Natural Selection in Markets

市场自然选择

• 批准号: 9808690
• 负责人: Lawrence Blume
• 金额: --
• 依托单位: Cornell University
• 依托单位国家: 美国
• 项目类别: Continuing grant
• 财政年份: 1998
• 资助国家: 美国
• 起止时间: 1998-07-01 至 2002-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9808690&HistoricalAwards=false
• 关键词: Natural; Selection; Markets

The most common theoretical defense of the hypothesis that firms maximize profits is that otherwise they will be driven out of the market. The idea is that only those firms which for whatever reason succeed in maximizing profits will able to attract or accumulate enough capital to survive and grow. Although this intuition has been around for a long time (see Alchian (1950), Friedman (1953) and Winter (1964, 1971)) it has not been investigated in a general equilibrium setting. The argument also has its critics. In particular, Koopmans (1957) argued that referencing an external dynamic process to support the validity of a key behavioral assumption is not really a satisfactory way to proceed. In the work leading up to this proposal we have examined this hypothesis in a simple general equilibrium model in which firms fund current operations from retained earnings, without access to external financial capital markets. This dynamic, much like that discussed by Winter, drives the scale of firm operation. We found that among all firms having access to the same technology only those that come closest to maximizing profits survive. But Koopmans is nonetheless right. The tendency to select for profit maximizers does not generate a corresponding selection for aggregate producer efficiency. In the absence of markets for financial capital, the retained earnings dynamic is not able to reallocate funds across firms so as to achieve producer efficient outcomes. The addition of capital markets `solves` the problem in that if all investors have rational expectations, and markets are dynamically complete, then the equilibrium is efficient. But this begs the question. More interesting is what happens if not all investors have rational expectations. In this case the result can be even worse than without financial capital markets. Our research plan can be characterized as taking Koopmans' concern seriously. We are interested in what does happen when firms do not necessarily maximize profits, and investors are not necessarily rational, but the forces of economic natural selection are at work. What characteristics does the sequence of equilibria display? What are the asymptotic properties? Are there any optimality properties for either the sequence of equilibria or for the limit equilibria? We know that profit maximizers are selected for in some settings and not in others, but can the fit decision rules be characterized generally? These questions are particularly interesting when profits are random and firms cannot be valued through arbitrage. In this case it is not clear what objective to attribute to a firm. Our preliminary investigation suggest that there is no tendency to select for expected profit maximization even when that is what capitalists want. Instead we conjecture that there will be selection for firms that act so as to maximize the expected growth rate of their retained earnings. This is not consistent with expected profit maximization, but it is consistent with popular commentary about the objectives of large corporations.

对于公司利润最大化这一假设，最常见的理论辩护是，否则它们将被赶出市场。其理念是，只有那些无论出于何种原因成功实现利润最大化的公司，才能吸引或积累足够的资本来生存和发展。尽管这种直觉已经存在很长一段时间了(参见Alchian(1950)，Friedman(1953)和温特(1964,1971))，但还没有人在一般均衡环境中对其进行研究。这一论点也有批评者。特别是，库普曼(1957)认为，引用外部动态过程来支持关键行为假设的有效性并不是一种真正令人满意的继续下去的方式。在这项提议之前的工作中，我们在一个简单的一般均衡模型中检验了这一假设，在该模型中，公司从留存收益中为当前的运营提供资金，而不是进入外部金融资本市场。这种动态，就像温特所讨论的那样，推动了公司运营的规模。我们发现，在所有能够获得相同技术的公司中，只有那些最接近利润最大化的公司才能生存下来。但库普曼斯仍然是正确的。选择利润最大化者的倾向并不会产生对综合生产者效率的相应选择。在缺乏金融资本市场的情况下，留存收益动态不能在公司之间重新分配资金，从而实现生产者的有效结果。资本市场的加入解决了这样一个问题：如果所有投资者都有理性预期，并且市场是动态完备的，那么均衡是有效的。但这回避了一个问题。更有趣的是，如果不是所有投资者都有理性预期，会发生什么。在这种情况下，结果可能比没有金融资本市场还要糟糕。我们的研究计划可以说是认真对待库普曼的关切。我们感兴趣的是，当公司不一定实现利润最大化，投资者不一定是理性的，但经济自然选择的力量正在发挥作用时，会发生什么。均衡的顺序表现出什么特征？渐近性质是什么？平衡点序列或极限平衡点有什么最优性吗？我们知道，利润最大化者在某些情况下是被选择的，而在另一些情况下则不是，但合适的决策规则能否被普遍描述？当利润是随机的，而且无法通过套利对公司进行估值时，这些问题尤其有趣。在这种情况下，不清楚应该将什么目标归因于一家公司。我们的初步调查表明，没有选择预期利润最大化的倾向，即使这是资本家想要的。相反，我们猜测，将有选择的公司采取行动，以最大化其留存收益的预期增长率。这与预期的利润最大化不一致，但与流行的关于大公司目标的评论是一致的。