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251.
This paper analyzes the social welfare effects of tax-benefit reforms in a framework integrating endogenous labor supply and unemployment. We adopt an ordinal approach to social welfare comparisons by searching for “socially desirable” reforms that would improve social welfare for an entire class of social welfare functions. In the model, there is a discrete distribution of individuals’ productivities and individuals are heterogeneous with respect to leisure preferences (or disability of work). Labor supply decisions are limited to the participation decision. Unemployment is modeled in a search and matching framework with individual wage bargaining. For the social welfare analysis, the model is calibrated for Switzerland. Starting from a situation with an unemployment benefit scheme, the introduction of in-work benefits is shown to be a “socially desirable” reform: it would be unanimously preferred to the current situation according to all social welfare functions based on the criteria of Pareto, anonymity, and the principle of transfers. This result holds for two different types of preference heterogeneity (leisure preferences or disability of work) and also for the case where job search effort cannot be monitored.  相似文献   
252.
We combine two datasets to examine whether the presence of banks affects the profitability and outreach of microfinance institutions. We find evidence that competition matters. Greater bank penetration in the overall economy is associated with microbanks pushing toward poorer markets, as reflected in smaller average loans sizes and greater outreach to women. The evidence is particularly strong for microbanks relying on commercial-funding and using traditional bilateral lending contracts (rather than group lending methods favored by microfinance NGOs). We consider plausible alternative explanations for the correlations, including relationships that run through the nature of the regulatory environment and the structure of the banking environment, but we fail to find strong support for these alternative hypotheses.  相似文献   
253.
In this paper, we analyze the impact of Financial Times Deutschland (FTD) news on stock prices and trading volumes. Based on a sample of all news about German DAX, MDAX, and SDAX companies published in the news section of the FTD between 2006 and 2010, our results show that articles that contain positive (negative) information are associated with significantly positive (negative) abnormal returns and abnormal trading volumes around their publication. Furthermore, our results show an initial underreaction to these articles and subsequent post-publication drift. Based on the inattention hypothesis, we show that high-attention news (proxied by abnormal trading volume) almost instantaneously moves stock prices to their new valuation levels, whereas the price adjustment process takes much longer following low-attention news. Our results also hold within multivariate regressions where we additionally control for stock-specific characteristics (e.g., institutional ownership, size, and price-to-book ratio) as well as other attention-grabbing events (as measured by ad hoc announcements and cover-page news articles). Finally, we show that results primarily hold in the non-crisis period.  相似文献   
254.
Germany’s energy turnaround is leading to an increasing integration of photovoltaics (PVs) throughout its distribution grid. To ensure safe grid operation in times of high solar radiation, PV plants must either be throttled back to comply with the feed-in limitation or store a portion of their excess electricity in batteries. This paper presents a grid-optimized operating strategy for PV storage systems based on a Fuzzy Logic Controller that reduces peak feed-in and thus also PV curtailment losses. The Fuzzy Logic Controller uses data on PV power surplus and battery charge level as input variables. To obtain good results, the set of numerical parameters of the membership functions is enhanced by evolutionary programming.The energetic assessment shows that even small electrical storage capacities (<<5?kWh) reduce curtailment losses considerably when using the grid-optimized operating strategy. The economic assessment shows that, in 2016, investments in PV storage systems with large PV plants and small batteries have small (positive) Internal Rates of Return. The system efficiency of the battery storage has a small impact on the profitability of PV storage systems, whereas the cycle stability and the electricity purchase price have a large impact. Moreover, there is an economic benefit for plant operators to switch from the simple to the grid-optimized operating strategy. Solar forecast inaccuracies and variations in load and generation profiles have a negligible impact on the performance of the control algorithm.  相似文献   
255.
Ignoring the effects of inflation in retirement planning can have severe consequences for an individual's future financial well-being. Yet, many pension funds do not communicate inflation-related information, presumably for the fear of reduced contributions once the members understand how low the “real” return on saving for retirement is. As an alternative prediction, the provision of inflation information could increase pension contributions, because it reveals possible pension shortfalls. In cooperation with a major German pension fund, we conduct a field experiment, in which we vary the inflation information provided to the fund members, to explore this important issue. Among all participants, we find mostly positive but insignificant effects of the inflation information on pension contributions. Among those participants who voluntarily changed their pension contributions after the experimental intervention, the provision of inflation information significantly raises the likelihood of increasing pension contributions.  相似文献   
256.
This paper tests the ‘Too-Big-to-Fail’ hypothesis that whether being designated as a global systemically important bank (G-SIB) has an impact on the credit default swap (CDS) price of the bank, thereby reducing its credit risk. We find surprising evidence that the CDS spreads of a bank increase (decrease) after the announcement of a higher (lower) capital surcharge. However, this effect is temporary, as the mean CDS spreads revert to preannouncement level, dropping sharply after the initial rise. These findings create a puzzle by implying that a higher capital surcharge requirement and more stringent regulation could outweigh the implicit subsidy advantages of being too-big-to-fail.  相似文献   
257.
