Hertie School Research Repository
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Women’s employment, income and divorce in West Germany: a causal approach
No full textIn this paper, I assess the employment and income effect of divorce for women in West Germany between 2000 and 2005. With newly available administrative data that allows me to adopt a causal approach, I find strong negative employment effects with respect to marginal employment and strong positive effects with respect to regular employment. However, in sum, the overall employment rate (marginal and regular employment combined) is not affected. Furthermore, the lower the labor market attachment before separation is, the more pronounced employment effects are. In addition, I also estimate the impact of divorce on daily gross incomes. I find no convincing evidence for an income effect. I conclude that a divorce might have a pure labor supply effect only
“Hashjacking” the Debate: Polarisation Strategies of Germany’s Political Far-Right on Twitter
No full textTwitter is a digital forum for political discourse. The emergence of phenomena like fake news and hate speech has shown that political discourse on micro-blogging can become strongly polarised by algorithmic enforcement of selective perception. Recent findings suggest that some political actors might employ strategies to actively facilitate polarisation on Twitter. With a network approach, we examine the case of the German far-right party Alternative für Deutschland (AfD) and their potential use of a “hashjacking” strategy (The use of someone else’s hashtag in order to promote one’s own social media agenda.). Our findings suggest that right-wing politicians (and their supporters/retweeters) actively and effectively polarise the discourse not just by using their own party hashtags, but also by “hashjacking” the political party hashtags of other established parties. The results underline the necessity to understand the success of right-wing parties, online and in elections, not entirely as a result of external effects (e.g. migration), but as a direct consequence of their digital political communication strategy
Joint reconstruction and classification of tumor cells and cell interactions in melanoma tissue sections with synthesized training data
No full textPurpose
Cancers are almost always diagnosed by morphologic features in tissue sections. In this context, machine learning tools provide new opportunities to describe tumor immune cell interactions within the tumor microenvironment and thus provide phenotypic information that might be predictive for the response to immunotherapy.
Methods
We develop a machine learning approach using variational networks for joint image denoising and classification of tissue sections for melanoma, which is an established model tumor for immuno-oncology research. The manual annotation of real training data would require substantial user interaction of experienced pathologists for each single training image, and the training of larger networks would rely on a very large number of such data sets with ground truth annotation. To overcome this bottleneck, we synthesize training data together with a proper tissue structure classification. To this end, a stochastic data generation process is used to mimic cell morphology, cell distribution and tissue architecture in the tumor microenvironment. Particular components of this tool are random placement and rotation of a large number of patches for presegmented cell nuclei, a stochastic fast marching approach to mimic the geometry of cells and texture generation based on a color covariance analysis of real data. Here, the generated training data reflect a large range of interaction patterns.
Results
In several applications to histological tissue sections, we analyze the efficiency and accuracy of the proposed approach. As a result, depending on the scenario considered, almost all cells and nuclei which ought to be detected are actually marked as classified and hardly any misclassifications occur.
Conclusions
The proposed method allows for a computer-aided screening of histological tissue sections utilizing variational networks with a particular emphasis on tumor immune cell interactions and on the robust cell nuclei classification
Systematic edge uncertainty in attributed social networks and its effects on rankings of minority nodes
No full textNetwork analysis provides powerful tools to learn about a variety of social systems. However, most analyses implicitly assume that the considered data is error-free and reliable. Especially if the network consists of multiple groups, this assumption conflicts with the range of systematic reporting biases, measurement errors and other inaccuracies that are well documented in our community. In this paper, we model how such systematic uncertainty on edges of an attributed network can impact network analysis, in particular the ranking of nodes. We discuss how erroneous edge observations can be driven by external node attributes and the relative edge positions in the network, thereby opening a path towards a systematic study of the effects of edge-uncertainty for various network analysis tasks. To show how conclusions drawn from network analyses can get distorted due to such inaccuracies, we focus on the effects of edge-uncertainty on minority group representations in degree-based rankings. For that purpose, we analyze synthetic and real networks with varying homophily and group sizes. We find that introducing edge uncertainty can significantly alter the relative density of networks and result both in a strongly increased or decreased ranking of the minority, depending on the type of edge error and homophily. Our model enables researchers to include systematic edge-uncertainty in their analyses and thereby better account for the role of minorities in social networks
Geflüchtete, Familien und ihre Kinder: warum der Blick auf die Familien und die Kindertagesbetreuung entscheidend ist
No full textSeit 2015 viele Menschen mit Fluchthintergrund nach Deutschland gezogen sind, stand häufig deren Arbeitsmarktintegration im Zentrum des gesellschaftlichen, politischen und wissenschaftlichen Interesses. Lebenslagen und Lebensformen der gefluchteten Familien wurden hingegen viel weniger thematisiert. Dieser Beitrag präsentiert familiendemografische Daten für Gefluchtete der Herkunftsländer Syrien, Afghanistan, Irak und Eritrea und verdeutlicht den großen Anteil von Familien mit kleinen Kindern unter den nach Deutschland Gefluchteten. Daten zur Nutzung von Kinderbetreuungseinrichtungen von Kindern gefluchteter Familien zeigen, dass institutionelle Kinderbetreuung wesentlich zur Integration und Bildung beitragen kann. Der Wissenschaftliche Beirat für Familienfragen des BMFSFJ versucht, diesen für die Integration zentralen Aspekt in den Diskurs zu Flüchtlingen einzubringen und evidenzbasierte Handlungsempfehlungen zu geben.
