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Robert J. Hoard Steven R. Holen Michael D. Glascock Hector Neff J. Michael Elam 《Journal of archaeological science》1992,19(6)
Cryptocrystalline silicates from the Chadron Formation were widely used by prehistoric human groups in the Great Plains of North America. There are two documented quarry areas: Flattop Butte in Colorado and the White River Badlands of South Dakota. Cryptocrystalline silicates from these sources are visually indistinguishable, making it difficult to determine the sources of artefacts found at archaeological sites. In this investigation, neutron activation analysis is used to distinguish the two sources. This technique also identifies lithic material from the Clovis-age Eckles site in Kansas as being from Flattop Butte. 相似文献
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Research on policy impact has increasingly focused on the practical application of social science research. This paper outlines four roles—substantive expert, information processor, change agent, and scholar—which have helped to increase the potential usefulness of our research while maintaining linkages to the academic community. This paper suggests the general nature of these roles and suggests specific implementation strategies, which need to be pursued as an early and continuing aspect of the research enterprise. Balancing these multiple roles presents several analytical and ethical difficulties, but helps to establish credibility in both the scientific and policymaking communities. 相似文献
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It is argued that variation in uncertainty about social program goals and causal processes should influence the selection of evaluation designs and methods. Eighteen prominent evaluation reports are examined to contrast predicted evaluation strategies derived from theory about organizational uncertainty with the actual evaluation methods used. It was found that the actual design, measurement, and analysis procedures were frequently different from procedures that were compatible with the kinds of program uncertainty described in the evaluation reports. It is suggested that theory and practice in program evaluation can be improved by systematically incorporating organizational concepts that would contribute to the selection of evaluation methods. 相似文献