Quality Certification and Coopetition in Live-Streaming E-Commerce: A Differential Game with Consumer Reference Effects

With the rapid growth of live-streaming e-commerce, product quality information asymmetry and intensified brand competition pose challenges for platform quality governance and inter-firm innovation. This study develops a platform-based supply chain with one live-streaming platform and two competing brand manufacturers. A differential game integrates quality certification, independent development, and coordinated development to examine strategic decisions and economic performance. Results show that quality certification increases manufacturers’ quality investment and platform marketing effort, thereby improving brand reputation, prices, and demand. Its benefits depend on competitive intensity and the reference quality effect. Stronger reference quality effects favor coordinated development, whereas intensified competition strengthens the advantage of independent development; quality investment and coordination and integration costs further shape manufacturers’ choices. The platform’s certification decision reflects a trade-off between fixed certification costs and incremental benefits and is influenced by manufacturers’ coopetition strategies. Quality certification and coordinated development also exhibit significant synergy, generating higher firm profits, supply chain profits, consumer surplus, and social welfare under appropriate conditions. These findings provide decision support for platforms and manufacturers in optimizing quality certification, collaborative R&D, and platform-based quality governance.