Understanding the minimum wage effects on imperfect product and labour markets

尽管如今大多数国家都有最低工资，但其影响在科学家和政策制定者中仍是一个有争议的问题。特别是，关于公司的竞争环境如何影响他们对最低工资引起的劳动力成本冲击的调整，人们知之甚少。在此背景下，本项目首次详细研究了企业的产品和劳动力市场力量如何影响其对最低工资的反应。为了在公司层面衡量产品和劳动力市场力量，该项目依赖于最近的一种方法，该方法允许从生产函数估计中推断出这两种类型的市场力量。具体地说，这种方法提供了直接的企业层面的衡量标准，包括价格高于边际成本的加价、企业在低于竞争性工资的情况下的垄断能力，以及工人在高于竞争性工资的情况下的垄断能力。我们使用来自德国官方公司数据的高质量管理公司面板数据实施了这一方法，然后在三篇论文中研究了产品和劳动力市场的缺陷如何影响公司对最低工资的反应。在识别方面，我们依靠企业层面的三重差异方法来调查2015年德国引入最低工资的影响，这取决于引入最低工资之前公司的产品和劳动力市场力量。该项目的三篇论文不仅重新审视了最低工资的就业效应，调查了产品和劳动力市场缺陷如何影响企业的就业反应，而且首次提供了关于这两种类型的市场缺陷与进一步反应之间相互作用的全面证据。除了就业外，我们还考虑公司在产量、产品价格、生产率和劳动力替代方面的调整。出于几个原因，从科学和政策的角度来看，理解这种相互作用都是至关重要的。教科书上的劳动力市场垄断模型预测，最低工资不仅可以提高工人的工资，还可以增加就业、产出和效率。因此，研究劳动力市场缺陷的普遍性及其如何影响最低工资效应，从而提供了解释最低工资对就业的适度影响的机会，并有望深入了解最低工资可能对福利产生的影响。商品市场垄断的教科书模型预测，企业可能会通过提高消费者的产品价格来转嫁他们增加的劳动力成本，然后消费者支付最低工资。因此，研究企业对最低工资的反应如何随着其产品市场力量的变化而变化，对于理解最低工资如何影响工人福利非常重要，并可能揭示竞争和劳动力市场政策之间的关键相互作用。因此，我们预计我们的发现将引起科学家和政策制定者的极大兴趣。

Whereas minimum wages are present in most countries nowadays, their effects remain a controversial issue among scientists and policymakers. In particular, little is known on how the competitive environment of firms affects their adjustments to the labour cost shock induced by a minimum wage. Against this background, this project is first to study in detail how firms’ product and labour market power shape their responses to the minimum wage. To measure product and labour market power at the firm level, the project relies on a recent methodology that allows to infer both types of market power from production function estimates. Specifically, this methodology provides direct firm-level measures of the mark-up of prices over marginal costs, of firms’ monopsony power in case of below competitive wages, and of workers’ monopoly power in case of above competitive wages. We implement this methodology using high-quality administrative firm panel data from the Official Firm Data for Germany (Amtliche Firmendaten für Deutschland, AFiD) and then study in three papers how product and labour market imperfections shape firms’ responses to the minimum wage. In terms of identification, we rely on a firm-level triple differences approach to investigate the effects of the introduction of the minimum wage in Germany in 2015 depending on firms’ product and labour market power prior to the minimum wage introduction. The three papers of this project not only revisit the employment effect of the minimum wage and investigate how product and labour market imperfections shape firms’ employment response, but also provide first comprehensive evidence on the interaction between both types of market imperfections and further responses. Apart from employment, we consider firms’ adjustments in terms of output, product prices, productivity, and labour substitution. Understanding such interactions is vital both from a scientific and policy point of view for several reasons. Textbook models of labour market monopsony predict that the minimum wage may not only improve workers’ wages but also increase employment, output, and efficiency. Studying the prevalence of labour market imperfections and how they shape the minimum wage effect thus offers the opportunity of explaining the modest employment effects of minimum wages found empirically and promises insights into the likely welfare implications of the minimum wage. Textbook models of goods market monopoly predict that firms may pass through their increased labour costs by raising product prices for consumers who then pay for the minimum wage. Studying how firms’ responses to the minimum wage vary with their product market power is thus important for understanding how the minimum wage affects worker welfare and is likely to reveal crucial interactions between competition and labour market policy. Therefore, we expect our findings to be of significant interest to scientists and policymakers alike.