Das Spannungsverhältnis von Unklarheitenregel und Transparenzgebot — insbesondere bei Allgemeinen Versicherungsbedingungen

The text deals with the relation of § 305c Abs. 2 BGB (contra proferentem rule) and § 307 Abs. 1 S. 2 BGB (transparency control) especially in terms and conditions of insurance contracts. The author demonstrates that the contra proferentem rule is a special rule for ambiguous standard terms and conditions that is of higher priority than the transparency control.     

Letter to the editor on some frequently occurring errors in the economic literature concerning problems of maxima and minima

This paper points out some rather elementary mathematical errors perpetuated in textbooks.     

Maturity cycles in implied volatility

The skew effect in market implied volatility can be reproduced by option pricing theory based on stochastic volatility models for the price of the underlying asset. Here we study the performance of the calibration of the S&P 500 implied volatility surface using the asymptotic pricing theory under fast mean-reverting stochastic volatility described in [8]. The time-variation of the fitted skew-slope parameter shows a periodic behaviour that depends on the option maturity dates in the future, which are known in advance. By extending the mathematical analysis to incorporate model parameters which are time-varying, we show this behaviour can be explained in a manner consistent with a large model class for the underlying price dynamics with time-periodic volatility coefficients.Received: December 2003, Mathematics Subject Classification (2000): 91B70, 60F05, 60H30JEL Classification: C13, G13Jean-Pierre Fouque: Work partially supported by NSF grant DMS-0071744.Ronnie Sircar: Work supported by NSF grant DMS-0090067. We are grateful to Peter Thurston for research assistance.We thank a referee for his/her comments which improved the paper.     

The impacts of innovations and standards on trade of measurement and testing products: empirical results of Switzerland’s bilateral trade flows with Germany, France and the UK

Nowadays, the impact of the measurement and testing infrastructure on economic performance and trade is theoretically and even politically widely accepted. However, there are no empirical studies on this issue. The purpose of this paper is to elucidate the impact of innovative capacity and technical standards as one important part of the measurement and testing infrastructure on international trade flows and competitiveness. In order to focus on the direct causality between innovative technology and measurement and testing standards and the respective market, the empirical analysis concentrates on the trade of measurement and testing products of a country with a top position in measurement and testing technology. In its empirical analysis of Switzerland’s trade flows with Germany, France and the UK, the paper follows the approach of the pioneering paper of Swann et al. (Economic Journal 106 (1996) 1297), who integrated for the first time technical standards as a technology indicator in the estimation of UK trade performance. The trade flows in measurement and testing products from 1980 until 1995 are explained by both an indicator for innovative capacity and for the degree of standardisation. The first indicator is based on the patent applications at the European patent office. The latter uses the stocks of technical standards in the countries differentiated by their regional scope. Four different trade equations are analysed, besides an export and an import function, the trade balance and the intra-industry trade. The results clearly show that both Switzerland’s innovative capacity and its stocks of standards are able to explain its export performance in the three countries. Secondly, especially the stocks of international standards in Switzerland have a positive impact on imports into Switzerland from the three countries, confirming their positive role for fostering trade in general. Thirdly, Switzerland’s export surplus concerning the three trade partners is positively affected by the stocks of international standards in Switzerland, which seem to be an important factor for international competitiveness. Finally, the results of the intra-industry model underline the common view of the general trade-fostering effect of even national standards in the case of the trade with the three countries.     

Mehr Sozialprodukt mit weniger Energie: Es gibt nichts umsonst!

Economic growth guarantees prosperity and employment. In the interest of climate protection Germany is also aiming to significantly reduce its energy consumption. The Federal Government is committed to increase the real gross domestic product by 26 % between 2006 and 2020 and to reduce primary energy consumption in the same period by 17 %. Although long-term economic growth is possible with falling energy consumption, it does imply changes: structural changes and investments, which will initially require funding. In a simple model, it can be shown that the government’s ?hyper-decoupling“ of economic growth from energy demand will lead to an increase in the overall expenditure resulting from energy consumption between 2006 and 2020 of more than 60 % (the optimistic scenario) or 150 % (the less optimistic scenario). The accelerated use of modern energy technologies can help to set in motion the desired process to protect the environment and, at the same time, limit the resulting burden on the consumer. Here the intensified support of research and development of modern technologies will play an important role.     

Pacioli's Example Entries—a Conundrum Resolved?

This paper discusses the nature of the 10 example paragraph entries at the end of Pacioli's bookkeeping treatise. It concludes that these are entries from fledgling banking operations involving one account holder and one borrower who, along with two others, has financial transactions with the account holder. The widely held assumption that they are examples of entries in the Ledger is set aside and it is concluded that, on the basis of the available evidence, they are examples of entries in a Ricordanze, a record book Pacioli described as being used to record items of this type.     

Entrepreneurship: Origins and returns

We examine the origins and outcome of entrepreneurship on the basis of exceptionally comprehensive Norwegian matched worker-firm-owner data. In contrast to most existing studies, our notion of entrepreneurship not only comprises self-employment, but also employment in partly self-owned limited liability companies. Based on this extended entrepreneurship concept, we find that entrepreneurship tends to be profitable. It also raises income variability, but the most successful quartile gains much more than the least successful quartile loses. Key determinants of the decision to become an entrepreneur are occupational qualifications, family resources, gender, and work environments. Individual unemployment encourages, while aggregate unemployment discourages, entrepreneurship.     

A Jump/Diffusion Consumption-Based Capital Asset Pricing Model and the Equity Premium Puzzle

This paper derives the equilibrium excess returns on risky assets in an exchange economy where the underlying exogenous uncertainty is a combination of a pure multidimensional jump process and a diffusion model. We derive closed-form solutions for the interest rate and the risk premiums on risky assets for a traditional class of separable utility indices. Our analysis demonstrates that when the underlying jumps of the aggregate consumption process are not negligible, then the traditional form of the consumption-based capital asset princing model need not hold and the asset risk premiums may be larger than predicted by the traditional CCAPM in continuous time, based on pure Itô diffusion processes. Our analysis suggests an explanation for the large estimates of the risk premiums reported in empirical tests of the single-beta CCAPM.     

Wage Formation,Regional Migration and Local Labour Market Tightness*

Empirical studies of regional wage formation and interregional migration routinely include the regional unemployment rate as indicator of local labour market tightness. However, these studies are usually motivated by economic theories that emphasize transition probabilities between unemployment and employment, and the unemployment rate is an imperfect proxy for these probabilities. We use a large micro data set to compute estimates of the rate of outflow from unemployment for 90 Norwegian travel‐to‐work areas. The outflow rates perform better than traditional measures of regional labour market tightness in panel data analyses of regional wages and interregional migration.     

The long road to publishing: A user-friendly exposé

The popular axiom which suggests that there are two certainties in life (namely, taxes and death) should be extended to include a third dimension for aspiring academics, that is publish or perish. The scholarly activity of academic enquiry and publishing the results of these endeavours is an inescapable pre-requisite for a successful academic career. While some academics are prolific publishers, others are not. For those who find publishing a convoluted soul-destroying experience, this paper provides an exposé of the publication process from an author's perspective. It illustrates that the refinement of academic papers for publication is a collaborative effort between authors, editors and referees. Further, it shows that, for authors, there is no substitute for focus, perseverance and hard work. Copies of the letters tabled in this discussion are intended to serve as a useful framework for those who feel alienated by the academic review process.