Product Diversity in Asymmetric Oligopoly: Is the Quality of Consumer Goods too Low?
研究了寡头市场中水平差异化和质量差异的模型，发现高质量商品定价过高且产量不足，而低质量商品可能在社会净贡献为负时仍有利可图，导致过度进入。
We analyse an oligopoly model incorporating horizontal differentiation and quality differences. High quality goods are overpriced and underproduced. When the market is fairly well covered, low quality products may be profitable when their net social contribution is negative, implying excessive entry. In a relatively uncovered market, even low quality goods are underproduced and there may be underentry. When fixed costs are independent of quality, the market tends to select the right firms. Otherwise, the market may produce low quality products when it should produce high quality ones. The model is calibrated using market data for yoghurt.