The Neo-Luddite's Lament: Excessive Upgrades in the Software Industry
分析垄断软件供应商为何推出过多升级，原因包括承诺问题和消费者异质性，导致社会效率损失。
We examine two reasons why a monopoly supplier of software may introduce more upgrades than is socially optimal when the upgrade is backward but not forward compatible, so users who upgrade reduce others' network benefits. One explanation involves a commitment problem: profits and social welfare may suffer because ex post the monopolist will want to sell the upgraded product to new consumers. The second involves consumer heterogeneity. Here oversupply arises from the difference between the externality that upgrades impose on the marginal and average consumer, and from the effect of upgrades on sales of the base good.