External refereed essays

Reducing Energy System Model Distortions from Unintended Storage Cycling through Variable Costs

Energy system models are used for policy decisions and technology designs. If not carefully used, models give implausible outputs and mislead decision-making. One implausible effect is “unintended storage cycling”, which is observable as simultaneous storage charging and discharging. Methods to remove such misleading effects exist, but are computationally inefficient and sometimes ineffective. Through ...

The Multifaceted Impact of US Trade Policy on Financial Markets

We study the multifaceted effects of trade policy shocks on financial markets using a structural vector autoregression identified via event day heteroskedasticity. We find that restrictive US trade policy shocks affect US and international stock prices heterogeneously, but generally negatively. They increase market uncertainty, lower US interest rates, and lead to an appreciation of the US dollar. ...

Monetary Policy and Mispricing in Stock Markets

We investigate the role of monetary policy in stock price misalignments and explore whether central banks can attenuate excessive mispricing as suggested by the proponents of a “leaning against the wind” monetary policy. Decomposing stock prices into expected excess dividends, an equity risk premium, and a mispricing component, we find that prices fall more strongly in response to an increase in the ...

Can a Federal Minimum Wage Alleviate Poverty and Income Inequality? Ex-post and Simulation Evidence from Germany

Minimum wages are increasingly discussed as an instrument against (in-work) poverty and income inequality in Europe. Just recently the German government opted for a substantial ad-hoc increase of the minimum-wage level to euro12 per hour mentioning poverty prevention as an explicit goal. We use the introduction of the federal minimum wage in Germany in 2015 to study its redistributive impact on disposable ...

Policy Evaluation of Waste Pricing Programs Using Heterogeneous Causal Effect Estimation

Using machine learning methods in a quasi-experimental setting, I study the heterogeneous effects of introducing waste prices - unit prices on household unsorted waste disposal - on waste demands and municipal costs. Using a unique panel of Italian municipalities with large variation in prices and observables, I show that waste demands are nonlinear. I find evidence of constant elasticities at low ...

Gender, Loneliness and Happiness during COVID-19

We analyse a measure of loneliness from a representative sample of German individuals interviewed in both 2017 and at the beginning of the COVID-19 pandemic in 2020. Both men and women felt lonelier during the COVID-19 pandemic than they did in 2017. The pandemic more than doubled the gender loneliness gap: women were lonelier than men in 2017, and the 2017-2020 rise in loneliness was far larger for ...

The Role of Pre-pandemic Depression for Changes in Depression, Anxiety, and Loneliness during the COVID-19 Pandemic: Results from a Longitudinal Probability Sample of Adults from Germany

Background: The present study aims to delineate the role of preexisting depression for changes in common mental health problems during the COVID-19 pandemic. Methods: Using mixed-effects linear regression models, we analyzed data on the course of depressive (Patient Health Questionnaire-2) and anxiety (Generalized Anxiety Disorder-2) symptoms as well as loneliness (three-item UCLA Loneliness Scale) ...

Rent Control, Market Segmentation, and Misallocation: Causal Evidence from a Large-Scale Policy Intervention

This paper studies market segmentation that arises from the introduction of rent control. When a part of the market remains unregulated, theory predicts an increase of free-market rents due to the misallocation of households to dwellings. To document this mechanism empirically, we study a large-scale policy intervention in the German housing market. We isolate the misallocation mechanism by exploiting ...

Zu wenig qualifizierte Arbeitskräfte für praktische Tätigkeiten

Energiewende steht für die Chance auf Re-Industrialisierung, nicht für De-Industrialisierung

The Expansion of Natural Gas Infrastructure Puts Energy Transitions at Risk

Whether additional natural gas infrastructure is needed or would be detrimental to achieving climate protection goals is currently highly controversial. Here we combine five perspectives to argue why expansion of the natural gas infrastructure hinders a renewable energy future and is no bridge technology. We highlight that natural gas is a fossil fuel with a significantly underestimated climate impact ...

Do Words Hurt More than Actions? The Impact of Trade Tensions on Financial Markets

We use machine learning techniques to quantify trade tensions between the United States and China. Our measure matches well-known events in the US-China trade dispute and is exogenous to the developments on global financial markets. Local projections show that rising trade tensions leave US markets largely unaffected, except for firms that are more exposed to China, while negatively impacting stock ...

How Migration Status Shapes Susceptibility of Individuals’ Loneliness to Social Isolation

Objectives: Our research provides competing hypotheses and empirical evidence how associations between objectively social isolation and subjective loneliness differ between host populations, migrants, and refugees.Methods: The analysis uses data of 25,171 participants from a random sample of the German population (SOEP v.35). We estimate regression models for the host population, migrants, and refugees ...

Substituting Clean for Dirty Energy: A Bottom-Up Analysis

We fit CES and VES production functions to data from a numerical bottom-up optimization model of electricity supply with clean and dirty inputs. This approach allows for studying high shares of clean energy not observable today and for isolating mechanisms that impact the elasticity of substitution between clean and dirty energy. Central results show that (i) dirty inputs are not essential for production. ...

Institutional Coordination Arrangements as Elements of Policy Design Spaces: Insights from Climate Policy

This study offers insights into the institutional arrangements established to coordinate policies aiming at the mitigation of and adaptation to climate change. Drawing on the literature on policy design, we highlight institutional arrangements as elements of policy design spaces and contend that they fall into four categories that either stress the political or problem orientation of this activity: ...

The Rise and Fall of Social Housing? Housing Decommodification in Long-run Comparison

The comparative study of housing decommodification lags behind classical welfare state research, while housing research itself is rich in homeownership studies but lacks comparative accounts of private and social rentals due to missing comparative data. Building on existing works and various primary sources, this study presents a new collection of up to forty-eight countries’ social housing shares ...

Parental Leave Policy and Long-run Earnings of Mothers

Paid parental leave schemes have been shown to increase women’s employment rates but to decrease their wages in case of extended leave duration. In view of these potential trade-offs, many countries are discussing the optimal design of parental leave policies. We analyze the impact of a major parental leave reform on mothers’ long-term earnings. The 2007 German parental leave reform replaced a means-tested ...

Grenzen und Fortschritte indikatorengestützter Politik am Beispiel der Corona-Pandemie: Heinz-Grohmann-Vorlesung 2020/21

Indikatoren sollen der Steuerung von (sozialen) Prozessen dienen. Sie beschreiben jedoch die Realität in der Regel nur deskriptiv und unvermeidlich mit mehr oder weniger großen und systematischen Messfehlern behaftet. Insofern ist es im Allgemeinen alles andere als einfach mit Hilfe von Indikatoren zu steuern; insbesondere dann, wenn für Problembereiche (fehlerbehaftete) Zielwerte vorgegeben werden, ...

An Alternative Bootstrap for Proxy Vector Autoregressions

We propose a new bootstrap algorithm for inference for impulse responses in structural vector autoregressive models identified with an external proxy variable. Simulations show that the new bootstrap algorithm provides confidence intervals for impulse responses which often have more precise coverage than and similar length to the competing moving-block bootstrap intervals. An empirical example shows ...

Input-Output-Beziehungen für einen Stadtstaat: die Freie und Hansastadt Hamburg als Beispiel