显性大国效应与隐性大国效应的发现与证实——基于中国原木、锯材进口贸易的实证研究

The Discovery and Confirmation of Dominant Large Country Effect and Implicit Large Country Effect——Empirical Study Based on China’s Log and Sawn Wood Imports

中国作为原木、锯材进口贸易第一大国,是否存在大国效应?文章基于中国2001-2020年原木、锯材进口数据,通过构建向量自回归系列模型,借助Spearman等级相关系数、Matlab函数拟合与边际价格估算,动态研究中国原木、锯材进口贸易的显性大国效应、隐性大国效应、大国效应的作用区间及影响程度。结果表明:(1)中国原木进口贸易的显性大国效应显著,虽然中国锯材进口贸易的显性大国效应具有阶段性与非连续性,整体并不显著,但其隐性大国效应显著,即中国原木、锯材进口贸易均存在大国效应。(2)随着中国原木、锯材进口量的增加,相应产品国际价格的上涨速度也会逐渐放缓。当中国原木月度进口量分别在179.15~250.00万立方米、250.00~300.00万立方米、300.00~350.00万立方米、350.00~704.91万立方米时,价格弹性分别为0.81、0.52、0.24、0.07;当中国锯材月度进口量分别在40.32~60.00万立方米、60.00~100.00万立方米、100.00~265.68万立方米时,价格弹性分别为1.16、0.18、0.04。(3)受大国效应影响,中国原木月度进口量由179.15万立方米增长至704.91万立方米时,由于价格随之上涨会造成约8.21亿美元的额外损失;中国锯材月度进口量由40.32万立方米增长至265.68万立方米时,由于价格随之上涨会造成约7.74亿美元的额外损失。因此,应保持相对平稳的进口规模,通过统筹国内外原木和锯材来源、提升国际市场势力等措施来弱化大国效应的负面影响。

China is the largest country of log and sawn wood imports, is there large country effect? Based on China’s log and sawn wood imports data from 2010 to 2020, the Vector Auto Regression series models, Spearman rank correlation coefficient, function fitting by Matlab and marginal price estimation were used to study the existence of dominant large country effect and implicit large country effect,and estimate the influence scope and degree of large country effect. The results showed that:(1)Dominant large country effect of China’s log imports was significant. Although dominant large country effect of China’s sawn wood imports was phased and discontinuous, and was not significant in the whole sample interval, implicit large country effect was significant. That is, China’s log and sawn wood imports had large country effect.(2)With the increase of China’s log and sawn wood imports, the increase rate of international log and sawn wood prices gradually slowed down. When China’s monthly log imports were in the range of 1.79~2.50, 2.50~3.00, 3.00~3.50 and 3.50 ~7.05 million cubic meters, the corresponding price elasticity of each range were 0.81, 0.52, 0.24 and 0.07, respectively. When China’s monthly sawn wood imports was in the range of 0.40~0.60, 0.60~1.00 and 1.00~2.66 million cubic meters, the corresponding price elasticity of each range were 1.16, 0.18 and 0.04, respectively.(3)Affected by large country effect, China’s log imports increased from 1.79 million cubic meters to 7.05 million cubic meters per month, which would cause a loss of about 821 million US dollars. And China’s sawn wood imports increased from 0.40 million cubic meters to 2.66 million cubic meters per month, which would cause a loss of about 774 million US dollars. Therefore, the import scale of China’s log and sawn wood should be maintained a relatively stable. In addition, the impact of large country effect should be weakened by measures such as coordinating domestic and foreign log and sawn wood sources and enhancing international market power.