基于网络外部性的规模收益与产品差异化

Return of scale and product differentiation with network externality

通过构造一个纵向产品差异化的两阶段模型(先决定产品质量再决定产量),研究了当产品具有网络外部性特征时,其规模收益特征对企业的产品质量差异度、利润、产品价格和需求等因素的影响.然后对产品的规模收益递增和递减两种情况作了比较分析并得出相应的结论.研究表明,当不考虑网络外部性时递减规模收益假设下产品的质量(不论是高质量还是低质量)都要低于递增规模收益情形;而考虑网络外部性时递减规模收益假设下的高质量要远大于递增规模收益假设下的质量;递减规模收益假设下的市场需求都要低于递增规模收益假设下的市场需求,这与产品是否具有网络外部性特征无关.

In a vertical product differentiation model, firms first simultaneously choose their qualities, and then choose output. We discuss and compare the equilibrium degree of quality differentiation, quantity and return under the assumption of increasing and decreasing return of scale with network externality. The study shows that the product quality under decreasing returns is lower than that under increasing returns without network externality; but with network externality the quality of high_quality product under decreasing returns is higher than the one with increasing returns. The market demand under decreasing returns is lower than that under increasing returns, that is independent of the network externality.