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Recent contributions provide researchers with a useful toolbox to estimate counterfactual distributions of scalar random variables. These techniques have been widely applied in the literature. Typically, the dependent variable of interest has been a scalar and little consideration has been given to spatial factors. In this paper we propose a simple method to construct the counterfactual distribution of the location of a variable across space. We apply the spatial counterfactual technique to assess how much changes in individual characteristics of Hispanics in the Washington DC area account for changes in the distribution of their residential location choices. 相似文献
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Perhaps the greatest barrier to effective management of underwater cultural heritage is the lack of data on the nature and location of offshore archaeological resources. This is a problem shared with terrestrial archaeology, but is particularly acute due to the limitations of survey techniques in the underwater environment. In Scotland <15% of known ship losses from the last 200 years have been located and the record is far less comprehensive for earlier periods, verging on a near total data gap. Most known archaeological sites in Scottish waters have been discovered through large-scale sonar survey of relatively low resolution and a considerable bias has been introduced in the archaeological record; this has favored the discovery and documentation of larger and more recent, often upstanding, metal shipwrecks. This article presents the methods and results from a three-year project designed to reduce this bias by demonstrating large-scale prospecting for maritime archaeology through a community-based crowd-sourcing approach. Project SAMPHIRE (the Scottish Atlantic Maritime Past: Heritage, Investigation, Research and Education Project) was geographically focused on the west coast of the Scottish mainland and was undertaken between 2013 and 2015, resulting in a large number of new archaeological discoveries, including shipwrecks, aircraft, and other material of a much more varied nature than what is typically found through large-scale hydrographic surveys. 相似文献