**Eldorado**

Ressourcen aus und für Forschung, Lehre und Studium

### Aktuellste Veröffentlichungen

When analyzing what determines the efficiency of production, regressing efficiency scores estimated by DEA on explanatory variables has much intuitive appeal. Simar and Wilson (2007) show that this na¨ıve two-stage estimation procedure suffers from severe flaws, that render its results, and in particular statistical inference based on them, questionable. At the same time they propose a statistically grounded bootstrap based two-stage estimator that eliminates the above mentioned weaknes...

In this paper we introduce a robust to outliers Wilcoxon change-point testing procedure, for distinguishing between short-range dependent time series with a change in mean at unknown time and stationary long-range dependent time series. We establish the asymptotic distribution of the test statistic under the null hypothesis for L1 near epoch dependent processes and show its consistency under the alternative. The Wilcoxon-type testing procedure similarly as the CUSUM-type testing procedur...

This paper applies new econometric tools to monitor and detect so-called "financial market dislocations", defined as periods in which substantial deviations from arbitrage parities take place. In particular, we focus on deviations from the triangular arbitrage parity for exchange rate triplets. Due to increasing media attention towards mispricing in the market for cryptocurrencies, we include the cryptocurrency Bitcoin in addition to fiat currencies. We do not find evidence for substantial...

Biosimilars are copies of biological medicines that are developed by a competitor after the patent for the originator drug has expired. Extensive clinical trials are required to show therapeutic equivalence between the biosimilar and its reference product before a biosimilar can be sold on the market. However, even after more than 10 years of experience with biosimilars in Europe, there is still some uncertainty if the patients who are already taking the reference product can switch betw...

We propose completely nonparametric methodology to investigate location-scale modelling of two-component mixture cure models, where the responses of interest are only indirectly observable due to the presence of censoring and the presence of so-called long-term survivors that are always censored. We use covariate-localized nonparametric estimators, which depend on a bandwidth sequence, to propose an estimator of the error distribution function that has not been considered before in the litera...

The production of electricity on the basis of renewable energy technologies is a classic example of an impure public good. It is often discriminatively financed by industrial and household consumers, such as in Germany, where the energy-intensive sector benefits from far-reaching exemptions, while all other electricity consumers are forced to bear a higher burden. Based on randomized information treatments in a stated-choice experiment among about 11,000 German households, we explore wh...

Consider the problem of pointwise estimation of f in a multiple isotonic regression model Z = f(X1, ... ,Xd) + ε , where Z is the response variable, f is an unknown non-parametric regression function, which is isotonic with respect to each component, and is the error term. In this article, we investigate the behaviour of the least square estimator of f and establish its asymptotic properties. We generalize the greatest convex minorant characterization of isotonic regression estimator for...

This paper introduces test and estimation procedures for abrupt and gradual changes in the entire jump behaviour of a discretely observed Ito semimartingale. In contrast to existing work we analyse jumps of arbitrary size which are not restricted to a minimum height. Our methods are based on weak convergence of a truncated sequential empirical distribution function of the jump characteristic of the underlying Ito semimartingale. Critical values for the new tests are obtained by a multipl...

Biosimilars are medical products that are developed as copies of already established, large molecule drugs (biologics). For gaining approval, sponsors have to confirm that the proposed biosimilar has the same efficacy and safety as the originator product. This comparability exercise includes also, in most cases, that large clinical trials are conducted in patients. However, even with the evidence gained during the clinical studies, there is still some uncertainty if patients who were alr...

In this paper we propose a new approach for sequential monitoring of a parameter of a d-dimensional time series. We consider a closed-end-method, which is motivated by the likelihood ratio test principle and compare the new method with two alternative procedures. We also incorporate self-normalization such that estimation of the longrun variance is not necessary. We prove that for a large class of testing problems the new detection scheme has asymptotic level a and is consistent. The asy...

This paper considers the problem of testing if a sequence of means (μ t)t=1,...,n of a non-stationary time series (Xt)t=1,...,n is stable in the sense that the di fference of the means μ1 and μt between the initial time t = 1 and any other time is smaller than a given level, that is |μ1 — μt| ≤ c for all t = 1,..., n. A test for hypotheses of this type is developed using a bias corrected monotone rearranged local linear estimator and asymptotic normality of the corresponding test statistic ...

