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81.
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   
82.
This study identifies “other information” in analysts’ forecasts as a legitimate proxy for future cash flows and examines its incremental role in explaining stock return volatility. We suggest that “other information” contains information about fundamentals beyond that reflected in current financial statements and reflects firms’ fundamentals on a more timely basis than dividends or earnings. Using standardized regressions, we find volatility increases when current “other information” is more uncertain and increases more in response to unfavorable news compared to favorable news. Variance decomposition analysis shows that the variance contribution of “other information” dominates that of expected-return news. The incremental role of “other information” is at least half of the effect of earnings in explaining future volatility. The results are more pronounced for firms with poor information environments. Overall, our results highlight the importance of including “other information” as an additional cash-flow proxy in future studies of stock prices and volatility.  相似文献   
83.
What are the costs and benefits of mandatory dividend rules? On the one hand, they make it harder for controlling shareholders to divert corporate assets. On the other hand, they reduce the internal funds available for firms to invest, possibly leading to the loss of valuable projects. To assess this trade-off, we look at investment and dividend decisions in a sample of public firms in Brazil. We show that a significant fraction of these firms use loopholes of Brazil's mandatory dividend rules to avoid paying dividends. And yet, the dividend rules are effective. They help explain why the average dividend yield in Brazil is higher than in the U.S., without making it harder for firms to invest.  相似文献   
84.
Momentum strategies of German mutual funds   总被引:1,自引:0,他引:1  
The existence of the momentum effect in stock returns has been documented for the US (e.g., Jegadeesh and Titman in J. Finance 48(1), 65–91, 1993) and many other national equity markets worldwide (e.g., Griffin et al. in J. Finance 58(6), 2515–2547, 2003). However, little is known about the active employment of momentum strategies among institutional investors outside the US. This paper provides first evidence of momentum behavior among German mutual funds. We find the fund trades to follow stock returns on an aggregated institutional level. Moreover, we detect significant momentum behavior among funds with a European and global equity focus, as well as among funds predominantly investing in Asia. In contrast, German funds do not seem to engage in momentum strategies when trading domestic stocks. While only half the funds in our sample trade in accordance with past returns, 66 % of the funds within the largest size quintile follow momentum strategies. Finally, we do not find momentum trading funds to outperform the other funds.  相似文献   
85.
This paper explains the German government's response to the financial, economic and fiscal crises. It covers the financial crisis in 2008 when banks were supported (SoFFin), the economic crisis in 2009, and the fiscal crisis of increasing state debts and budget deficits which caused the German government to cut spending (Sparpaket) in 2010. The author looks at the contents of the government's responses, but also at the political and administrative aspects of the government's decision-making processes.  相似文献   
86.
This paper investigates whether familiarity induced by ambiguity aversion can help explaining the local bias phenomenon among individual investors. Using geographic closeness as a proxy for investor familiarity, we find that investors pull out of (unfamiliar) remote stocks and pour into (familiar) local stocks during times of increased market uncertainty. Moreover, the magnitude of this ‘flight to familiarity’ increases in the spread of an investor's ambiguity (about expected returns) between local and remote stocks. Our results prove robust to a number of alternative explanations of local bias. Specifically, we rule out a ‘home-field advantage’, where investors are able to translate information advantages about nearby companies into excess returns on their local stockholdings. We conclude that individual investors’ local bias is induced by ambiguity aversion in the portfolio selection process rather than a trading strategy based on superior information about local companies.  相似文献   
87.
A version of the fundamental theorem of asset pricing is proved for continuous asset prices with small proportional transaction costs. Equivalence is established between: (a) the absence of arbitrage with general strategies for arbitrarily small transaction costs ${\varepsilon > 0}${\varepsilon > 0}, (b) the absence of free lunches with bounded risk for arbitrarily small transaction costs ${\varepsilon > 0}${\varepsilon > 0}, and (c) the existence of e{\varepsilon}-consistent price systems—the analogue of martingale measures under transaction costs—for arbitrarily small ${\varepsilon > 0}${\varepsilon > 0}. The proof proceeds through an explicit construction, as opposed to the usual separation arguments. The paper concludes comparing numéraire-free and numéraire-based notions of admissibility, and the corresponding martingale and local martingale properties for consistent price systems.  相似文献   
88.
This paper proposes a pragmatic, discrete time indicator to gauge the performance of portfolios over time. Integrating the shortage function (Luenberger, 1995) into a Luenberger portfolio productivity indicator (Chambers, 2002), this study estimates the changes in the relative positions of portfolios with respect to the traditional Markowitz mean-variance efficient frontier, as well as the eventual shifts of this frontier over time. Based on the analysis of local changes relative to these mean-variance and higher moment (in casu, mean-variance-skewness and mean-variance-skewness-kurtosis) frontiers, this methodology allows to neatly separate between on the one hand performance changes due to portfolio strategies and on the other hand performance changes due to the market evolution. This methodology is empirically illustrated using a mimicking portfolio approach (22 and 23) using US monthly data from January 1931 to August 2007.  相似文献   
89.
In this paper, we are going to present a method for detecting the risks of patent infringement by evaluating similarities between patent documents on the basis of semantic patent analysis. This approach enables the user to visualize similarities in the contents on a semantic patent map by means of multi‐dimensional scaling. The effectiveness of the semantic patent map has already been demonstrated by Dressler (2006) with regard to patents of seal technology, in which documents are commonly kept short and the extracted contents are concise. This paper will open out to the field of biotechnology, where patents can easily comprise several hundreds of pages. The method presented here conveys an interdisciplinary approach and combines computer‐aided natural language processing with domain‐specific expertise of biochemical processes. This is illustrated by an authentic case of infringement involving two manufacturers of DNA chips. Our experiment will show how the infringement case is visualized on a patent map based on semantic patent analysis. This experiment can be compared with the search for a needle in a haystack, the two competitive patents representing significantly conflicting ‘needles.’ From an approximate number of 4,000 patents in the current US Class 435/6, a set of patents was selected that included the ‘needles’ mentioned. This paper will point out how such mutual interference can be detected by way of semantic patent analysis, and what advice may be given to R&D managers who are faced with the risk of patent infringement.  相似文献   
90.
To determine appropriate levels of care and access, while maximizing quality and capital resources, a service distribution plan fully defines: How the organization will serve the market, How each of the system's operations will relate to other operations, How clinical resources will be organized and deployed, The financial impact of the service distribution plan on the overall organization.  相似文献   
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