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101.
Quantitative risk assessments for physical, chemical, biological, occupational, or environmental agents rely on scientific studies to support their conclusions. These studies often include relatively few observations, and, as a result, models used to characterize the risk may include large amounts of uncertainty. The motivation, development, and assessment of new methods for risk assessment is facilitated by the availability of a set of experimental studies that span a range of dose‐response patterns that are observed in practice. We describe construction of such a historical database focusing on quantal data in chemical risk assessment, and we employ this database to develop priors in Bayesian analyses. The database is assembled from a variety of existing toxicological data sources and contains 733 separate quantal dose‐response data sets. As an illustration of the database's use, prior distributions for individual model parameters in Bayesian dose‐response analysis are constructed. Results indicate that including prior information based on curated historical data in quantitative risk assessments may help stabilize eventual point estimates, producing dose‐response functions that are more stable and precisely estimated. These in turn produce potency estimates that share the same benefit. We are confident that quantitative risk analysts will find many other applications and issues to explore using this database.  相似文献   
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Unemployment can pose particular problems for school leavers and other young people. Some English studies on the effects of unemployment are reviewed, and some of the causes and effects of unemployment among young people in Australia are then discussed. Some suggestions are made for areas in which further research could be carried out.  相似文献   
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Two potential problems in sex surveys—respondent refusalsand invalid reporting—are examined for national and areaprobability samples of males and females. Little support isfound for the contention that sexual topics constitute a sensitiveresearch area in terms of respondent cooperation and candor.It is found that (1) respondent cooperation, as indicated byrefusals and terminations, is neither more nor less problematicin sex research than in surveys on other topics; (2) respondentreports of sexual matters are not systematically related tointerviewer characteristics such as gender, sexual experience,or technical competence; (3) respondent candor, when self-reported,also is not associated systematically with either interviewercharacteristics or demographic and sexual characteristics ofrespondents. This analysis does identify, however, evidencethat (4) sexual matters often are sensitive topics for interviewersand principal investigators, leading both to interviewer turnoverand the creative construction of unobtrusive data collectionprocedures.  相似文献   
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A central premise of the industry change literature is that firms change their strategic actions when an industry changes. Industry convergence (IC), the blending of boundaries between industries creating competition among firms that previously did not compete, is increasingly impacting many industries and is a salient case of industry change. Acquisitions are an important action shaping the course of IC because they trigger imitation and bandwagon effects further accelerating IC. This paper focuses on why and when learning from alliances reduces uncertainty resulting in acquisitions during IC: an ‘alliance experience transfer effect’. We demonstrate the utility of this mechanism for the substitution‐based form of IC that occurred between the telecommunications equipment and computer networking industries. Our key insight is that when the extent of IC is low there are significant transfer effects but, as the extent of IC increases, firms have access to an expanding volume and diversity of information sources that reduce uncertainty, thus weakening the transfer effect mechanism. We contribute to the alliance–acquisition relationship and learning literatures by demonstrating that the alliance experience transfer effect mechanism explains changes in firm strategic action (alliancing and acquiring) as the extent of IC changes. We also introduce a semi‐convergence perspective by directly measuring the extent of IC.  相似文献   
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