Although public support for renewable energy promotion in Germany is strong, the required power line construction has incited a groundswell of opposition from residents concerned about the impacts on their neighborhoods. This paper evaluates a large randomized one-shot binary-choice experiment to examine the effect of different compensation schemes on the acceptance of new power line construction. Results reveal that community compensations have no bearing on the acceptance level, where...

This paper extends the literature on predatory short selling and bailouts through a joint analysis of the two. We consider a model with informed short sales, as well as uninformed predatory short sales, which can trigger the inefficient liquidation of a firm. We obtain several novel results: A government commitment to bail out insolvent firms with positive probability can increase welfare because it selectively deters predatory short selling without hampering desirable informed short sa...

The issue of determining not only an adequate dose but also a dosing frequency of a drug arises frequently in Phase II clinical trials. This results in the comparison of models which have some parameters in common. Planning such studies based on Bayesian optimal designs offers robustness to our conclusions since these designs, unlike locally optimal designs, are efficient even if the parameters are misspecified. In this paper we develop approximate design theory for Bayesian D-optimality...

Dieser Artikel untersucht auf Basis einer Befragung von mehr als 5.000 Haushaltsvorständen, wie viel sie für Versorgungssicherheit mit Strom zu zahlen bereit sind. Alternativ zur Zahlungsbereitschaft (willingness to pay, WTP) wird auch nach der Bereitschaft gefragt, gegen eine Entschädigungszahlung auf ein gewisses Maß an Versorgungssicherheit zu verzichten (willingness to accept, WTA). In Übereinstimmung mit zahlreichen empirischen Studien finden wir mittlere WTA-Werte, die deutlich übe...

The assumption of separability is a simplifying and very popular assumption in the analysis of spatio-temporal or hypersurface data structures. It is often made in situations where the covariance structure cannot be easily estimated, for example because of a small sample size or because of computational storage problems. In this paper we propose a new and very simple test to validate this assumption. Our approach is based on a measure of separability which is zero in the case of separabi...

In this paper optimal designs for regression problems with spherical predictors of arbitrary dimension are considered. Our work is motivated by applications in material sciences, where crystallographic textures such as the missorientation distribution or the grain boundary distribution (depending on a four dimensional spherical predictor) are represented by series of hyperspherical harmonics, which are estimated from experimental or simulated data. For this type of estimation problems w...

Functional data analysis is typically conducted within the L2-Hilbert space framework. There is by now a fully developed statistical toolbox allowing for the principled application of the functional data machinery to real-world problems, often based on dimension reduction techniques such as functional principal component analysis. At the same time, there have recently been a number of publications that sidestep dimension reduction steps and focus on a fully functional L2-methodology. This pap...

In this paper we present a new method for determining optimal designs for enzyme inhibition kinetic models, which are used to model the influence of the concentration of a substrate and an inhibition on the velocity of a reaction. The approach uses a nonlinear transformation of the vector of predictors such that the model in the new coordinates is given by an incomplete response surface model. Although there exist no explicit solutions of the optimal design problem for incomplete respons...

We derive tests of stationarity for continuous univariate time series by combining changepoint tests sensitive to changes in the contemporary distribution with tests sensitive to changes in the serial dependence. Rank-based cumulative sum tests based on the empirical distribution function and on the empirical autocopula at a given lag are considered first. The combination of their dependent p-values relies on a joint dependent multiplier bootstrap of the two underlying statistics. Condit...

### Sammlungen in diesem Bereich

#### Sonderforschungsbereich (SFB) 475 [595]

Reduction of Complexity for Multivariate Data Structures

#### Sonderforschungsbereich (SFB) 531 [249]

Design und Management komplexer technischer Prozesse und Systeme mit Methoden der Computational Intelligence

#### Sonderforschungsbereich (SFB) 559 [64]

Modellierung grosser Netze in der Logistik

#### Sonderforschungsbereich (SFB) 823 [460]

Nichtlineare dynamische Modelle in Wirtschaft und Technik

#### Sonderforschungsbereich (SFB) 876 [49]

Verfügbarkeit von Information durch Analyse unter Ressourcenbeschränkung

#### Sonderforschungsbereich (SFB) Transregio 10 [0]

Integration von Umformen, Trennen und Fügen für die flexible Fertigung von leichten Tragwerkstrukturen