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101.
Abstract. Which factors caused the growing international competitiveness of German mechanical engineering industry in the pre‐World War I period? In this paper, we want to address this question and elucidate whether or not the international market success of machine builders in the German Empire was determined by technological creativity and the availability of a comparatively cheap labour force. Based on an unbalanced panel, we therefore investigate the influence of demand, labour costs and technological creativity on export performance of 32 different machinery types. We find robust evidence that the development of export–import ratios in mechanical engineering was positively influenced by the growth of patent stocks that represent the new knowledge being available for German machine builders. In addition, we present some evidence for the assumption that the growing international competitiveness of German mechanical engineering was also caused by decreasing relative unit labour cost.  相似文献   
102.
Classic rangeland theory advocates stocking rangelands at relatively low and constant levels. This theory has been labelled inappropriate for savanna rangelands, because savannas are strongly influenced by stochastic processes. Opportunistic strategies that force animal numbers to track available forage have been proposed as an alternative management paradigm. However, no studies have examined whether these opportunistic strategies are sustainable or optimal. We developed a simulation model of a savanna rangeland to identify optimal, sustainable strategies for the management of extensive rangelands. We optimised the utility of agents who are motivated by economic, production or ecological factors under both deterministic and stochastic conditions. In all cases we found that it was optimal to manage the system conservatively and not opportunistically. Moreover, it was optimal to manage more conservatively under stochastic conditions. Key elements of the conservative strategy were to stock at low levels and to use fire to control tree abundance and thereby maintain the system in a grass dominated state. We conclude that opportunistic strategies of range management although intuitively appealing are not optimal.  相似文献   
103.
104.
Hedge fund returns have a number of specific features compared to traditional investments which result in problems when applying traditional methods of risk analysis (Markowitz portfolio selection theory, Sharpe Ratio, value at risk calculation based on normal returns). These problems have to be considered adequately by insurance companies when constructing internal risk models and performing risk management for hedge funds in their investment.The present paper has its focus on the departure of hedge fund returns from the normality hypothesis, especially with respect to the statistical quantities skewness and kurtosis (fat tail problem). A statistical analysis of hedge fund index returns gives evidence that the majority of hedge fund returns show substantial departures from normality. In addition, the analysis shows that hedge fund returns are adequately represented by the family of GH-distributions developed in exploratory data analysis. Following this result a risk analysis of hedge fund strategies is performed on the basis of the GH-value at risk.  相似文献   
105.
The German government has set ambitious goals for both the expansion of renewable energy supply and electromobility. According to its Energiewende policy, electricity supply from fluctuating renewables is supposed to further increase considerably. This will tend to require a greater provision of balancing reserves. At the same time, supply from conventional dispatchable plants, which used to provide the bulk of reserves, will decrease. Against this background, this article analyzes the scope for an assumed fleet of 4.4 million electric vehicles to supply balancing reserves in 2035. Examining two different future power plant scenarios, it explores the potentials of reserve provision with and without the option of feeding electricity from vehicle batteries back to the grid. Results from an extended open-source power system simulation model show that the assumed vehicle fleet can efficiently provide a substantial share of reserve requirements, also in case the vehicle-to-grid option is not available. Arbitrage on wholesale markets, on the other hand, is negligible under basic assumptions. Likewise, total system cost savings are minor when compared to a pure cost-optimal loading of vehicle batteries. Under alternative assumptions on the future power plant portfolio as well as on battery degradation costs, however, wholesale arbitrage, reserve provision, and system cost savings can be substantial.  相似文献   
106.
The article drafts a concept for applying the prohibition of indirect gender discrimination in the specific situation of insurance tariffs. In order to reveal indirect discrimination it has to be shown that each gender is affected differently by a differentiating factor to a significant extent. The basis is a statistical comparison between the total group and the disadvantaged subgroup (among potential insurance holders). Because of Art. 5 (1) of Council Directive 2004/113/EC a statistically verifiable risk difference cannot justify indirect discriminations by itself. The provision prohibits not only direct discrimination but also the use of differentiating factors highly correlated with one gender as the correlation leads to the inclusion of a higher gender-specific risk. Therefore only distinctions which are based on the individual insurance record can be justified as their aim is to influence future behaviour. In other cases it is necessary to separate the risk difference causally linked to the differentiating factor from the incorporated gender-specific risk difference.  相似文献   
107.
