We examine the welfare effects of entry in the presence of network externalities. We show that if network goods are fully incompatible, entry is socially insufficient as long as the entry cost is high, the goods are sufficiently differentiated, and the degree of network externality is low. Further, we show that as the degree of compatibility between the network goods increases, insufficient entry becomes more likely. Our findings provide policy guidelines for anticompetitive and procompetitive entry regulations.

中文翻译：

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进入的社会效率：网络外部性的影响

我们研究了在存在网络外部性的情况下进入的福利效应。我们表明，如果网络商品完全不相容，只要进入成本高、商品充分分化、网络外部性程度低，则进入在社会上是不足的。此外，我们表明，随着网络商品之间的兼容性程度增加，进入不足的可能性变得更大。我们的研究结果为反竞争和促进竞争的进入法规提供了政策指导。