Network externalities in a vertically differentiated luxury goods market

Abstract

This study examines the impact of network externalities on the market performance of vertically differentiated luxury products. Luxury consumption triggers vanity-driven utility, which decreases due to the snob effect as market share expands. By employing a duopoly model under price competition, we demonstrate that a higher degree of network externalities enhances high-quality product market share, price, and profit while reducing those for low-quality products. The crowding-out of high-quality products on low-quality products becomes more pronounced as network externalities increase. We analyze the effects of quality improvement on equilibrium outcomes, revealing that a moderate reduction in the quality gap benefits social welfare. In contrast, a marginal gap leads to a lose-lose situation for firms. Our study underscores the importance of retaining low-quality products and adopting quality promotion strategies for high-quality products.