Macroeconomic Implications of the Hartz IV Labor Market Reform

在德国实施哈茨改革十多年后，现有文献中关于量化宏观经济效应的观点仍然存在很大分歧。哈茨四世对失业率的下降有多大贡献？哈茨四世对收入不平等有多大影响？此外，关于开放经济效应的争论仍在继续：哈茨改革是否导致了经常账户盈余的大幅增加？我们的项目提案旨在从丰富的纽伦堡微观经济数据中获得指导，并将所获得的见解用于宏观经济建模。识别出的微观经济模式将使我们能够发展理论，并为我们的定量反事实练习制定纪律。在第一个项目中，我们的目标是提出一种新的方法，通过劳动力市场的宏观经济模型的透镜来评估哈茨第四改革，区分部分和均衡效果的改革。我们将使用IAB职位空缺调查来实证衡量，然后在我们的模型中针对Hartz IV的部分影响，而不是直接假设福利替代率会有一定的下降。此外，我们还将使用选择率和就业率的时间序列行为，来确定经济周期中局部效应和均衡效应的相对重要性。我们的劳动力市场的宏观经济模型将被校准到微观经济估计，并用于评估哈茨四宏观经济就业和收入的影响。此外，我们还将分析福利问题以及与其他改革（如哈茨III）的相互作用。第二个课题，从企业产出的可贸易性出发，深入探讨哈茨改革的开放经济效果。我们将根据企业产出的可交易性程度，记录在哈茨III和哈茨IV改革前后，劳动者和就业流动以及收入的变化。我们将使用行政工资和劳动力市场流动面板（AWFP），其中包含所有德国企业的流动和收入，并将其与国际风险敞口的两个来源联系起来。我们将这些实证结果与一个货币联盟模型的结果进行对比，该模型考虑了搜寻摩擦、可贸易部门和不可贸易部门。从理论角度来看，我们预计可贸易部门受到劳动力市场改革的影响更大（立即）。我们将分析这种类型的标准模型是否可以生成与具有合理参数值的数据中相似的模式。如果情况并非如此，我们将修改工资形成机制等参数和重要假设。在模型和数据足够接近的情况下，我们可以在开放经济环境中进行重要的反事实练习。如果模型和数据仍然相距甚远，该项目可能会为未来的理论研究发现一个有趣的难题。

More than a decade after the implementation of the Hartz reforms in Germany, there is still substantial disagreement about the quantitative macroeconomic effects in the existing literature. How much did Hartz IV contribute to the decline of unemployment? How much did Hartz IV affect earnings inequality? In addition, the debate on the open-economy effects is still ongoing: Did the Hartz reforms lead to a substantial increase of the current account surplus?Our project proposal aims at obtaining guidance from the rich Nuremberg based microeconomic data and to use the derived insights for macroeconomic modeling. The identified microeconomic patterns will allow us to develop theory and to discipline for our quantitative counterfactual exercises.In the first project, we aim at proposing a novel methodology to evaluate the Hartz IV reform through the lens of a macroeconomic model of the labor market that distinguishes between a partial and an equilibrium effect of the reform. Instead of directly assuming a certain reduction of the benefit replacement rate, we will use the IAB Job Vacancy Survey to empirically measure and then target the partial effect of Hartz IV in our model. Furthermore, we will use the time series behavior of the selection rate and the job-finding rate to determine the relative importance of partial and equilibrium effects over the business cycle. Our macroeconomic model of the labor market will be calibrated to the microeconomic estimates and used to evaluate the macroeconomic employment and earnings effects of Hartz IV. In addition, we will analyze welfare issues and interactions with other reform steps (such as Hartz III).In the second project, we aim at gaining deeper insights on the open-economy effects of the Hartz reforms based on the tradability of establishments’ output. We will document how worker and job flows as well as earnings changed around the time of the Hartz III and Hartz IV reforms depending on the degree of tradability of establishments’ output. We will use the Administrative Wage and Labor Market Flow Panel (AWFP), which contains flows and earnings for all German establishments, and link it with two sources on international exposure. We will contrast these empirical results with the results from a monetary union model with search frictions and a tradable and a non-tradable sector. From a theoretical perspective, we expect that the tradable sector is affected more (immediately) by labor market reforms. We will analyze whether a standard model of this type can generate similar patterns as in the data with reasonable parameter values. If this is not the case, we will modify parameters and important assumptions such as the wage formation mechanisms. In case model and data are sufficiently close, we can perform important counterfactual exercises in an open-economy setting. If model and data are nevertheless far apart, the project may discover an interesting puzzle for future theoretical research.