We consider demand function competition with a finite number of agents and private information. We show that any degree of market power can arise in the unique equilibrium under an information structure that is arbitrarily close to complete information. Regardless of the number of agents and the correlation of payoff shocks, market power may be arbitrarily close to zero (the competitive outcome) or arbitrarily large (so there is no trade). By contrast, price volatility is always lower than the variance of the aggregate shock across all information structures. Alternative trading mechanisms lead to very distinct bounds as a comparison with Cournot competition establishes.

中文翻译：

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信息，市场力量和价格波动

我们考虑具有有限数量的代理和私人信息的需求函数竞争。我们表明，在任意接近完整信息的信息结构下，独特的均衡中可以产生任何程度的市场支配力。无论代理人的数量和回报冲击的相关性如何，市场支配力可能任意接近零（竞争结果）或任意大（因此没有交易）。相比之下，价格波动率始终低于所有信息结构中总冲击的方差。与古诺竞争的建立相比，替代性交易机制导致了截然不同的界限。