Synthesizing Cash for Clunkers: Stabilizing the Car Market, Hurting the Environment

We examine the impact of European car scrappage programs on new vehicle registrations and respective CO2 emissions. To construct proper counterfactuals, we develop MSCM-T, the multivariate synthetic control method using time series of economic predictors. Applying MSCM-T to a rich data set covering two outcomes of interest, ten economic predictors, and 23 countries, we first analyze Germany which implemented the largest program. We find that the German subsidy had an immensely positive effect of 1.3 million program-induced new car registrations. Disentangling this effect reveals that almost one million purchases were not pulled forward from future periods, worth more than three times the program's 5 billion budget. However, stabilizing the car market came at the cost of 2.4 million tons of additional CO2 emissions. For other European countries with comparable car retirement schemes, we show further positive results regarding vehicle registrations. Finally, we demonstrate that all non-scrapping countries could have considerably backed their vehicle markets by adopting scrappage subsidies

Students' Wage Expectations in Germany - New Evidence considering Tax Adjusted Estimates

This paper uses a rich dataset derived from a three-year survey to gain insights about the informational background of University applicants. We analyze the extent to which students expectations of their starting and future salary depend on different characteristics. More precisely, the paper investigates whether students with different backgrounds tend towards making larger or smaller errors when estimating salaries. The results point out that students salary estimates are heterogeneous and that this variation is correlated with individual traits and chosen subjects. Overall, students substantially underestimate actual starting salaries by about 20 percent. However, a prime finding of this paper is that estimation errors are highly attributable to students misconception of the German progressive income tax system. Correcting for the erroneous gross-net conversion, we find applicants to have a quite correct idea about what salaries to expect in the future. Overall, applicants adjusted expectations are in line with labor market outcomes. However, expectations remain strongly correlated with personal traits

CO2 adsorption performance of pyrolized and activated waste streams

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Goodbye smokers' corner: Health effects of school smoking bans

We estimate the causal impact of school smoking bans in Germany on the propensity and intensity of smoking. Using representative longitudinal data, we use variation in state, year, age cohort, school track, and survey time for implementation of such smoking bans to identify the effects of interest. The estimates from our multipledifferences approach show that six to ten years after intervention, propensity towards smoking is reduced by 7-16 percent, while the number of smoked cigarettes per day decreases by 8-13 percent. Our results still hold if we account for the clustered data structure by evaluating the effects with randomization inference.Wir untersuchen die kausalen Auswirkungen des Rauchverbots an Schulen in Deutschland auf die Wahrscheinlichkeit zu rauchen und die Anzahl gerauchter Zigaretten pro Tag. Um diese Effekte zu messen, verwenden wir einen repräsentativen Paneldatensatz und nutzen Variationen zwischen Bundesländern, Jahren, Alterskohorten, Schulformen und Interviewzeitpunkten in Bezug auf das Inkrafttreten der Intervention. Die Schätzungen unseres multiplen Differenzenansatzes zeigen, dass sich sechs bis zehn Jahre nach Einführung der Verbote an Schulen die Wahrscheinlichkeit zu rauchen um 7-17 Prozent reduziert, während die Anzahl an gerauchten Zigaretten pro Tag um 8-13 Prozent sinkt. Unsere Ergebnisse bleiben auch dann robust, wenn wir der Clusterstruktur der Daten Rechnung tragen und die Effekte mit Randomisierungsinferenz evaluieren

Illuminating the World Cup effect : night lights evidence from South Africa

This paper evaluates the economic impact of the $14 billion preparatory investments for the 2010 FIFA World Cup in South Africa. We use satellite data on night light luminosity at municipality and electoral district level as a proxy for economic development, applying synthetic control methods for estimation. For the average World Cup municipality, we find significantly positive, short-run effects before the tournament, corresponding to a reduction of unemployment by 1.3 percentage points. At the electoral district level, we reveal distinct effect heterogeneity, where especially investments in transport infrastructure are shown to have long-lasting, positive effects, particularly in more rural areas

