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91.
Christopher S. Fowler Nathan Frey David C. Folch Nicholas Nagle Seth Spielman 《Geographical analysis》2020,52(2):155-168
Scholars frequently use counts of populations aggregated into geographic units like census tracts to represent measures of neighborhood context. Decades of research confirm that variation in how individuals are aggregated into geographic units can dramatically alter analyses conducted with these units. While most researchers are aware of the problem, they have lacked the tools to determine its magnitude or its capacity to affect analytical results obtained using these contextual measures. Using confidential access to the complete 2010 U.S. Decennial Census, we can construct—for all persons in the U.S.—individual-specific contexts, which we group according to Census-assigned block, block group, and tract. We compare these individual-specific measures to the published statistics at each scale, and we then determine the degree to which published measures could be affected by how boundaries are drawn using a simple statistic, the standard deviation of individual context (SDIC). For three key measures (percent Black, percent Hispanic, and Entropy—a measure of ethno-racial diversity), we find that block-level Census statistics frequently contain a high degree of uncertainty meaning that they may not capture the actual context of individuals within them. More problematic, we uncover systematic spatial patterns in the uncertainty associated with contextual variables at all three scales. 相似文献
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Vangelis Tourloukis Nicholas Thompson Charalampos Garefalakis Panagiotis Karkanas George E. Konidaris Eleni Panagopoulou 《Journal of Field Archaeology》2016,41(1):68-83
We here report the first results from a systematic research project in Mani (Southern Greece), which includes survey and test excavations. Forty-six caves, rockshelters and open-air sites in lowland settings were surveyed. Geomorphological data were collected in order to assess how geological processes affect the preservation of sites and bias site distribution patterns. Artifacts manufactured from non-local rock indicate potential raw material transfers and suggest links among the different regions of Mani, related to mobility patterns. Our research in the Mani has nearly doubled the number of known Middle Palaeolithic sites from the region and confirmed that the peninsula has the strongest ‘Neanderthal signal’ identified to date in Greece. Almost all sites are located at coastal areas. Despite the influence of Pleistocene landscape dynamics, this distribution emerges as a persistent pattern, perhaps indicating a preference for coastal locations. The Neanderthal occupation of Mani can illuminate important aspects of Middle Palaeolithic adaptation in one of the southernmost coastal regions of Europe. 相似文献
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Nicholas G. Blurton Jones 《Reviews in Anthropology》2013,42(2):151-160
Winterhalder, Bruce, and Eric Alden Smith, eds. Hunter‐Gatherer Foraging Strategies: Ethnographic and Archaeological Analyses. Chicago: University of Chicago Press, 1982. x + 268 pp. including bibliography and index. $18.00 cloth, $7.50 paper. 相似文献
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Jonathan R. Adams Annita Antoniadou Chistopher O. Hunt Paul Bennett Ian W. Croudace Rex N. Taylor Richard B. Pearce Graeme P. Earl Nicholas C. Flemming John Moggeridge Timothy Whiteside Kenneth Oliver Anthony J. Parker 《International Journal of Nautical Archaeology》2013,42(1):60-75
The Belgammel Ram was found off the coast of Libya in 1964, and examined during 2008–9. The following techniques were used: surface non‐contact digitizing using a laser scanner, reflectance transformation imaging using polynomial texture mapping and hemi‐spherical harmonics, digital photogrammetry with dense surface modelling, structured light optical scanning, and X‐ray fluorescence analysis. For internal structure the ram was examined by X‐radiography and 3‐D X‐ray tomography. Metallurgical composition was studied by micro‐drilling and subjecting the samples to scanning electron microscope X‐ray micro‐analysis, micro X‐ray fluorescence and X‐ray backscatter. The lead isotope composition was analysed. The alloy has average percentage composition Cu = 86.9, Sn = 6.3, Pb = 6.6, and Zn = < 0.10. The Belgammel Ram is probably a Hellenistic‐Roman proembolion from a small military vessel or tesseraria. The archived data are at the Faculty of Engineering and Environment, Engineering Sciences, Material Data Centre, University of Southampton ( muvis@soton.ac.uk ). 相似文献
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Nicholas Buchanan 《History & Technology》2013,29(2):221-249
Following World War II, food technologists in the US participated in an Army‐led program to develop food irradiation technology. The program involved over 120 military, government, industrial, and academic institutions. Focusing on the MIT Department of Food Technology, I trace the networks that formed between these groups and their motivations for developing the technology. I argue that food irradiation was Cold War science directed towards the development of a consumer product, and that it highlighted the links between large‐scale military‐funded research and consumers' everyday lives. I suggest that researchers advocated for irradiation not because the technology produced better processed food, but because the development of the technology produced a number of valuable benefits for the researchers. These included increases in funding, materials, and prestige. 相似文献