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Hinführung – Vorlesungen – Prüfung


Via Leray-Schauder’s nonlinear alternative, we obtain the existence of a weak solution for a nonlocal problem driven by an operator of elliptic type in a fractional Orlicz-Sobolev space, with homogeneous Dirichlet boundary conditions.


We develop and analyze an intertemporal cost of living index (ICOLI), also referred to as lifetime cost of living or cost of life index. The ICOLI is a geometric weighted average of effective prices, derived from constrained consumer utility maximization. Effective prices are both, money valued marginal utilities of the final unit consumed, and present values of prices for future consumption. Using the concept of duration, we derive analytical elasticities of the ICOLI with respect to consumer prices and interest rates and show their impact on lifetime welfare of consumers. We also provide empirical evidence for Germany, compute an ex post time series of the ICOLI, and gauge the welfare effects of low interest rate scenarios. We find that the financial repression policy of the ECB since 2010 contributed to substantial losses in the purchasing power of money and led to lasting welfare losses for consumers in Germany, in particular for the cohorts of young consumers. The ICOLI complements conventional price and inflation statistics and could serve as a valuable information tool for monetary policy.


This paper takes a closer look at the consequences of using a market index as a proxy for the latent market return in the capital asset pricing model. In particular, the consequences of two major sources of misspecification are analyzed: (i) the use of inaccurate weights and (ii) the use of only a subset of the asset universe to construct the index. The consequences resulting from the use of a badly chosen market proxy reach from inconsistent parameter estimates to misinterpretation of test outcomes indicating the existence of abnormal returns.

A minimum distance approach of estimating the CAPM under measurement error is presented, which identifies the CAPM parameters by exploiting the cross-equation cross-sectional restrictions resulting from a common measurement error. The new approach allows for quantifying the impact of measurement error and for testing the presence of spurious abnormal returns. Practical guidelines are presented to mitigate potential biases in the estimated CAPM parameters.


We investigate sources of educational differences in smoking. Using a large German data set containing retrospective information on the age at smoking onset, we compare age-specific hazard rates of starting smoking between (future) low and high educated individuals. We find that up to 90 % of the educational differences in smoking develop before the age of 16, i. e. before compulsory schooling is completed. This education gap persists into adulthood. Further, we examine the role of health-related knowledge (proxied by working in health-related occupations) and find it hardly explains smoking decisions. Our findings suggest that (unobserved) factors determining both the selection into smoking and education are almost exclusively responsible for educational differences in smoking. Only small parts of the education gap seem to be caused by general or health-specific education. The effectiveness of education policy to combat smoking is thus likely limited.



The following article informs about the Micro Data Linking-Panel (hereafter MDL-Panel), a new firm 1 dataset, available since May 2018 via the Research Data Centre of the Federal Statistical Office and the Research Data Centre of the Statistical Offices of the Federal States (RDC) (Forschungsdatenzentren der Statistischen Ämter des Bundes und der Länder (2018a, 2018b). The dataset originates from two projects funded by Eurostat over the period 2014 to 2016 with the title “Micro data linking of structural business statistics and other business statistics” (MDL). The projects combined data of various business statistics for the reference years 2008 to 2013 and were aimed at offering new perspectives on business statistics topics, which are not addressed in the ordinary publication program. Furthermore, MDL served to gain insights about the involved methodological challenges of linked data in Official Statistics. The first chapter provides background information on the projects funded by Eurostat. Chapter 2 contrasts the contents of the MDL-Panel to other products available via the RDC. The third chapter describes the scope of the dataset and its content in more detail. The article closes with future prospects for the MDL-Panel.



In German business statistics the statistical unit, or firm, is currently referred to as the smallest legally independent unit which keeps accounts for commercial and/or tax purposes.