One is retrospection on theories of intra-industry trade and empirical study of China's auto industry intra-industry trade. 一是对产业内贸易理论的回顾和对中国汽车产业内贸易的实证研究。
However, China's IIT level doesn't grow rapidly with the trade volume, so it is quite important to research the determinants of China's IIT. 然而,中国的产业内贸易额并没有与其贸易总额保持同步增长,对中国产业内贸易的决定因素的研究显得格外必要。