Cooperation Partnerships in Livestream E-Commerce: Optimal Selection for Brand Manufacturers

Live-streaming commerce has become a critical information channel through which consumers evaluate products and make purchase decisions, yet brand manufacturers face substantial uncertainty when selecting live-streaming partners. This study investigates how streamer influence and consumer sensitivity to live-streaming service quality jointly shape optimal cooperation structures in platform-based commerce. We develop a game-theoretic decision framework comparing three cooperation modes—Nash negotiation, manufacturer-led, and streamer-led, and derive closed-form equilibria for pricing, service quality and profit allocation. The results show that manufacturer-led cooperation consistently maximizes brand profit by preserving incentives for service quality provision, while streamer-led cooperation can reduce overall efficiency when dominant streamers lack motivation to improve service quality. Using live-stream sales data from the Douyin (TikTok) platform covering multiple streamer tiers and two cosmetic brands, we empirically validate the model's predictions. The findings contribute to research on information processing and incentive alignment in platform-based live-streaming commerce.