Abstract in English:
Since 2015, many refugees have moved to Germany. So far, scholarly and political interests have focused on the possibilities of their labour market integration. However, the well-being and living arrangements of refugee families have been less investigated. This paper provides family-demographic data on refugees from Syria, Afghanistan, Iraq and Eritrea, and illustrates the high proportion of families with young children among them. The literature review of
refugee families’ usage of public funded day care demonstrates the potential of positive effects of early childhood education and care services on the integration and education of refugee children. The Scientific Advisory Board of the German Federal Ministry for Family Affairs, Senior Citizens, Women and Youth aims to bring this important issue for integration into the discourse on refugees and to provide evidence-based policy advice
Deutschland und die Stabilität der Wirtschafts- und Währungsunion
No full textIn der Gründungsphase der Währungsunion konzentrierten sich die deutschen Forderungen auf niedrige Inflationsraten und geringe Staatsverschuldung. Mit Beginn der Krise wurde jedoch deutlich, dass der deutsche Stabilitätsgedanke sehr eng gefasst war. Neben der fehlenden Haushaltsdisziplin trugen andere Faktoren maßgeblich zur Instabilität der Eurozone bei: Sowohl Leistungsbilanzungleichgewichte, als auch das Fehlen von Instrumenten zum Krisenmanagement und die gefährlichen selbstverstärkenden Dynamiken zwischen geschwächten Banken und überschuldeten Staaten wurden vor der Krise weitgehend ignoriert.
Im Verlauf der Krise hat die deutsche Regierung an ihrer traditionellen Vorstellung von Stabilität durch Kontrolle und Überwachung der Mitgliedsstaaten festgehalten. Zugleich hat Deutschland auch immer wieder pragmatisch gehandelt, um die Eurozone zu erhalten. So war das Land maßgeblich an der Schaffung des Europäischen Stabilitätsmechanismus und dem Aufbau einer Bankenunion beteiligt und tolerierte eine Reihe von außergewöhnlichen Maßnahmen der EZB.
Trotz der Reformbemühungen der letzten Jahre weist die Eurozone weiterhin Konstruktionsfehler auf, die die Stabilität der gemeinsamen Währung ernsthaft gefährden. Unter den Mitgliedsstaaten herrscht jedoch Uneinigkeit über die richtige Euro-Architektur: In der aktuellen Reform-Debatte prallen unterschiedliche Wahrnehmungen der Probleme und unterschiedliche politische Präferenzen für die Zukunft der Eurozone aufeinander. Die deutsche Europapolitik sollte sich um eine konstruktive Rolle in den notwendigen anstehenden Reformen bemühen. Hierbei gilt es auszubuchstabieren, unter welchen Umständen eine erhöhte Risikoteilung in der Eurozone für Deutschland tragbar wäre
How Does Differentiated Integration Work in the EU Financial Sector? Spotlight on Banking Union
No full textFive years after the entry into force of the Banking Union, this Policy Paper assesses its effectiveness as a form of differentiated integration. This case study presents the legal and organisational dimensions of the Banking Union and describes its accountability mechanisms and procedures. At the heart is the question of whether the creation of the Banking Union has been effective in promoting integration among its members
while avoiding distortions in the Single Market. To this end, also the impact of the Banking Union on the political unity in the European Union is analysed. This Policy Paper finds that the Banking Union has enhanced European integration in the financial sector without jeopardising the functioning of the internal market. Although the Banking Union is still incomplete, the benefits of participation create centripetal forces that are attractive also to non-euro countries
Growth and Welfare in Advanced Capitalist Economies
No full textGrowth and Welfare in Advanced Capitalist Economies takes stock of the major economic challenges that advanced industrial democracies have faced since the early 1990s and the responses by governments to them. It has three goals: firstly, to further our understanding of how political economies have transformed over the past decades; secondly, to analyse the contribution of governments to these changes, by looking at their growth strategies and thirdly, to highlight and analyse the role of the reforms of welfare systems in this transformative change.
In a nutshell, this book maps and provides general understanding of the evolution of growth regimes in advanced capitalist countries. It identifies five main growth regimes in contemporary advanced capitalist economies (three export-led and two domestic demand-led ones). To do so the book combines a supply side approach to economic growth as advocated by the Varieties of Capitalism Literature (OUP, 2001) with a demand side perspective as the recent discussion on growth models has exemplified. It argues that all political economies consist of growth regimes, which are based on a set of institutions that shape the supply side of the economy as well as on demand drivers such as government spending and private consumption. Both supply and demand are heavily shaped by the welfare state which provides for skills through education systems and stimulates demand through high social spending and private pension funds. The book focuses on the analysis of welfare reforms as growth strategies pursued by governments in an era characterised by financialization and the rise of the knowledge economy
