Equilibrium Product Lines: Competing Head-to-Head May Be Less Competitive
提出一个需求多样性模型，解释为何竞争企业可能选择相似产品线：若产品范围不同，消费者会多源采购以增加多样性，价格敏感使市场竞争激烈；若产品范围相同，消费者因多供应商成本只从一家购买，市场竞争减弱、价格更高。
The author suggests a new model of demand for variety that explains why competing firms may choose very similar product lines: if firms offer different product ranges, some consumers use multiple suppliers to increase variety and, since these consumers' purchases will be sensitive to the difference in firms' prices, the market may be fairly competitive. If, instead, firms offer identical product ranges, each consumer purchases from one firm only because of costs of using additional suppliers, so the market may be less competitive and equilibrium prices higher. This contrasts with the standard intuition that firms minimize competition by differentiating their products.