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91.
There are some favorable signs. At this time of federal budget constraints, the EPA is tightening its belt. EPA's Science Advisory Council recognizes these fundamental constraints and urges the agency to consider relative risks to public health and the environment in establishing regulatory priorities. If Congress and EPA follow this informed advice, and consider honestly where medical waste fits into the spectrum of environmental risks, there is at least a chance that they could come up with a simple system--just enough to satisfy public opinion, but not enough to keep people from solving the problem.  相似文献   
92.
Although many hospital professionals now have personal access to online databases, popular communications services may not have the full range of electronic services needed for technical problem solving. Librarians are practiced at cross-disciplinary technical research and so health professionals may be best served by consulting an experienced database search analyst so that important information is not accidentally missed. Additionally, many commercially produced databases have repackaged and redistributed data developed by NIOSH and other federal agencies, data that are readily available in the public sector. The cost of accessing or purchasing commercial databases is usually higher than for federal databases, though commercial products use the federal databases to develop their products. Public agencies should always be consulted to obtain the most current information issued by those bodies and also because a variety of free and low-cost support materials may be available. Because of the expense of routinely consulting electronic databases when comparable printed materials may be available at a lower cost, a small reference collection of books, journals, and audiovisuals may be desirable. A selective print reference collection is found in Appendix A.  相似文献   
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94.
Burg B 《Medical economics》1993,70(19):40-2, 45-6, 48 passim
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95.
96.
Jackknifing Bond Option Prices   总被引:2,自引:0,他引:2  
Prices of interest rate derivative securities depend cruciallyon the mean reversion parameters of the underlying diffusions.These parameters are subject to estimation bias when standardmethods are used. The estimation bias can be substantial evenin very large samples and much more serious than the discretizationbias, and it translates into a bias in pricing bond optionsand other derivative securities that is important in practicalwork. This article proposes a very general and computationallyinexpensive method of bias reduction that is based on Quenouille's(1956; Biometrika, 43, 353–360) jackknife. We show howthe method can be applied directly to the options price itselfas well as the coefficients in the models. We investigate itsperformance in a Monte Carlo study. Empirical applications toU.S. dollar swap rates highlight the differences between bondand option prices implied by the jackknife procedure and thoseimplied by the standard approach. These differences are largeand suggest that bias reduction in pricing options is importantin practical applications.  相似文献   
97.
Frictions, Heterogeneity and Optimality in Mortgage Modeling   总被引:1,自引:0,他引:1  
The purpose of this article is to provide a unified framework for incorporating frictions into a theoretical options-pricing model (OPM) for mortgages. This article presents formulation for a frictions-adjustable mortgage model that integrates borrower heterogeneity while simultaneously preserving prepayment and default financial decisions. Our model demonstrates the flexibility of the OPM by simulating separate and concurrent effects of three categories of frictions on the mortgage and mortgage components. Researchers can use our example formulation to determine the effects of specific borrower characteristics on mortgage values without destroying the options theoretic framework.  相似文献   
98.
This study investigates the influence of the source of R&D funds and management ownership on R&D productivity. The lagged effect of the source of R&D funds on R&D output is investigated for a sample of US manufacturing firms in five industries over the 1996–99 period. Estimates based on 779 firm-years show that R&D productivity increases with the proportion of stock held by managers and directors of firms primarily in the Other Electronics industry. The estimates also show that recipients of government-sponsored R&D funds in the Chemicals industry have lower levels of output (sales) for each dollar committed to R&D. In addition, output for firms in the Chemicals industry worsens as management stockholding increases, implying an agency cost rationale for the observed difference in output. The implication is that firms with high manager-owner content are less productive with government-sponsored R&D than with company-financed R&D. The reported results suggest that potential agency costs should be incorporated in government-sponsored R&D contracts. It also suggests that the source of R&D funds should be disclosed and incorporated into the valuation of intangible assets attributable to research and development.  相似文献   
99.
This paper investigates the influence of industry uncertainty on the decision by established firms to enter a new industry. Specifically, we examine the tension between the option to defer , which discourages entry in the presence of uncertainty, and the option to grow , which may encourage entry in the presence of uncertainty when there are early mover advantages. Empirical analysis on data from a broad array of industries revealed that the effect of uncertainty on entry is not monotonic. Our findings are the first to find support for the nonmonotonic effect of uncertainty that has only recently emerged in theoretical treatments of real options theory, and amplify the importance of considering both the option to defer and the option to grow when contemplating entry. Furthermore, we found evidence that the relationship between uncertainty and entry is moderated by: (a) irreversibility, which influences the value of the option to defer; (b) the total value of growth opportunities; and (c) early mover advantages, which magnify the value of growth options. Copyright © 2003 John Wiley & Sons, Ltd.  相似文献   
100.
Advertised food specials may be deceptive to consumers who mistake the advertised prices as reduced prices. Of all the advertised food specials examined in this research, at least 13 percent and as many as 25 percent of those advertised in newspapers were not reduced in price.  相似文献   
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