Cold flow modelling of dual fluidised bed pyrolysi

High temperature pyrolysis at about 600-700°C of carbon containing waste materials (plastic waste, shredded old tires, biogenic residues, etc.) is an attractive technology for substitution of fossil fuels in industrial processes. A dual fluidized bed system is investigated in a scaled cold flow model. This model consists of a riser as combustion section and a bubbling fluidized bed as pyrolysis section. The pyrolysis section is aimed to convert the solid feed material into pyrolysis oil as well as permanent gas components. This gas stream can be directly used e.g. in rotary kilns at temperatures of 400-600°C with high tar content and therefore high heating value. The char is transported with the bed material to the riser to provide the energy for the pyrolysis, transported via the hot bed material. Moreover, the pyrolysing section will be used to separate unconvertable materials such as metal pieces, stones, etc. from the process. For certain feed materials the pyrolysing section could be built as circulating fluidized bed to perform a classification of the feed material. Thus different residence time in the pyrolyser can be achieved, depending on the fuel particle size and fluidization. The results are displayed inside a regime map of gas-solid fluidized beds. Bed material residence times as well as residence times of model particles of the feedstock are given. The investigations lead to a design of a system to be applicable for various feedstock materials as input for industrial processes

Cold flow modelling of dual fluidised bed pyrolysis

High temperature pyrolysis at about 600-700°C of carbon containing waste materials (plastic waste, shredded old tires, biogenic residues, etc.) is an attractive technology for substitution of fossil fuels in industrial processes. A dual fluidized bed system is investigated in a scaled cold flow model. This model consists of a riser as combustion section and a bubbling fluidized bed as pyrolysis section. The pyrolysis section is aimed to convert the solid feed material into pyrolysis oil as well as permanent gas components. This gas stream can be directly used e.g. in rotary kilns at temperatures of 400-600°C with high tar content and therefore high heating value. The char is transported with the bed material to the riser to provide the energy for the pyrolysis, transported via the hot bed material. Moreover, the pyrolysing section will be used to separate unconvertable materials such as metal pieces, stones, etc. from the process. For certain feed materials the pyrolysing section could be built as circulating fluidized bed to perform a classification of the feed material. Thus different residence time in the pyrolyser can be achieved, depending on the fuel particle size and fluidization. The results are displayed inside a regime map of gas-solid fluidized beds. Bed material residence times as well as residence times of model particles of the feedstock are given. The investigations lead to a design of a system to be applicable for various feedstock materials as input for industrial processes

O₂-sensitive microcavity arrays: A new platform for oxygen measurements in 3D cell cultures

Oxygen concentration plays a crucial role in (3D) cell culture. However, the oxygen content in vitro is usually not comparable to the in vivo situation, which is partly due to the fact that most experiments are performed under ambient atmosphere supplemented with 5% CO2, which can lead to hyperoxia. Cultivation under physiological conditions is necessary, but also fails to have suitable measurement methods, especially in 3D cell culture. Current oxygen measurement methods rely on global oxygen measurements (dish or well) and can only be performed in 2D cultures. In this paper, we describe a system that allows the determination of oxygen in 3D cell culture, especially in the microenvironment of single spheroids/organoids. For this purpose, microthermoforming was used to generate microcavity arrays from oxygensensitive polymer films. In these oxygen-sensitive microcavity arrays (sensor arrays), spheroids cannot only be generated but also cultivated further. In initial experiments we could show that the system is able to perform mitochondrial stress tests in spheroid cultures to characterize mitochondrial respiration in 3D. Thus, with the help of sensor arrays, it is possible to determine oxygen label-free and in real-time in the immediate microenvironment of spheroid cultures for the first time

Does Unfairness Hurt Women? The Effects of Losing Unfair Competitions

How do men and women differ in their persistence after experiencing failure in a competitive environment? We tackle this question by combining a large online experiment (N=2,086) with machine learning. We find that when losing is unequivocally due to merit, both men and women exhibit a significant decrease in subsequent tournament entry. However, when the prior tournament is unfair, i.e., a loss is no longer necessarily based on merit, women are more discouraged than men. These results suggest that transparent meritocratic criteria may play a key role in preventing women from falling behind after experiencing a loss

Perceived wages and the gender gap in STEM fields

We estimate gender differences in elicited wage expectations among German Uni- versity students applying for STEM and non-STEM fields. Descriptively, women expect to earn less than men and also have lower expectations about wages of average graduates across different fields. Using a two-step estimation procedure accounting for self-selection, we find that the gender gap in own expected wages can be explained to the extent of 54-69% by wage expectations for average graduates across different fields. However, gender differences in the wage expectations for average graduates across different fields do not contribute to explaining the gender gap in the choice of STEM majors