In semiparametric models it is a common approach to under-smooth the nonparametric functions inorder that estimators of the finite dimensional parameters can achieve root-n consistency. The requirementof under-smoothing may result as we show from inefficient estimation methods or technical...

With the recent availability of high-frequency nancial data the longrange dependence of volatility regained researchers' interest and has leadto the consideration of long memory models for realized volatility. Thelong range diagnosis of volatility, however, is usually stated for long...

Systemic weather risk is a major obstacle for the formation of private (non-subsidized) crop insurance. This paper explores the possibility of spatial diversication ofinsurance by estimating the joint occurrence of unfavorable weather conditions in dierentlocations. For that purpose copula...

We consider two semiparametric models for the weight function in a biased sample model. The object of our interest parametrizes the weight function, and it is either Euclidean or non Euclidean. One of the models discussed in this paper is motivated by the estimation the mixing distribution of...

Normal distribution of the residuals is the traditional assumption in the classicalmultivariate time series models. Nevertheless it is not very often consistent with the real data.Copulae allows for an extension of the classical time series models to nonelliptically distributedresiduals. In this...

Modeling the portfolio credit risk is one of the crucial issues of the last yearsin the financial problems. We propose the valuation model of Collateralized DebtObligations based on a one- and two-parameter copula and default intensities estimatedfrom market data. The presented method is used to...

East German wages have been below the West German wage level since unification. Moreover, the East-West wage gap implied by the contractual wagesspecified in collective wage agreements is drifting ever further apart from the wagegap in terms of effective wages. This paper looks at the role of...

GARCH models are widely used in financial econometrics. However, we show by mean of a simple simulation example that the GARCH approach may lead to a serious model misspecification if the assumption of stationarity is violated. In particular, the well known integrated GARCH effect can be...

Graphical data representation is an important tool for model selection in bankruptcy analysis since the problem is highly non-linear and its numericalrepresentation is much less transparent. In classical rating models a convenientrepresentation of ratings in a closed form is possible reducing...