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So viel kostet FremdenfeindlichkeitReint GroppSüddeutsche Zeitung, 1. September 2026
This paper examines the macroeconomic and distributional effects of the European Union’s transition to Net Zero emissions through a gradually increasing carbon tax. I develop a New Keynesian Environmental DSGE model with two household types and distinct energy and non-energy sectors. Five alternative uses of carbon tax revenues are considered: equal transfers to households, targeted transfers to Hand-to-Mouth households, subsidies to green energy firms, and reductions in labor and capital income taxes. In the absence of technological progress, the carbon tax policy induces a persistent increase in energy prices and a reduction in GDP, investment, and consumption. Headline inflation falls below zero in the medium run, reflecting weaker aggregate demand. Distributional outcomes vary significantly depending on the implemented revenue recycling scheme: targeted transfers are the most progressive but entail larger macroeconomic costs, while subsidies and tax cuts mitigate output and investment losses but are less effective in narrowing the consumption gap. A limited foresight scenario, in which agents learn about policy targets sequentially, generates more volatile adjustment paths and temporary inflationary spikes around announcements, but long-run outcomes remain close to the baseline.
We examine how institutional saving mechanisms influence retirement saving decisions under bounded rationality and income risk. Using a life-cycle experiment with habit formation and loss aversion, we test mandatory and voluntary binding savings under deterministic and stochastic income. Voluntary commitment improves saving performance only when income is predictable; under uncertainty, it fails to improve performance. Mandatory savings do not raise total saving, as participants reduce voluntary contributions. These results emphasize the role of income smoothing in enabling behavioral interventions to improve long-term financial outcomes.
This paper examines the impact of climate risks on the debt structure of a sample of U.S. firms from 2002 through 2020. Climate risks—mainly physical, regulatory, and transition risks—are associated with a concentrated debt structure for the affected firms. However, when climate risks propagate through the channels of expected bankruptcy costs and sustainability, they are associated with a more diversified debt structure. Additionally, climate risks asymmetrically impact the relationship between access to finance and debt structure. Results from a quasi-natural experiment reaffirm the impact of climate risks on debt structure.
This study estimates the firm-level employment effects of investment grants in Germany. In addition to the average treatment effect on the treated, we examine discrimination in the funding rules as a potential source of effect heterogeneity. We combine a staggered difference-in-differences approach with a matching procedure at the cohort level. The findings reveal a positive effect of investment grants on employment development. The subsample analyses yield strong evidence for heterogeneous effects based on firm characteristics and the economic environment. They highlight the responsibility of the local funding authorities to clarify ex ante which goals of a funding programme are most important in their regions.
Climate policy design must balance emissions mitigation with concerns for fairness, particularly as climate change disproportionately affects the poorest households within and across countries. Integrated Assessment Models used for global climate policy evaluation have so far typically not considered inequality effects within countries. To fill this gap, we develop a global Integrated Assessment Model representing national economies and subnational income, mitigation cost, and climate damage distribution and assess a range of climate policy schemes with varying levels of effort sharing across countries and households. The schemes are consistent with limiting temperature increases to 2 °C and account for the possibility to use carbon tax revenues to address distributional effects within and between countries. We find that carbon taxation with redistribution improves global welfare and reduces inequality, with the most substantial gains achieved under uniform taxation paired with global per capita transfers. A Loss and Damage mechanism offers significant welfare improvements in vulnerable countries while requiring only a modest share of global carbon revenues in the medium term. The poorest households within all countries may benefit from the transfer scheme, in particular when some redistribution is made at the country level. Our findings underscore the potential for climate policy to advance both environmental and social goals, provided revenue recycling mechanisms are effectively implemented. In particular, they demonstrate the feasibility of a welfare improving global climate policy involving limited international redistribution.
Deutschland befand sich in den vergangenen zwei Jahren in der Rezession. Die jüngst stark revidierten Volkswirtschaftlichen Gesamtrechnungen zeigen, dass die Krise deutlich ausgeprägter war als bislang ausgewiesen. Mit einer Stagnation in der ersten Hälfte dieses Jahres dürfte die deutsche Wirtschaft die konjunkturelle Talsohle erreicht haben. Eine breit angelegte Erholung ist allerdings nicht zu erwarten, denn grundlegende strukturelle Schwächen dauern an.
