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41.
Home renovation is generally asserted to be a highly effective means to increase residential energy efficiency and thereby contribute to climate protection from reduced energy consumption. As part of a larger package of measures in the residential sector, the German government is consequently providing financial support for home audits from recognized energy experts who provide advice on retrofitting options. To date, the question concerning the effectiveness these home audits has largely escaped empirical scrutiny. The present paper fills this void by providing evidence for considerable free-rider effects within the home audit program, yielding serious reservations with respect to both the effectiveness of the program and its fiscal costs. Moreover, given the substantial differences between the gross- and net effects of home audits that are revealed by this analysis, the program’s contribution to climate protection and thereby the central justification for the associated government outlays is called into question. The social benefit of the program emerges only from those retrofits that would not have been undertaken in the absence of the home audit.  相似文献   
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Replanning is often used to optimize results of an activity in an ever changing world. To address the challenge of preparing future engineers for success, a special course was created for all engineering freshmen of the Faculty of Engineering of the University of Porto, in Portugal. Presented as a case study, this special course underwent a careful replanning as a result of several years of experience in teaching practice alongside with a theoretical deepening in pedagogical and technological issues, under the aegis of the action-research methodology. Within the context of the case study course, the mentioned replanning was also based on a theoretical approach that clearly identifies teaching–learning-assessment methodologies that promote regulation from those that foster emancipation, using a specific instrument: a taxonomy of educational processes. The replanning was designed to globally boost results regarding the educational aims of the course such as furthering freshmen’s integration into work environment and preparing them for success by fostering transversal skills (needed for study and work). Technology is seen as a mean of education enrichment as well as a productivity tool. The introduced innovations include fun-but-educational activities, several types of assessment over time and specific technological tools which were critical for the educational impact/achievement of this course. Success is demonstrated by encouraging feedback from the stakeholders, high students’ classifications and a steady reduction in retention. It is advocated that large portions of the reasoning behind the replanning can be extrapolated to other courses.  相似文献   
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The main objective of this paper is to estimate the economic capital for covering the external fraud risk within a financial institution. This is a kind of operational risk which is due to acts of a type intended to defraud, misappropriate property or circumvent the law, by a third party. From the methodological point of view, we apply the Loss Distribution Approach (LDA), based on the Internal Operational Loss Database (IOLD) provided by a Spanish Saving Bank. More specifically, we asses the potential impact of the severity distribution on the Capital at Risk (CAR). In absence of normality, we try to adjust the Lognormal, Weibull and Exponential functions when modelling the severity of losses. As a result, we find a high divergence in terms of capital charge depending on the statistical model selected. In consequence, in order to obtain a realistic model, we highlight the relevance of the goodness of fit between the empirical and the theoretical distribution.  相似文献   
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This paper explores the patterns of citations among patents taken out by inventors in the U.S., the U.K., Francc. Germany and Japan. We find (I) patents assigned to the same firm are more likely to cite each other, and come sooncr than other citations; (2) patents in the same patent class are approxinlatcly 100 titlles as likely to cite each other as ydtents froin different patent classes, but there is not a strong time pattern to this effect; (3) patents whose inventors reside in the same country are typically 30 to 80% more likely to cite each other than inventors from othcr countrics, and these citations come sooner; and (4) there are clear country-specific citation tendencies, e.g., Japanese citations typically come sooner than those of othcr countries.  相似文献   
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The paper is a parametric and nonparametric analysis of past precipitation data. We analyze 90 years of daily precipitation data at the Sooke Reservoir in British Columbia, Canada, for evidence of climate change. We fit probability density functions (PDFs) to the data and find evidence of a structural break in the data generating process by using the Andrews-Ploberger test. To confirm this finding, we analyze higher moments of the distribution of precipitation and show that the PDFs have become more leptokurtic. The results show how the pattern of precipitation has changed.  相似文献   
49.
This paper explores the role of portfolio constraints in generating multiplicity of equilibrium. We present a simple financial market economy with two goods and two households, households who face constraints on their ability to take unbounded positions in risky stocks. Absent such constraints, equilibrium allocation is unique and is Pareto efficient. With one portfolio constraint in place, the efficient equilibrium is still possible; however, additional inefficient equilibria in which the constraint is binding may emerge. We show further that with portfolio constraints cum incomplete markets, there may be a continuum of equilibria; adding incomplete markets may lead to real indeterminacy.  相似文献   
50.
We analyse time-varying risk premia and the implications for portfolio choice. Using Markov Chain Monte Carlo (MCMC) methods, we estimate a multivariate regime-switching model for the Carhart (1997) four-factor model. We find two clearly separable regimes with different mean returns, volatilities, and correlations. In the High-Variance Regime, only value stocks deliver a good performance, whereas in the Low-Variance Regime, the market portfolio and momentum stocks promise high returns. Regime-switching induces investors to change their portfolio style over time depending on the investment horizon, the risk aversion, and the prevailing regime. Value investing seems to be a rational strategy in the High-Variance Regime, momentum investing in the Low-Variance Regime. An empirical out-of-sample backtest indicates that this switching strategy can be profitable, but the overall forecasting ability for the regime-switching model seems to be weak compared to the iid model.  相似文献   
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