The study analyzed wage gaps and factors influencing them in primary firms and subcontractors. They found that the wage gap between primary firms and subcontractors is mainly influenced by factors like company size, education level, and industry type. Additionally, factors like company performance and labor productivity also play a role in determining wage gaps. The study suggests that to reduce wage gaps between primary firms and subcontractors, both supply-side factors like differences in human capital and demand-side factors like company performance need to be considered together.