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A table is presented for the construction and selection of tightened-normal-tightened sampling scheme of type TNT-(n1, n2;c). Efficiency of TNT-(n1, n2;c) scheme over conventional single and double sampling plans is discussed.  相似文献   
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Concept modeling is presented as a way to describe and understand social situations. Concepts are developed from field data and supported by sets of exemplars drawn from the data which illustrate the various concepts. The computer is considered an essential tool for conducting this type of qualitative data analysis and displaying the resulting concept models. Two sample concept models are presented along with a discussion of how concept models can be related to teaching and learning, as well as to the nonlinear presentation of research results. Assessment of concept models is then considered. Three types of assessment are suggested: empirical, qualitative and quantitative.  相似文献   
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Projecting losses associated with hurricanes is a complex and difficult undertaking that is wrought with uncertainties. Hurricane Charley, which struck southwest Florida on August 13, 2004, illustrates the uncertainty of forecasting damages from these storms. Due to shifts in the track and the rapid intensification of the storm, real-time estimates grew from 2 to 3 billion dollars in losses late on August 12 to a peak of 50 billion dollars for a brief time as the storm appeared to be headed for the Tampa Bay area. The storm hit the resort areas of Charlotte Harbor near Punta Gorda and then went on to Orlando in the central part of the state, with early poststorm estimates converging on a damage estimate in the 28 to 31 billion dollars range. Comparable damage to central Florida had not been seen since Hurricane Donna in 1960. The Florida Commission on Hurricane Loss Projection Methodology (FCHLPM) has recognized the role of computer models in projecting losses from hurricanes. The FCHLPM established a professional team to perform onsite (confidential) audits of computer models developed by several different companies in the United States that seek to have their models approved for use in insurance rate filings in Florida. The team's members represent the fields of actuarial science, computer science, meteorology, statistics, and wind and structural engineering. An important part of the auditing process requires uncertainty and sensitivity analyses to be performed with the applicant's proprietary model. To influence future such analyses, an uncertainty and sensitivity analysis has been completed for loss projections arising from use of a Holland B parameter hurricane wind field model. Uncertainty analysis quantifies the expected percentage reduction in the uncertainty of wind speed and loss that is attributable to each of the input variables.  相似文献   
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The purpose of this paper is to consider the relation between commuting and the settlement structure, with particular attention to rural and nonmetropolitan areas. I examined commuting flows between metropolitan central cities, other metropolitan areas, nonmetropolitan places with more than 10,000 people, those with 2500–10000 people, and other rural areas. Despite the deconcentration of population, industry and trade that was especially marked in the 1970s, commuting in 1980 was predominantly toward larger places in the ruralurban hierarchy, and particularly from rural areas and the other metropolitan category to cities. Overall levels of commuting were high, and most were within either nonmetropolitan or metropolitan areas. Smaller nonmetropolitan places particularly had high proportions of both in- and out-commuters. Differences in commuting flows by gender, socioeconomic status and industry were small, but generally in the directions expected on the basis of prior research. The findings reveal a high degree of work-residence interdependence among settlement units in nonmetropolitan America, with social and economic differences in commuting flows representing an important aspect of community structure.  相似文献   
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The advent of thousands of Usenet groups on the Internet, covering a vast range of medical and welfare issues and ostensibly devoted to the mutual social support of participating members, has raised the potential for the development of new forms of 'virtual' health care. This article critically analyses the use by people with diabetes of one such Usenet group. It seeks to establish, first, the extent to which such a site provides some demonstrable measure of social support to its participants. This is approached by undertaking a structural analysis of the site to identify the extent of usage, and the nature of supporting interventions using a fivefold classification (instrumental, informational, esteem and social companionship and other). Second, the article attempts to identify any disparity between the lay health-knowledge in evidence and biomedical opinions proffered by the use of a panel of consultant diabetiologists. The results of the analysis suggest that the diabetes newsgroup provides an example of an active forum for largely well-informed participants who routinely use the media as an aid to the reflexive management of their medical condition. It also raises the prospect of a renegotiated relationship between medical knowledge and lay experience based upon shared learning  相似文献   
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Behavior coding is one technique researchers use to detect problemsin survey questions, but it has been primarily explored as apractical tool rather than a source of insight into the theoreticalunderstanding of the cognitive processes by which respondentsanswer survey questions. The latter is the focus of the currentinvestigation. Using data from a large study in which face-to-faceinterviews were taped and extensive behavior coding was done,we tested whether sets of respondent behavior codes could beused to distinguish respondent difficulties with comprehensionof the question from difficulties associated with mapping ajudgment onto the response format provided, and whether characteristicsof the survey questions and respondents could be used to predictwhen and for whom such difficulties would occur. Sets of behaviorcodes were identified that reflected comprehension and mappingdifficulties, and these two types of difficulties were associatedwith different question and respondent characteristics. Thisevidence suggests that behavior coding shows promise as a toolfor researchers studying the cognitive processes involved inanswering survey questions.  相似文献   
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