Exposition verhindern

Allergie durch Latex produkte - Nicht nur Pflegekr?fte leiden bisweilen an einer Latexallergie, auch Patienten k?nnen betroffen sein. Gerade bei Operationen, wenn latexhaltige Handschuhe, Katheter oder Beatmungsmasken direkten Kontakt zu Blut und Schleimh?uten des Patienten haben, ist das Risiko für Komplikationen hoch. Um schwerwiegende Notf?lle zu vermeiden, hilft oft nur eines – jegliche Latexexposition zu unterbinden.     

Class-size effects in school systems around the world: Evidence from between-grade variation in TIMSS

We estimate the effect of class size on student performance in 11 countries, combining school fixed effects and instrumental variables to identify random class-size variation between two adjacent grades within individual schools. Conventional estimates of class-size effects are shown to be severely biased by the non-random placement of students between and within schools. While we find sizable beneficial effects of smaller classes in Greece and Iceland, we reject the possibility of even small effects in four countries and of large beneficial effects in an additional four countries. Noteworthy class-size effects are observed only in countries with relatively low teacher salaries.     

Specifying Human Capital

A review of the measures of the stock of human capital used in empirical growth research – including adult literacy rates, school enrollment ratios, and average years of schooling of the working‐age population – reveals that human capital is mostly poorly proxied. The simple use of the most common proxy, average years of schooling, misspecifies the relationship between education and the stock of human capital. Based on human capital theory, the specification of human capital is extended to allow for decreasing returns to education and for differences in the quality of a year of education. The different specifications give rise to hugely differing measures of the stock of human capital across countries, and development‐accounting results show that misspecified human capital measures can lead to severe underestimation of the development effect of human capital.     

Sectoral and aggregate estimates of the cyclical behavior of markups: Evidence from Germany

Sectoral and Aggregate Estimates of the Cyclical Behavior of Mark-ups: Evidence from Germany. — The paper presents evidence of the cyclical behavior of the price to marginal cost ratio for Germany. Average markups are estimated both for two-digit manufacturing industries and for the aggregate economy, the results being quite similar once the difference between gross output and and value-added markups is accounted for. Over the business cycle, markups appear to be countercyclical for most parameter constellations. This is interpreted as empirical support for business cycle theories that rely on aggregate demand shocks to affect markups inversely, thus producing procyclical real wages and productivity without having to assume technology shocks.     

The effect of Protestantism on education before the industrialization: Evidence from 1816 Prussia

Across Prussian counties and towns, Protestantism led to more schooling already in 1816, before the Industrial Revolution. This supports a human capital theory of Protestant economic history and rules out a Weberian explanation of Protestant education just resulting from industrialization.     

Model uncertainty and VaR aggregation

Despite well-known shortcomings as a risk measure, Value-at-Risk (VaR) is still the industry and regulatory standard for the calculation of risk capital in banking and insurance. This paper is concerned with the numerical estimation of the VaR for a portfolio position as a function of different dependence scenarios on the factors of the portfolio. Besides summarizing the most relevant analytical bounds, including a discussion of their sharpness, we introduce a numerical algorithm which allows for the computation of reliable (sharp) bounds for the VaR of high-dimensional portfolios with dimensions d possibly in the several hundreds. We show that additional positive dependence information will typically not improve the upper bound substantially. In contrast higher order marginal information on the model, when available, may lead to strongly improved bounds. Several examples of practical relevance show how explicit VaR bounds can be obtained. These bounds can be interpreted as a measure of model uncertainty induced by possible dependence scenarios.     

DYNAMIC CDO TERM STRUCTURE MODELING

This paper provides a unifying approach for valuing contingent claims on a portfolio of credits, such as collateralized debt obligations (CDOs). We introduce the defaultable (T, x) ‐bonds, which pay one if the aggregated loss process in the underlying pool of the CDO has not exceeded x at maturity T, and zero else. Necessary and sufficient conditions on the stochastic term structure movements for the absence of arbitrage are given. Background market risk as well as feedback contagion effects of the loss process are taken into account. Moreover, we show that any exogenous specification of the volatility and contagion parameters actually yields a unique consistent loss process and thus an arbitrage‐free family of (T, x) ‐bond prices. For the sake of analytical and computational efficiency we then develop a tractable class of doubly stochastic affine term structure models.     

The effect of investment in children’s education on fertility in 1816 Prussia

The interaction between investment in children’s education and parental fertility is crucial in recent theories of the transition from Malthusian stagnation to modern economic growth. This paper contributes to the literature on the child quantity–quality trade-off with new county-level evidence for Prussia in 1816, several decades before the demographic transition. We find a significant negative causal effect of education on fertility, which is robust to accounting for spatial autocorrelation. The causal effect of education is identified through exogenous variation in enrollment rates due to differences in landownership inequality. A comparison with estimates for 1849 suggests that the preference for quality relative to quantity might have increased during the first half of the nineteenth century.     

The Supply of Safe Assets and Fiscal Policy

Beyond fleeting references, there is surprisingly little analysis about the interrelationship between fiscal policy and safe assets. This study analyses this interrelationship and argues that, at a certain point, more public debt will not “buy” more safety: countries face a kind of “safe assets Laffer curve”, with a maximum amount of safe assets at some level of indebtedness. The position and stability of this curve depend on a number of national and international factors, including international risk appetite and the quantitative easing policies implemented by central banks. The study also finds evidence of declining safe assets, as reflected in government debt ratings.     

Western industrial countries: brighter economic outlook,but world economy not out of the woods yet

Western industrial countries: brighter economic outlook, but world economy not out of the woods yet