Service innovations in retailing have the potential to benefit consumers as well as retailers. This research models key factors associated with the trial and continuous use of a specific self‐service technology (SST), the personal shopping assistant (PSA), and estimates retailer benefits from implementing that innovation. Based on theoretical insights from prior SST studies, diffusion of innovation literature, and the technology acceptance model (TAM), this study develops specific hypotheses and tests them on a sample of 104 actual users of the PSA and 345 nonusers who shopped at the retail store offering the PSA device. Results indicate that factors affecting initial trial are different from those affecting continuous use. More specifically, consumers' trust toward the retailer, novelty seeking, and market mavenism are positively related to trial, while technology anxiety hinders the likelihood of trying the PSA. Perceived ease of use of the device positively impacts continuous use while consumers' need for interaction in shopping environments reduces the likelihood of continuous use. Importantly, there is evidence on retailer benefits from introducing the innovation since consumers using the PSA tend to spend more during each shopping trip. However, given the high costs of technology, the payback period for recovery of investments in innovation depends largely upon continued use of the innovation by consumers. Important implications are provided for retailers considering investments in new in‐store service innovations. Incorporation of technology within physical stores affords opportunities for the retailer to reduce costs, while enhancing service provided to consumers. Therefore, service innovations in retailing have the potential to benefit consumers as well as retailers. This research models key factors associated with the trial and continuous use of a specific SST in the retail context, the PSA, and estimates retailer benefits from implementing that innovation. In so doing, the study contributes to the nascent area of research on SSTs in the retail sector. Based on theoretical insights from prior SST studies, diffusion of innovation literature, and the TAM, this study develops specific hypotheses regarding the (1) antecedent effects of technological anxiety, novelty seeking, market mavenism, and trust in the retailer on trial of the service innovation; (2) the effects of ease of use, perceived waiting time, and need for interaction on continuous use of the innovation; and (3) the effect of use of innovation on consumer spending at the store. The hypotheses were tested on a sample of 104 actual users of the PSA and 345 nonusers who shopped at the retail store offering the PSA device, one of the early adopters of PSA in Germany. Data were analyzed using logistic regression (antecedents of trial), multiple regression (antecedents of continuous use), and propensity score matching (assessing retailer benefits). Results indicate that factors affecting initial trial are different from those affecting continuous use. More specifically, consumers' trust toward the retailer, novelty seeking, and market mavenism are positively related to trial, while technology anxiety hinders the likelihood of trying the PSA. Perceived ease of use of the device positively impacts continuous use, while consumers' need for interaction in shopping environments reduces the likelihood of continuous use. Importantly, there is evidence on retailer benefits from introducing the innovation since consumers using the PSA tend to spend more during each shopping trip. However, given the high costs of technology, the payback period for recovery of investments in innovation depends largely upon continued use of the innovation by consumers. Important implications are provided for retailers considering investments in new in‐store service innovations. The study contributes to the literature through its (1) simultaneous examination of antecedents of trial and continuous usage of a specific SST, (2) the demonstration of economic benefits of SST introduction for the retailer, and (3) contribution to the stream of research on service innovation, as against product innovation.  相似文献   
258.
259.
Profiles of inventors' technological competence are a valuable source of information for decision-making in research and development (R&D) management, e.g. concerning inventor assessment, human resource development and R&D team-building. In the following exposition, a new method of inventor profiling will be put forward, which is based in particular on semantic patent analysis and multidimensional scaling. First, in the course of semantic patent analysis, specialized software, equipped with a natural language processor, reads the patent text transferring the contents into a subject–action–object–format (SAO). The extracted SAO structures are then used to create similarity matrices for patents or patent sets, respectively, according to a specific similarity value. Subsequently, an inventor competence map can be produced by means of multidimensional scaling.
The benefits of this method for R&D-related issues in human resource management will be illustrated by the example of a German mechanical engineering company. Two distinct types of profiles were generated and tested: (i) the profile of a single key inventor and (ii) a profile of key inventor sets. The single key inventor profile gives information on the range of competence, i.e. the homogeneity or heterogeneity of a certain inventor's competences, providing far more detailed insights than resorting to bibliographic data like international patent classification (IPC) classes or citations, whereas the latter kind of profile establishes the position of a certain key inventor in relation to others, helping to highlight specific groups of inventors and their domains. These results are clearly apt to support human resource management.  相似文献   
260.
We discuss a weighted estimation of correlation and covariance matrices from historical financial data. To this end, we introduce a weighting scheme that accounts for the similarity of previous market conditions to the present situation. The resulting estimators are less biased and show lower variance than either unweighted or exponentially weighted estimators. The weighting scheme is based on a similarity measure that compares the current correlation structure of the market to the structures at past times. Similarity is then measured by the matrix 2-norm of the difference of probe correlation matrices estimated for two different points in time. The method is validated in a simulation study and tested empirically in the context of mean–variance portfolio optimization. In the latter case we find an enhanced realized portfolio return as well as a reduced portfolio risk compared with alternative approaches based on different strategies and estimators.  相似文献   
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