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In this paper, we expand upon a prior study [Surovell, T.A., Brantingham, P.J., 2007. A note on the use of temporal frequency distributions in studies of prehistoric demography. Journal of Archaeological Science 34, 1868–1877.] that explored the problem of taphonomic bias. Taphonomic bias refers to the tendency for younger things to be over-represented relative to older things in the archaeological record due to the operation of destructive processes like erosion and weathering. Using a database of radiocarbon dated volcanic deposits from Bryson, R.U., Bryson, R.A., Ruter, A. [2006. A calibrated radiocarbon database of late Quaternary volcanic eruptions. Earth Discussions 1, 123–124.], we develop an empirical model of taphonomic bias. In contrast to our prior study in which we modeled taphonomic bias as an exponential function wherein the likelihood of site loss remains constant through time, we argue that the probability of site destruction actually decreases with site age. We further demonstrate how this model can be used to correct temporal frequency distributions and extract demographic histories. We illustrate this approach using databases of radiocarbon dates from rockshelter and open-air sites in the Bighorn Basin, Wyoming, USA, and mammoths and humans in Siberia, Russia.  相似文献   
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From the Late Neolithic to the Early Copper Age on the Great Hungarian Plain (4500 BC, calibrated) a transformation in many aspects of life has been inferred from the archaeological record. This transition is characterized by changes in settlements, subsistence, cultural assemblages, mortuary customs, and trade networks. Some researchers suggest that changes in material culture, particularly the replacement of long-occupied tells with smaller, more dispersed hamlets, indicates a shift from sedentary farming villages to a more mobile, agropastoral society that emphasized animal husbandry and perhaps secondary products of domestication. In a previous study (Giblin, 2009), preliminary radiogenic strontium (87Sr/86Sr) isotope data from human dental enamel showed that Copper Age individuals expressed more variable isotope values than their Neolithic predecessors. These data provided support for the idea that Copper Age inhabitants of the Plain were acquiring resources from a greater geographic area, findings that seemed consistent with a more mobile lifestyle. In this article a larger sample from human and animal skeletal material is used to re-evaluate earlier work and shed new light on the transition from the Neolithic to the Copper Age in eastern Hungary. The expanded sample of strontium isotopes from human dental enamel shows that 87Sr/86Sr values are more variable during the Copper Age, but the change is more pronounced in the Middle Copper Age than in the Early Copper Age. These results, along with recently published complementary research, indicate that the transition from the Late Neolithic tell cultures of the Plain to the more dispersed Copper Age hamlets was more gradual than previously thought, and that the emergence of an agropastoral economy does not explain changes in settlement and material culture.  相似文献   
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Recent calls for updated approaches to the Irish-American historical experience recommend more systematic attention to complexities inherent in Irish immigration and settlement. They also seek further contextualisation of the history of the Irish in the USA within broader North American, transatlantic and global frameworks. The need to review and potentially reappraise longstanding, essentialist perspectives on Irish arrival and assimilation is equally evident. This article expands on foundational narrative histories of the Boston Irish to re-examine Famine-era settlement and contending agendas within spheres of religious affiliation and political activism. The character and evolution of Irish-American ethnic identity, and the tragic imprint of the Famine under consideration here pave the way for new readings of traditional orthodoxies. Collectively, they reveal Boston's Irish historical terrain to be more complex than the record currently suggests.  相似文献   
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Late Pleistocene Siberia was characterized by a unique mammoth-steppe biome. Two prevailing hypotheses exist to explain modern human dispersals in the Siberian mammoth-steppe. Upper Paleolithic human populations were either maintained continuously throughout the late Pleistocene or the peopling of this region resulted from multiple dispersal events. Past attempts at explaining the colonization process have resulted in culture-historical interpretations. This article uses lithic technological data from middle and late Upper Paleolithic sites in the Enisei River valley of south-central Siberia to explain human dispersals from a behavioral perspective. Technological provisioning and land-use strategies are reconstructed to help explain dispersal processes. Results of the study demonstrate that hunter–gatherers were using different adaptive strategies before and after the Last Glacial Maximum, indicating that multiple dispersal events shaped the peopling of Siberia.  相似文献   
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We report on the results of an experiment aimed at determining the effects of experience/aptitude, lithic reduction type (biface v. core), and flake size cut-offs on different rates of success in refitting studies. We found that experience matters, but that there can be large differences in aptitude for refitting; that cores are easier to refit than bifaces; and that the effort of refitting increases considerably for flakes smaller than 5–6 g. We propose the use of an asymptotic equation fit to a cumulative curve as a way to determine when a study has reached the point of diminishing returns for a given flake size cut-off, and to help determine differences in aptitude for refitting.  相似文献   
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Australian electoral systems have a history of malapportionment, designed to give added voting weight to rural and remote areas. However, by 2000, all Australian jurisdictions except Western Australia had adopted voting equality within specified tolerances. This paper provides a brief analysis of the Gallop Labor government's efforts to reform the Western Australian system, drawing primarily on interviews with key players involved in the debates, including parliamentary members of the political parties involved. Quotations in this paper are drawn from these interviews, which were conducted in August 2004.  相似文献   
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Abstract. Workers’ compensation reforms have been on the table in virtually every state over the last several years, and many states have launched comprehensive reforms. At least nine states undertook major reforms of their workers’ compensation systems in 2004 alone, and the reforms were driven largely by claims that higher workers’ compensation costs are driving away businesses and the employment that comes with them. This paper examines the relationship between workers’ compensation costs, as proxied by benefits/earnings, and employment across U.S. states and the District of Columbia from 1976 to 2000. Workers’ compensation costs are found to have a statistically significant negative impact on employment and wages, but the elasticities are very small, suggesting that workers’ compensation is not a likely cause of jobs woes in most states. Unemployment insurance appears to have an effect of similar magnitude. Medical cost inflation is found to be a significant factor in explaining movements in workers’ compensation costs over time.  相似文献   
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