We investigate whether the financial accounting choices made by German private firms depend on legal form. Legal form determines dividend rights, liability status and the owners' obligations to run the business and, thus, influences agency problems of debt and equity. Consequently, we find that earnings properties depend on legal form. We expect, and find, that corporations exhibit higher levels of income smoothing and conservatism than partnerships and one-person businesses. Corporations are also more likely to disclose small profits. However, generally, there are no significant differences in earnings properties between one-person businesses and partnerships. The results are robust to different econometric specifications including endogeneity concerns (e.g. propensity score matching). Earnings properties of private firms seem to be driven to a considerable extent by agency problems of debt.  相似文献   
108.
Life‐cycle (or target‐date) funds are funds, which typically decrease their risk exposure over time. They have been very successful in many countries, particularly in the segment of old age provision. However, Expected Utility Theory (EUT) cannot explain their popularity. Moreover, recent results of Graf (2016), imply that not only EUT but also its behavioral counterpart Cumulative Prospect Theory (CPT) is often not able to explain the popularity of these products, since for each life‐cycle fund a corresponding balanced fund can be constructed, which is preferable from the investor's perspective in most circumstances. In a recent paper, Ruß and Schelling (2018), have argued that potential future changes in an investment's value already impact the decision of long‐term investors at outset. Based on this, they have introduced Multi Cumulative Prospect Theory (MCPT), which is based on CPT and considers the subjective utility generated by annual value changes. This paper shows that for MCPT‐investors, life‐cycle funds are typically more attractive than their corresponding balanced funds since they reduce the potential losses toward the end of the investment horizon. Hence, our findings provide an explanation for inferior decisions in old age provision. This can serve as a basis to improve such decisions.  相似文献   
109.
This article describes short-term reactions to the Asian crisis by European, US and Japanese MNCs and examines their long-term regional production strategies for Southeast Asia. In the process, it highlights similarities in the firms' responses but also distinguishes differences in the long-term regional reorganization of production activities of Western and Japanese firms. The article argues that there is currently a window of opportunity for Western MNCs to expand their Southeast Asian operations. Japanese firms face several obstacles to the implementation of a comprehensive regional production strategy as a result of their highly centralized way of managing international operations and their comparatively early production engagement in Southeast Asia whichequips most US and European MNCs with a latecomer advantage.  相似文献   
110.
Environmental planning aims to safeguard and foster the ecological functionality of agricultural landscapes. In order to reach a sustainable development of agricultural landscapes, in addition to ecological objectives socio-economic ones also need to be considered. In this context, the authors draw attention to three points. First, whenever ecologically sensitive areas (“ecological sites”) are used for agricultural production, it is necessary to take account of the fact that farmers tend to adapt to environmental requirements by production responses outside the ecological site itself. Second, in order to identify the socially most “desirable” land-use responses it is necessary to supplement the above-mentioned environmental objectives by socio-economic ones. Third, when choosing an appropriate model for such multi-criteria decision analysis, the question of substitutability between criteria is of utmost importance. The paper discusses the above-mentioned issues against the background of a case study of environmental planning for an ecologically very valuable agricultural landscape in Germany, the Bayerisches Donauried. Two models of multi-criteria decision analysis (MCDA) are applied, one based on the “single synthesizing criterion” method, and the other one based on the “synthesis by outranking” method. The models serve to evaluate four different land-use options, using criteria mainly derived from landscape functions and weights gained from interviews with major stakeholders. The paper presents the models’ results concerning the ranking of the different land-use options and discusses the implications for agri-environmental policies and rural development planning.  相似文献   
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