Die Konjunktur dürfte in den kommenden zwei Jahren durch die Finanzpolitik expansive Impulse erfahren. Während die Dienstleistungsbereiche, insbesondere im öffentlichen Sektor, weiterhin kräftig zulegen, wird die Erholung im Produzierenden Gewerbe wohl nur verhalten ausfallen. Vor allem dürfte sich die Auslandsnachfrage nach deutschen Waren nicht zuletzt infolge der US-Zollpolitik weiterhin nur schleppend entwickeln. Die geplanten öffentlichen Ausgaben für Verteidigung und Infrastruktur können dies nur begrenzt abfedern, denn ein erheblicher Teil der Mittel fließt in gesamtwirtschaftlich kleine Bereiche, in denen die bestehenden Kapazitäten bereits gut ausgelastet sind. Insgesamt dürfte es in den kommenden beiden Jahren zu Kapazitätsausweitungen und entsprechenden privaten Investitionen kommen.
Das Bruttoinlandsprodukt dürfte in diesem Jahr mit einem Anstieg um 0,2 % kaum mehr als stagnieren. Im weiteren Prognosezeitraum dürfte eine expansive Finanzpolitik die Konjunktur anschieben. Im kommenden Jahr steigt das Bruttoinlandsprodukt um 1,3 % und im Jahr 2027 um 1,4 %. Damit lassen die Institute ihre Prognose für das laufende und kommende Jahr im Vergleich zum Frühjahr in etwa unverändert.
Vietnam, a lower-middle-income economy, faces severe climate risks from heat waves, sea-level rise, and tropical cyclones, which are expected to intensify under ongoing global warming. Using a dynamic general equilibrium model, we analyze economic transition dynamics from 2015 to 2100, incorporating heat-induced labor productivity losses, agricultural land loss, and cyclone-related property damage. We compare a Paris-compatible scenario limiting warming to below 2 °C with a high-emission scenario reaching 4–5 °C. While output and investment impacts remain highly uncertain and statistically indistinguishable across scenarios until 2100, consumption losses are significantly larger under high emissions, mainly driven by heat-related productivity declines, with cyclones contributing most to uncertainty. These findings underscore the importance of considering multiple impact channels beyond output damages in climate-development research.
Predicting IPO first-day returns is inherently challenging due to the wide range of contributing factors, each with distinct statistical properties. We assess the performance of several machine learning (ML) techniques and identify XGBoost as the most statistically effective model for forecasting first-day returns. Using a comprehensive set of 863 pre-IPO variables, our high-performing predictive model accurately estimates both the direction and magnitude of IPO first-day returns. The most influential predictors include underwriter agency measures, price revision, and the free-float fraction. Using a rolling-window predictive approach, the model demonstrates substantial practical value, generating approximately $300 billion in gains from IPOs with positive first-day returns and avoiding more than $22 billion in losses from those with negative returns over the 2000–2016 period.
This paper introduces a novel measure to quantify firms’ sensitivity to shifts in bilateral trade flows between the United States and its trading partners. We exploit the 2016 U.S. presidential election as an exogenous shock to trade policy expectations and assess the stock market reactions of firms across 52 countries. Our findings indicate that firms with higher trade policy sensitivity experienced significantly more negative stock returns surrounding the election. These results are robust to variations in event windows, return model specifications, and alternative estimations of trade policy sensitivity.
We examine the survival prospects, employment profiles, and patient outcomes at private equity (PE)-acquired hospitals. Target hospitals maintain their survival rates while significantly reducing employment and wage expenditures. The number of core medical workers drops temporarily, but returns to its pre-acquisition level in the long run. However, administrative job and wage cuts persist over the long term, particularly at previously nonprofit hospitals. Using proprietary insurance claims data, we find no significant changes in patient demographics or inpatient prices at PE-acquired hospitals. While patient satisfaction declines, there is no evidence of increased patient mortality or readmission rates at PE-acquired hospitals.
