关键词: 风险规避, 自有品牌, 转售模式, 代理模式

Abstract: Since its formation, e-commerce has achieved remarkable development results. With the rapid development of e-commerce, the platform, as an important carrier of online selling, has attracted great attention from enterprises. There are two main modes for enterprises to sell products through the platform: one is the reselling mode, that is, the platform buys products from upstream enterprises at the wholesale price and then resells them to consumers at the retail price, such as JD.com, Amazon and so on; the second is the agency mode, that is, upstream enterprises set the retail price and sell products directly to consumers, but need to pay a fixed percentage of revenue to the platform, such as Tmall. For enterprises looking to expand their business through the platform, the choice between two selling modes will be a top priority. Thus, it is necessary to analyze the influence mechanism of different selling mode on enterprise profits.
In the face of such a huge market, more and more platforms choose to introduce store brands and encroach on the market to improve their own profits and bargaining power. Behind the rise in e-commerce and store brand is the increase in consumer purchasing power, which makes consumers more inclined to buy diversified and personalized products and show obvious preference differences for different products, which increases the uncertainty of product demand. At the same time, new brands in the market will intensify market competition. Hence, manufacturers often adopt a risk-averse attitude to cope with volatile markets and this attitude to risk can have a significant impact on the manufacturer's decisions. On the other hand, platforms' store brand strategy as an additional profit channel can also be used as a means to regulate the sales of national brands. Besides, multiple profit sources improve platforms' resilience in the face of demand fluctuations. Hence, this paper assumes that the platform is a risk-neutral enterprise.
This paper considers a supply chain consisting of a manufacturer and a retail platform. Among them, the manufacturer is risk-averse and sells the national brand product on the platform through the reselling mode or agency mode. The retail platform is risk-neutral and can choose to introduce the store brand product. This paper divides all decisions into long-term and short-term decisions. In the long-term decision-making phase, the manufacturer first decides to adopt the reselling mode or the agency mode. The platform then decides whether to introduce the store brand. In the short-term decision-making phase, the manufacturer first decides on the wholesale price or retail price of the national brand. The platform then decides on the retail price of the store brand and the national brand, or only the retail price of the store brand. In each scenario, the market demand for different products is derived according to the consumer's utility estimation of different products, the uncertain demand function of the market is constructed in the form of market demand plus random variables, the utility function of the risk-averse manufacturer is constructed by means-variance theory, and the optimal solution in each scenario is obtained by reverse induction. The main questions discussed are as follows: (1)When should the platform introduce the store brand? (2)Can the manufacturer prevent the platform from introducing the store brand by adopting specific selling modes? (3)How do the manufacturer's risk aversion, consumers' store brand preference, and commission rate affect the decisions of the manufacturer and the platform?
The results show that, for the platform, the reselling mode is conducive to the introduction of the store brand, while the agency mode is only suitable for the introduction of store brand when the commission rate is low. Consumers' preference for the store brand and the manufacturer's risk aversion are harmful for the platform to introduce the store brand. For the manufacturer, the higher the degree of risk aversion, the more likely it is to adopt the agency mode. When the manufacturer tends to be risk-neutral and consumers have quite different preference for different brands, it is difficult for the manufacturer to prevent the platform from introducing the store brand; besides, as long as the commission rate is moderate, the manufacturer can prevent the platform from introducing the store brand by adopting the agency mode. Finally, this paper extends the decision-making analysis when consumers prefer the store brand, and finds that the impact of consumers' store brand preference on game equilibrium is contrary to the basic model.

Key words: risk aversion, store brand, reselling mode, agency mode