This paper is concerned with an old question: Will oligopolistic firms have incentives to merge to monopoly and will the monopoly, if the firms indeed merge, be stable? To answer this question, I motivate and introduce a new core concept for a general partition function game and prove stability of the merger-to-monopoly by applying the new core concept, labelled the strong-core, to Cournot oligopoly modelled as a partition function game. The paper shows that the Cournot oligopoly with any finite number of homogeneous firms without capacity constraints admits a non-empty strong-core and so does the Cournot oligopoly of not necessarily homogeneous firms with capacity constraints that are equal to their “historical” outputs. These results imply that oligopolistic firms will have incentives to merge to monopoly both in the long- and short-run and if the firms indeed merge to monopoly, the merger-to-monopoly will be stable.

中文翻译：

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兼并垄断的稳定性和分割函数博弈的核心概念

本文关注的是一个古老的问题：寡头垄断企业是否有合并到垄断的动机，如果企业确实合并，垄断是否会稳定？为了回答这个问题，我为一般的分区函数博弈激发并引入了一个新的核心概念，并通过将标记为强核的新核心概念应用到古诺寡头模型作为分区函数来证明合并到垄断的稳定性游戏。该论文表明，任何有限数量的没有能力约束的同质公司的古诺寡头垄断承认一个非空的强核，并且不一定具有等于其“历史”产出的能力约束的同质公司的古诺寡头垄断也是如此。