规模存在最优水平，但在整体上表现为过度负债。由于调整成本和经济结构等的阻碍，主权债务规模无法始终维持在最优水平上，而是呈现出一个渐进而缓慢的动态调整过程。通过进一步的检验发现，调整速度与经济增长、经济规模和偏离最优规模水平的程度均显著正相关，并且会随着时间和国家特征的变化而变化。因此，处于不同发展阶段的不同国家要根据其自身特征来优化调整主权债务规模，以规避过度负债所产生的风险。

This paper studies the dynamic adjustment mechanism of the scale of sovereign debt with a nonlinear dynamic model covering121 countries over the year from 2000 to 2011 by making the optimal level and adjustment speed of sovereign debt size endogenous. The results show that the optimal level of sovereign debt size exists,but the actual size is excessive on the whole. Due to the obstruction of adjustment costs and economic structure,the size of sovereign debt can't always be maintained at the optimal level,but appears a gradual and slow dynamic adjustment process. The average adjustment speed is 0. 084. Through further examination we find that the adjustment speed is significantly positively correlated with economic growth,the size of economy and the distance between optimal and observed scale level,and it changes according to time and country characteristics. Therefore,in order to avoid risks from excessive debt,different countries which are at different development stages should adjust and optimize the size of sover-eign debt in accordance with their own situations.