This study examines how reforming the rules of origin (RoOs) in one preference regime affects trade under each tariff regime. To do this, we focus on Japan’s imports of apparel products from Cambodia and Myanmar during the 2013–2018 period. In these trade flows, two preference regimes are available in addition to a most favored nation regime. We find that the relaxation of RoOs in one regime in 2015 increased imports under that regime but decreased imports under the other regimes. As a result, total imports increased by approximately 80%.

中文翻译：

---

多种优惠制度和原产地规则

本研究探讨了在一个优惠制度中改革原产地规则 (RoO) 如何影响每种关税制度下的贸易。为此，我们重点关注 2013-2018 年期间日本从柬埔寨和缅甸进口的服装产品。在这些贸易流中，除了最惠国制度外，还有两种优惠制度可用。我们发现，2015 年在一个制度下放宽原产地规则增加了该制度下的进口，但减少了其他制度下的进口。因此，进口总额增加了约 80%。