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71.
Price indices for heterogeneous goods such as real estate or fine art constitute crucial information for institutional or private investors considering alternative investment decisions in times of financial markets turmoil. Classical mean‐variance analysis of alternative investments has been hampered by the lack of a systematic treatment of volatility in these markets. In this paper we propose a hedonic regression framework which explicitly defines an underlying stochastic process for the price index, allowing to treat the volatility parameter as the object of interest. The model can be estimated using maximum likelihood in combination with the Kalman filter. We derive theoretical properties of the volatility estimator and show that it outperforms the standard estimator. We show that extensions to allow for time‐varying volatility are straightforward using a local‐likelihood approach. In an application to a large data set of international blue chip artists, we show that volatility of the art market, although generally lower than that of financial markets, has risen after the financial crisis of 2008–09, but sharply decreased during the recent debt crisis. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   
72.
Shortly before the decision of the Electricity Market Law on June 22, 2016 took place, the Federal Ministry for Economic Affairs and Energy (BMWi) changed its mind with respect to the procurement of new power plants for the German grid reserve. Other than originally planned, this is no longer organized via a competitive bidding process. Instead, the responsibility for the procurement will be transferred to the transmission system operators, which therefore face the challenge of implementing an appropriate procurement mechanism. This paper presents an economic explanation for this short-term change. Our analysis reveals that the proposed transfer of the concept for the procurement of spare capacity to the procurement of the grid reserve was not appropriate. The bidders would have been exposed to significant risks, in particular due to high cost and calculation uncertainties, which are also critical with respect to the achievement of the objectives of the grid reserve. Therefore, we consider the decision of refusing the original procurement concept as the right step, although we consider a competitive procedure advantageous. However, such a procedure has to take the special requirements of the grid reserve into account. Yet this problem remains even after the transfer of responsibility from the BMWi to the transmission system operators.  相似文献   
73.
If the supremum in the definition of the maximum likelihood test is replaced by the essential supremum, conditions for asymptotic optimality can be relaxed.This research was supported in part by NSF research grant number GP 31123X.  相似文献   
74.
This is one of the first comprehensive studies of drivers of private equity performance in the German‐speaking region known as the DACH, made up of Germany, Austria, and Switzerland. It contributes three things to private equity research: First, it explains how operational value drivers affect operational performance (operational alpha) and unlevered rates of return. Second, it whether the same relationships hold across different kinds of private equity business models (those with either organic or inorganic growth strategies; or whether PE investments are small‐cap or mid‐to‐large‐cap). Third, it distinguished between the periods before and after the global financial crisis of 2008. The authors found that (1) annualised benchmark‐adjusted EBITDA margin growth (i.e. improvement in EBITDA margin) is the most significant determinant in abnormal operational performance and unlevered returns, regardless of the business model; (2) private equity firms executing a buy‐and‐build strategy generate lower unlevered returns than those executing an organic growth strategy when the benchmark company is clearly outperformed, most likely because of limited PE managerial resources; (3) mid‐to‐large‐cap private equity firms generate higher unlevered returns and operational alphas than small‐cap private equity firms when the benchmark company is clearly outperformed, because, we believe, larger companies have a higher fixed cost leverage than smaller ones; and we have found that (4) buyout transactions exited during or after the financial crisis yield higher operational alphas but lower unlevered returns compared to buyout transactions exited before the crisis, when the portfolio company underperforms its benchmark company.  相似文献   
75.
Prior literature provides conflicting evidence about the impact of speculation on gold futures returns, volatility, and the relationship between market fundamentals and prices. In this paper, we exploit trade volume information to determine the most appropriate family of factors to adopt when modelling gold futures. Using the Disaggregated Commitment of Traders report, we find that extreme levels of speculation are informative in that they signify a shift in the relative modelling accuracy of macroeconomic and latent factors. A simple composite prediction framework, incorporating the changing level of speculation, empirically demonstrates the uncovered phenomenon and offers improved predictive accuracy for gold futures prices. Furthermore, our findings are shown to be robust to alternative latent and macroeconomic model specifications.  相似文献   
76.
Current e-commerce architectures rely on a small number of monolithic application systems. The adoption of innovative IT functionality within these architectures is a tedious and complex task. The purpose of this article is to present a design for a novel platform architecture to improve the pluggability of e-commerce services. More precisely, the pluggability of services in current architectures is described, a platform architecture is introduced, and its effect on pluggability is evaluated by means of a prototype. The enablers for this architecture are the recent innovations of web programming interfaces, delegated resource access, and client-side web application frameworks. Those technologies are common in social media and their potential in enterprise computing is revealed in this work, based on the example of a trade compliance service for cross-border retail. The results of this study suggest that the architectural design has merits as it improves the pluggability of e-commerce services. Hence, e-commerce companies should consider a paradigm shift and move from using self-contained application components to a platform-based adoption of complementary services.  相似文献   
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Modern silvicultural treatments are based on single trees whereas classic forest economics look at the stand level. To accompany each other it is necessary to transfer the established economic models to the single tree level. This paper is an approach to use the Faustmann model and the corresponding marginal rate of return (Pressler percent) to derive value increment rates of single trees taking into account neighbourhood effects due to competition between individual trees. Furthermore, optimal rotation periods and optimal final diameters for future trees will be calculated.  相似文献   
80.
Service firms face a unique set of challenges in their internationalization and foreign market growth. Their services' characteristics, particularly intangibility, constrain the options available to them for growth. When such firms are services International New Ventures (INVs), their challenges are combined with those related to rapid internationalization and growth. This research investigates how service intangibility and the typical challenges of INVs relate to the firms' Entrepreneurial Orientation and their foreign market growth. The findings show that indeed service intangibility has a relationship with firm proactiveness, risk-taking, and innovativeness; and that not all elements of Entrepreneurial Orientation have a positive impact on growth.  相似文献   
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