Empirische Analyse des Einflusses der Überschussbeteiligung auf Neugeschäft und Storno

Recently, German insurers are becoming increasingly interested in assessing and modelling risks related to new business and lapses. The final report of a DAV (German actuarial association) working party on stochastic models for German life insurance companies, released end of 2005, includes some basic approaches for this purpose. However, so far no systematic empirical research has been carried out which provides evidence for an appropriate calibration of such models. This article contributes to closing the gap. It presents the main results of an empirical analysis on the influence of policyholders’ profit participation on new business and lapses based on data about 87 German life insurance companies from 1995—2004. Analyses of regression and correlation were performed for various definitions of the explanatory variable ?profit participation“ (more precisely: the spread to some average value) and with diverse reference parameters for new business and lapses, also considering different types of life insurance. Ultimately, the exploration scarcely yielded evidence for a significant general correlation between policyholders’ profit participation and new business or lapses. However, because of the individuality of life insurance business such an evaluation of historical data can certainly only be regarded as a building block for the overall picture, as is also explained in the paper in some more detail.     

Probability theory in fuzzy sample spaces

This paper tries to develop a neat and comprehensive probability theory for sample spaces where the events are fuzzy subsets of The investigations are focussed on the discussion how to equip those sample spaces with suitable -algebras and metrics. In the end we can point out a unified concept of random elements in the sample spaces under consideration which is linked with compatible metrics to express random errors. The result is supported by presenting a strong law of large numbers, a central limit theorem and a Glivenko-Cantelli theorem for these kinds of random elements, formulated simultaneously w.r.t. the selected metrics. As a by-product the line of reasoning, which is followed within the paper, enables us to generalize as well as to bring together already known results and concepts from literature.Acknowledgement. The author would like to thank the participants of the 23rd Linz Seminar on Fuzzy Set Theory for the intensive discussion of the paper. Especially he is indebted to Professors Diamond and Höhle whose remarks have helped to get deeper insights into the subject. Additionally, the author is grateful to one anonymous referee for careful reading and valuable proposals which have led to an improvement of the first draft.This paper was presented at the 23rd Linz Seminar on Fuzzy Set Theory, Linz, Austria, February 5–9, 2002.     

A network experiment in continuous time: The influence of link costs

In recent work on non-cooperative network formation star-shaped networks play an important role. In a particular theoretical model of Bala and Goyal (2000) center-sponsored stars are the only strict Nash networks. In testing this theoretical model, Falk and Kosfeld (2003) do not find experimental evidence that players select the center-sponsored star. Based on a slight modification of Bala and Goyal’s model, we design a network formation experiment in which, depending on link costs, periphery-sponsored stars and the empty network are the only strict Nash networks. We observe that almost all groups not only reach a strict Nash network once but also switch the center player in periphery-sponsored stars several times. The main innovation in our experiment is to use a continuous time framework which we believe to be a more realistic setting to study behavior in network formation situations and which makes coordination on stars much easier than simultaneous strategy adaptation in discrete time. Electronic Supplementary Material Supplementary material is available in the online version of this article at http://dx.doi.org/10.1007/s10683-006-9125-1. JEL Classification C72 · C92 · D81     

Disequilibrium dynamics in a simple macroeconomic model

The dynamic behavior of a simple macroeconomic disequilibrium model is analyzed in which consumers' changes in money holdings constitute the dynamic link between any two periods. It is shown that, under constant government consumption, a constant production function (no investment), and fixed prices and wages, stationary states of Keynesian unemployment are stable whereas those of repressed inflation are globally unstable. Possibilities of unemployment and output cycles are indicated for fixed wages as well as for some very simple class of wage and price adjustment mechanisms.     

Post Bretton Woods deviations from purchasing power parity in G7 exchange rates—an empirical exploration

Exchange rates have deviated substantially and idiosyncratically from purchasing power parity (PPP) since the breakdown of Bretton Woods. In this paper, a model incorporating both traditional PPP and financial market variables is constructed and tested on the US dollar's six G7 exchange rates during the floating rate era. Empirical tests show that the model's common set of variables—with consistent signs—can explain the divergent behavior of G7 exchange rates during 1973.2–90.2. Idiosyncracies are reflected in different subsets of the model's variables entering significantly into each exchange rate's regression; the existence of stable relationships is demonstrated by the equations' co-integration.     

