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The forecasting potential of complex models 总被引:2,自引:0,他引:2
William Ascher 《Policy Sciences》1981,13(3):247-267
The nature and use of complex models for forecasting and policy simulation are analyzed on theoretical and empirical-performance grounds. The analysis suggests that while the accuracy of complex models in forecasting trends in such fields as economic and energy is, and will remain, undistinguished, complex models' special virtues of preserving counter-intuitive results and representing subsystem interdepedence could be used to better advantage than current practice permits. Suggestions for such improvements, through more diversified model structures, micro-process models in addition to the typical macro models, a mix of mechanically- and judgmentally-operated models, and the modeling of policy response, are reviewed. 相似文献
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R G Evans 《Journal of health politics, policy and law》1983,8(1):1-43
During the 1970s the share of health care expenditure in Canadian GNP remained roughly stable, in the range of 7-71/2 percent of GNP, in marked contrast to its escalation in most other countries (the U.S. in particular) and to previous Canadian experience. The shift to a stable pattern coincided with the completion of the Canadian system of universal comprehensive public hospital and medical care insurance. This paper explores how and why the public insurance system served to contain cost escalation. It then discusses the inadequacy of expenditure experience per se as a basis for health system evaluation--the same data will support claims of both "underfunding" and "spiralling costs." More serious questions involve the influence of alternative patterns of health care funding and delivery on the effectiveness and efficiency of care provision, and the resulting distributional patterns of care and income. A brief sketch is given of the present situation and future possibilities of Canadian health care under these heads. 相似文献
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Linenberger P 《Labor law journal》1983,34(4):238-247
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H C Lee E M Pagliaro K M Berka N L Folk D T Anderson G Ruano T P Keith P Phipps G L Herrin D D Garner 《Journal of forensic sciences》1991,36(2):320-330
Deoxyribonucleic acid (DNA) was isolated from a number of spongy and compact human bone tissue specimens, and the yield was estimated on a "per milligram of starting tissue" basis. DNA was, in addition, isolated from a number of corresponding blood and bone tissue specimens. Spectrophotofluorometry and ethidium bromide visualization on minigels were used to estimate the quantity and degree of degradation of DNA. The DNA from several blood-bone pairs is shown to give concordant restriction fragment length polymorphism (RFLP) typing results by two different typing protocols with five different single-locus probes. DNA from several additional blood-bone pairs is shown to give concordant results for human leucocyte antigen (HLA)-DQ alpha phenotypes following polymerase chain reaction (PCR) amplification and hybridization to specific allele-specific oligonucleotide (ASO) probes, and for the variable numbers of tandem repeats (VNTR) length polymorphisms 3' to the human apolipoprotein B (APOB) gene following PCR amplification with specific primers and analysis of the products by electrophoresis and ethidium bromide visualization. 相似文献