Abstract: To solve the problem of cooperative advertising in dual-channel supply chain of complementary products, a Stackelberg master decentralized decision model and a centralized decision model with the manufacturer as the leader considering the spillover effect of complementary products are established. By solving the models, the optimal advertising strategy of the manufacturer, the optimal advertising strategy of the retailer and the optimal sharing rate of cooperative advertising under different decision-making modes are given. Finally, a numerical example is given to verify the relevant conclusions. The results show that the manufacturer's advertisement expenditure on a product is positively correlated with the manufacturer's marginal profits in two channels about the product and its complementary product; the marginal profits of the manufacturer's complementary products in the network channel and retail channel have an impact on the manufacturer's advertisement expenditure on the product, and the incidence depends on the spillover effect coefficient of the product; in addition to the marginal profits of the product and its complementary product in each channel, the manufacturer's cooperative advertising share rate for a product is also related to the nature of the impact of retailer's advertising on the network channel; and the manufacturer's advertisement expenditure, retailer's advertisement expenditure and total profits of the supply chain under centralized decision-making mode are better than decentralized decision-making.

Key words: complementary product, dual-channel supply chain, cooperative advertising, Stackelberg game