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Wie der Iran-Krieg einen Aufschwung bremsen könnteOliver HoltemöllerTagesschau.de, 12. März 2026
The dispersion of individual returns to experience, often referred to as heterogeneity of income profiles (HIP), is a key parameter in empirical human capital models, in studies of life‐cycle income inequality, and in heterogeneous agent models of life‐cycle labor market dynamics. It is commonly estimated from age variation in the covariance structure of earnings. In this study, I show that this approach is invalid and tends to deliver estimates of HIP that are biased upward. The reason is that any age variation in covariance structures can be rationalized by age‐dependent heteroscedasticity in the distribution of earnings shocks. Once one models such age effects flexibly the remaining identifying variation for HIP is the shape of the tails of lag profiles. Credible estimation of HIP thus imposes strong demands on the data since one requires many earnings observations per individual and a low rate of sample attrition. To investigate empirically whether the bias in estimates of HIP from omitting age effects is quantitatively important, I thus rely on administrative data from Germany on quarterly earnings that follow workers from labor market entry until 27 years into their career. To strengthen external validity, I focus my analysis on an education group that displays a covariance structure with qualitatively similar properties like its North American counterpart. I find that a HIP model with age effects in transitory, persistent and permanent shocks fits the covariance structure almost perfectly and delivers small and insignificant estimates for the HIP component. In sharp contrast, once I estimate a standard HIP model without age‐effects the estimated slope heterogeneity increases by a factor of thirteen and becomes highly significant, with a dramatic deterioration of model fit. I reach the same conclusions from estimating the two models on a different covariance structure and from conducting a Monte Carlo analysis, suggesting that my quantitative results are not an artifact of one particular sample.
In this paper, we study the relationship between financial literacy and self‐employment. We use established financial literacy questions to measure literacy levels. The analysis shows a highly significant and positive correlation between the index and self‐employment. We address the direction of causality by applying instrumental variable techniques based on information about maternal education. We also exploit information on financial support and family background to account for concerns about the exclusion restriction. The results provide support for a positive effect of financial literacy on the probability of being self‐employed. As financial literacy is acquirable, the findings suggest that entrepreneurial activities might be increased by enhancing financial literacy.
The existing empirical literature on the impact of vertical grants on local public-sector efficiency yields mixed results. Given the fact that vertical financial equalization systems often reduce differences in fiscal capacity, we argue that empirical studies based on cross-sectional data may yield a positive relationship between grants and efficiency of public service production even when the underlying causal effect is not. We provide a simple illustrative theoretical model to show the logic of our argument and illustrate its relevance by an empirical case study for the German state of Saxony-Anhalt. We show that our main argument of an inference-disturbing effect applies to those existing studies that are more optimistic about the impact of vertical grants. Finally, we argue that it may disturb the inference drawn from studies in a number of other countries where vertical grants—intended or not—concentrate in fiscally weak municipalities.
Student achievement varies widely across developed countries, but the source of these differences is not well understood. One obvious candidate, and a major focus of research and policy discussions both in the United States and abroad, is teacher quality.
Trade unions and employers’ associations, collective bargaining, and employee representation at the workplace are the cornerstones of industrial relations systems in many developed countries. Germany stands out as a country with powerful works councils and a high coverage rate of collective bargaining agreements, supported by encompassing interest groups of employees and employers and by the state. The German case and the perceived stability of its industrial relations regime have attracted considerable attention among researchers and politicians, which also has to do with the country’s high productivity, comparably few strikes, and relatively minor employment problems. However, in recent years industrial relations in many countries including Germany have come under pressure and the fact that there is no obvious and clearly superior alternative to the current regime of industrial and labour relations may not be sufficient to guarantee the survival of the present system.
Interactive regional learning involving various actors is considered a precondition for successful innovations and, hence, for regional development. Diasporas as non-native ethnic groups are regarded as beneficial since they enrich the creative class by broadening the cultural base and introducing new routines. Using data on research and development (R&D) collaboration projects, the analysis provides tentative evidence that the size of diasporas positively affects the region’s share of outward R&D linkages enabling the exchange of knowledge. The empirical analysis further confirms that these interactions mainly occur between regions hosting the same diasporas, pointing to a positive effect of ethnic proximity rather than ethnic diversity.
In this article, we use cross-state panel and cross-U.S. commuting-zone data to look at the relationship between innovation, top income inequality and social mobility. We find positive correlations between measures of innovation and top income inequality. We also show that the correlations between innovation and broad measures of inequality are not significant. Next, using instrumental variable analysis, we argue that these correlations at least partly reflect a causality from innovation to top income shares. Finally, we show that innovation, particularly by new entrants, is positively associated with social mobility, but less so in local areas with more intense lobbying activities.
In this paper, we investigate the impact of regional and technological innovation systems on innovation cooperation. We develop an indicator applicable to regions, which demonstrates the relative regional impact on innovation cooperation. Applying this method to German patent data, we find that regional differences in the degree of innovation cooperation do not only depend on the technology structure of a region but also on specific regional effects. High-tech oriented regions, whether east or west, are not automatically highly cooperative regions. East German regions have experienced a dynamic development of innovation cooperation since re-unification in 1990. Their cooperation intensity remains higher than in West German regions.
We use Hurricane Katrina’s damage to the Mississippi coast in 2005 as a natural experiment to study business survival in the aftermath of a capital-destruction shock. We find very low survival rates for businesses that incurred physical damage, particularly for small firms and less-productive establishments. Conditional on survival, larger and more-productive businesses that rebuilt their operations hired more workers than their smaller and less-productive counterparts. Auxiliary evidence from the Survey of Business Owners suggests that the differential size effect is tied to the presence of financial constraints, pointing to a socially inefficient level of exits and to distortions of allocative efficiency in response to this negative shock. Over time, the size advantage disappeared and market mechanisms seem to prevail.
We build a model of firm-level innovation, productivity growth, and reallocation featuring endogenous entry and exit. A new and central economic force is the selection between high- and low-type firms, which differ in terms of their innovative capacity. We estimate the parameters of the model using US Census microdata on firm-level output, R&D, and patenting. The model provides a good fit to the dynamics of firm entry and exit, output, and R&D. Taxing the continued operation of incumbents can lead to sizable gains (of the order of 1.4 percent improvement in welfare) by encouraging exit of less productive firms and freeing up skilled labor to be used for R&D by high-type incumbents. Subsidies to the R&D of incumbents do not achieve this objective because they encourage the survival and expansion of low-type firms.
