This paper examines the impact of trade liberalisation on the wage premium using firm level data for Thai manufacturing as the case study. Tariff protection is applied here to represent trade liberalisation, in terms of both nominal and effective tariffs. Output and input tariffs are separately examined to assess nominal protection, while for effective rates of protection (ERP), both a traditional ERP measure and a measure incorporating possible water in tariffs and the effect of FTAs are applied. In addition to tariff protection, the impact of GVCs, considered through trade in parts and components (P&Cs), on the wage premium is investigated in the study. Our results show that firm-specific factors are more crucial in affecting the wage premium than trade liberalisation and participation in global production networks. With trade liberalisation, only input tariffs matter in determining the wage premium while an insignificant relationship is observed when either output tariffs or ERPs are employed to reflect trade liberalisation. Participation in GVCs also has an insignificant impact on the wage premium. Wage-skilled employment decoupling is evident in the study, that is, trade liberalisation and GVCs have a negligible influence on the wage premium but have a significant influence in the case of relatively skilled workers. Trade liberalisation tends to lower demand for skilled workers in response to cheaper imported products, while participation in global production networks encourages more skilled workers.

中文翻译：

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贸易自由化和工资溢价：来自泰国制造业的证据

本文以泰国制造业的企业层面数据作为案例研究，探讨了贸易自由化对工资溢价的影响。这里应用关税保护来代表名义关税和有效关税方面的贸易自由化。分别审查产出和投入关税以评估名义保护，而对于有效保护率（ERP），则采用传统的ERP措施和将可能的水纳入关税和自由贸易协定影响的措施。除了关税保护之外，该研究还调查了通过零部件贸易 (P&C) 考虑的全球价值链对工资溢价的影响。我们的研究结果表明，企业特定因素对工资溢价的影响比贸易自由化和参与全球生产网络更为重要。在贸易自由化的情况下，只有投入关税对确定工资溢价很重要，而当采用产出关税或ERP来反映贸易自由化时，则观察到无关紧要的关系。参与全球价值链对工资溢价也没有显着影响。研究中工资技能就业脱钩现象很明显，即贸易自由化和全球价值链对工资溢价的影响可以忽略不计，但对相对技能工人的影响却很大。贸易自由化往往会降低对技术工人的需求，以应对更便宜的进口产品，而参与全球生产网络则鼓励更多的技术工人。