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51.
Using two newly available ultrahigh-frequency datasets, we investigate empirically how frequently one can sample certain foreign exchange and U.S. Treasury security returns without contaminating estimates of their integrated volatility with market microstructure noise. Using the standard realized volatility estimator, we find that one can sample dollar/euro returns as frequently as once every 15 to 20 s without contaminating estimates of integrated volatility; 10-year Treasury note returns may be sampled as frequently as once every 2 to 3 min on days without U.S. macroeconomic announcements, and as frequently as once every 40 s on announcement days. Using a simple realized kernel estimator, this sampling frequency can be increased to once every 2 to 5 s for dollar/euro returns and to about once every 30 to 40 s for T-note returns. These sampling frequencies, especially in the case of dollar/euro returns, are much higher than those that are generally recommended in the empirical literature on realized volatility in equity markets. The higher sampling frequencies for dollar/euro and T-note returns likely reflect the superior depth and liquidity of these markets.  相似文献   
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53.
The paper refers to legal questions that arise in connection with the collection and use of genetic data in the context of private insurance. The content and meaning of § 18 GenDG is described. Then, § 18 GenDG is set in relation to notification requirements out of the VVG. The paper exemplarily emphasizes that, despite the codification of GenDG, specific legal problems arise. Accordingly, the paper provides solutions to overcome these problems. Particular problems refer to the role of genetic data of third parties and according relations to the family history, possibilities to communicate genetic data by the insured in case of medical indication, the ratio of predictive and diagnostic genetic testing and the range of the total limits of § 18 I 2 GenDG.  相似文献   
54.
This paper reconsiders the effect of investor sentiment on stock prices. Our main contribution is that, in addition to the intermediate term return predictability, we also analyze the immediate price reaction to the publication of survey‐based investor sentiment indicators. We find that the sign of the immediate market response is the same as that of the predictability at intermediate time horizons. This is consistent with underreaction to cash flow news or with investor sentiment being related to mispricing. It is inconsistent with the alternative explanations of a rational response to cash flow news or sentiment indicators providing information about future expected returns.  相似文献   
55.
Many companies experience difficult situations as a result of their selected strategy. Strategic management theories implicitly assume that companies have a free choice in setting their strategy. Hence, when companies experience difficult situations this is because of management inadequacy. It is questionable whether companies always have a free choice. This research examines this issue by examining the new product strategies of the two main competitors in the commercial aircraft industry. The development of the A380 aircraft was selected to determine to what extent the companies had a choice in setting their product development strategies. The conclusion is that neither has the alleged freedom for setting its strategy. Implications of this finding are that the strategy theory needs to be adjusted for this choice issue, and that management should not always be held fully responsible for the developing events.  相似文献   
56.
Based on an extension of the process of investors' expectations to stochastic volatility we derive asset price processes in a general continuous time pricing kernel framework. Our analysis suggests that stochastic volatility of asset price processes results from the fact that investors do not know the risk of an asset and therefore the volatility of the process of their expectations is stochastic, too. Furthermore, our model is consistent with empirical studies reporting negative correlation between asset prices and their volatility as well as significant variations in the Sharpe ratio.  相似文献   
57.
Innovation is generally recognized as a major source of economic growth. R&D investments explicitly aim at generating innovations and creating knowledge. Since knowledge has certain public good properties, positive externalities are likely to exist. In this paper, we extend well-known concepts from the input-output literature (backward multipliers) to indicate at which commodities stimuli should be targeted to enhance R&D and its positive externalities in the economy as a whole. Next, we argue that there may also be negative externalities of R&D, due to increased prices. This issue can be studied by means of forward multipliers. Both concepts are applied to the United States, 1977-90.  相似文献   
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59.
Conformity testing is a systematic examination of the extent to which an entity conforms to specified requirements. Such testing is performed in industry as well as in regulatory agencies in a variety of fields. In this paper we discuss conformity testing under measurement or sampling uncertainty. Although the situation has many analogies to statistical testing of a hypothesis concerning the unknown value of the measurand there are no generally accepted rules for handling measurement uncertainty when testing for conformity. Usually the objective of a test for conformity is to provide assurance of conformity. We therefore suggest that an appropriate statistical test for conformity should be devised such that there is only a small probability of declaring conformity when in fact the entity does not conform. An operational way of formulating this principle is to require that whenever an entity has been declared to be conforming, it should not be possible to alter that declaration, even if the entity was investigated with better (more precise) measuring instruments, or measurement procedures. Some industries and agencies designate specification limits under consideration of the measurement uncertainty. This practice is not invariant under changes of measurement procedure. We therefore suggest that conformity testing should be based upon a comparison of a confidence interval for the value of the measurand with some limiting values that have been designated without regard to the measurement uncertainty. Such a procedure is in line with the recently established practice of reporting measurement uncertainty as “an interval of values that could reasonably be attributed to the measurand”. The price to be paid for a reliable assurance of conformity is a relatively large risk that the procedure will fail to establish conformity for entities that only marginally conform. We suggest a two‐stage procedure that may improve this situation and provide a better discriminatory ability. In an example we illustrate the determination of the power function of such a two‐stage procedure.  相似文献   
60.
Despite evidence that information technology (IT) has recently become a productive investment for a large cross-section of firms, a number of questions remain. Some of these issues can be addressed by extending the basic production function approach that was applied in earlier work. Specifically, in this short paper we: 1) control for individual firm differences in productivity by employing a ‘firm effects’ specification, 2) consider the more flexible translog specification instead of only the Cobb-Douglas specification, and 3) allow all parameters to vary between various subsectors of the economy.

We find that while ‘firm effects’ may account for as much as half of the productivity benefits imputed to IT in earlier studies, the elasticity of IT remains positive and statistically significant. We also find that the estimates of IT elasticity and marginal product are little-changed when the less restrictive translog production function is employed. Finally, we find only limited evidence of differences in IT's marginal product between manufacturing and services and between the ‘measurable’ and ‘unmeasurable’ sectors of the economy. Surprisingly, we find that the marginal product of IT is at least as high in firms that did not grow during 1988–1992 sample period as it is in firms that grew.  相似文献   
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