Evaluating the risk of patent infringement by means of semantic patent analysis: the case of DNA chips

In this paper, we are going to present a method for detecting the risks of patent infringement by evaluating similarities between patent documents on the basis of semantic patent analysis. This approach enables the user to visualize similarities in the contents on a semantic patent map by means of multi‐dimensional scaling. The effectiveness of the semantic patent map has already been demonstrated by Dressler (2006) with regard to patents of seal technology, in which documents are commonly kept short and the extracted contents are concise. This paper will open out to the field of biotechnology, where patents can easily comprise several hundreds of pages. The method presented here conveys an interdisciplinary approach and combines computer‐aided natural language processing with domain‐specific expertise of biochemical processes. This is illustrated by an authentic case of infringement involving two manufacturers of DNA chips. Our experiment will show how the infringement case is visualized on a patent map based on semantic patent analysis. This experiment can be compared with the search for a needle in a haystack, the two competitive patents representing significantly conflicting ‘needles.’ From an approximate number of 4,000 patents in the current US Class 435/6, a set of patents was selected that included the ‘needles’ mentioned. This paper will point out how such mutual interference can be detected by way of semantic patent analysis, and what advice may be given to R&D managers who are faced with the risk of patent infringement.     

The diversity of forecasts from macroeconomic models of the US economy

This paper investigates the accuracy and heterogeneity of output growth and inflation forecasts during the current and the four preceding NBER-dated US recessions. We generate forecasts from six different models of the US economy and compare them to professional forecasts from the Federal Reserve??s Greenbook and the Survey of Professional Forecasters (SPF). The model parameters and model forecasts are derived from historical data vintages so as to ensure comparability to historical forecasts by professionals. The mean model forecast comes surprisingly close to the mean SPF and Greenbook forecasts in terms of accuracy even though the models only make use of a small number of data series. Model forecasts compare particularly well to professional forecasts at a horizon of three to four quarters and during recoveries. The extent of forecast heterogeneity is similar for model and professional forecasts but varies substantially over time. Thus, forecast heterogeneity constitutes a potentially important source of economic fluctuations. While the particular reasons for diversity in professional forecasts are not observable, the diversity in model forecasts can be traced to different modeling assumptions, information sets and parameter estimates.     

Wirkungen und Nebenwirkungen des EU/IWF-Rettungsschirms für verschuldete Euroländer

Begriffe wie Staatsbankrott, spekulative Attacke und Gef?hrdung des Euro werden im Zusammenhang mit den offensichtlichen Schuldenproblemen einiger Eurol?nder genannt. Sie sind aber ungenau. Für eine Analyse m?glicher Wirkungen des EU/IWF-Rettungsschirms und dessen aktuell diskutierter Ausweitung ist eine genaue Defi nition erforderlich. Ergebnis der folgenden Analyse ist: Spekulative Attacken auf Staatsanleihen k?nnten durch den Rettungsschirm durchaus abgewehrt werden — allerdings m?glicherweise einhergehend mit einer Abwertung des Euro.     

Too Many Cooks? Committees in Monetary Policy

How many people should decide monetary policy? In this article, we take an empirical perspective on this issue and analyze the relationship between the number of monetary policy decision makers and monetary policy outcomes. Using a new data set that characterizes central bank monetary policy committees (MPCs) in more than 30 countries from 1960 through 2006, we find a U‐shaped relationship between MPC size and inflation; our results suggest that the lowest level of inflation is reached at MPCs with an intermediate size of about five to nine members. Similar results are obtained for inflation variability. Other MPC characteristics also matter for monetary policy outcomes, though to a smaller degree. For instance, the membership composition of the MPC as well as the frequency of MPC membership turnover appears to affect economic variables.