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161.
We propose a new estimator of spatial autocorrelation of areal incidence or prevalence rates in small areas, such as crime and health indicators, for correcting spatially heterogeneous sampling errors in denominator data. The approach is dubbed the heteroscedasticity‐consistent empirical Bayes (HC‐EB) method. As American Community Survey (ACS) data have been released to the public for small census geographies, small‐area estimates now form the demographic landscape of neighborhoods. Meanwhile, there is growing awareness of the diminished statistical validity of global and local Moran’s I when such small‐area estimates are used in denominator data. Using teen birth rates by census tracts in Mecklenburg County, North Carolina, we present comparisons of conventional and new HC‐EB estimates of Global and Local Moran’s I statistics created on ACS data, along with estimates on ground truth values from the 2010 decennial census. Results show that the new adjustment method dramatically enhances the statistical validity of global and local spatial autocorrelation statistics.  相似文献   
162.
flowAMOEBA: Identifying Regions of Anomalous Spatial Interactions   总被引:1,自引:0,他引:1  
This study aims at developing a data‐driven and bottom‐up spatial statistic method for identifying regions of anomalous spatial interactions (clusters of extremely high‐ or low‐value spatial flows), based on which it creates a spatial flow weights matrix. The method, dubbed flowAMOEBA, upgrades a multidirectional optimum ecotope‐based algorithm (AMOEBA) from areal data to spatial flow data through a proper spatial flow neighborhood definition. The method has the potential to dramatically change the way we study spatial interactions. First, it breaks the convention that spatial interaction data are always collected and modeled between spatial entities of the same granularity, as it delineates the OD region of anomalous spatial interactions, regardless of the size, shape, scale, or administrative level. Second, the method creates an empirical spatial flow weights matrix that can handle network autocorrelation embedded in spatial interaction modeling, thus improving related policy‐making or problem‐solving strategies. flowAMOEBA is tested and demonstrated on a synthetic data set as well as a county‐to‐county migration data set.  相似文献   
163.
Vladimir Fock was a Soviet theoretical physicist who, from the 1930s, worked to prove that modern physics was compatible with the Marxist philosophy of dialectical materialism. In 1957, he went to Copenhagen, and a dispute over the interpretation of quantum mechanics began with Niels Bohr. Fock later claimed that he had found points of convergence with his Danish colleague, most of them concerning issues of wording and recognition of the reality of the world independently of our mind. It led to a specific narrative among historians of physics on Fock and his interpretation of quantum mechanics: The Soviet physicist is often described as a member of the Copenhagen school that contributed to the rapprochement of the Soviet philosophy of physics with the ideas of complementarity in stripping away the positivism in its formulation. Our contribution aims to show that this ideological dimension was only one aspect of reality. Returning to the foundations of Fock's epistemology of physics, we argue that he relied on the principles of antireductionism and scientific realism to develop an interpretation of the theory that sought to overcome Bohr's approach and that the differences between the two men cannot be reduced to mere questions of formulation.  相似文献   
164.
This article seeks to refocus some of the attention devoted in the past several decades to the issue of food security in sub-Saharan Africa to the broader context of food dependency. Using panel data for 44 countries over a period of 51 years (1961–2011), the article tests several hypotheses drawn from Lewis's classical model of development characterized by ‘unlimited supplies of labour’. The model requires either rising agricultural productivity (the closed model) or imports of global market foodstuffs (the open model) to ensure the low food prices and wages required for capital accumulation. Empirical results reject a positive association between food dependency, as represented by five decades of increasing per capita grain imports, and any measurable level of economic modernization with sufficient forward momentum to spur or justify such dependency. Results suggest instead a significant correlation between increasing food dependency and separate panel time periods associated with differing trade and policy regimes. More importantly, empirical results call for a re-evaluation of Lewis's original development model, focusing on the pivotal role of a supported food subsistence sector in creating economic possibilities for development.  相似文献   
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The object of this article is to analyze the birth of literary history defined as the awareness of an evolving body of a nation's works and writers. Note is taken of the part played in the process by monarchical power, which saw in its role as guardian of the country's culture a means of asserting legitimacy, and attention is given to the evolution of the status of writers and their idea of their mission.

To illustrate his thesis, the author examines the publication in 1733 of the Histoire littéraire de la France by the Benedictine monks of Saint Maur. He defines its aims and its approach, demonstrates therein the emerging sense of a national culture and discusses the project's political implications. The commercial failure of the Histoire littéraire belies its overall importance, for the movement it effectively began led to the compulsory teaching of literary history in the place of rhetoric, to the establishment of a national pantheon of writers and to confrontations and concerns whose significance far surpassed the mere accumulation of a body of knowledge.  相似文献   
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During the Neolithic, obsidians of the Monte Arci (Sardinia) volcanic complex were by far more used in the northern Tyrrhenian area than those of the three other source-islands (Lipari, Palmarola, Pantelleria) in the western Mediterranean. It is shown that merely determinations of content for six major elements with a scanning electron microscope by energy dispersion spectrometry (SEM-EDS) are sufficient to distinguish the four types of Monte Arci obsidians. Because of the compositional similarities between these obsidian types, a multivariate analysis is recommended in provenance studies. Although SEM-EDS, electron microprobe-wavelength dispersion spectrometry (EMP-WDS) and particle induced X-ray emission (PIXE) give essentially concordant results in the determination of these six element contents, subtle technique-related biases prevent the combination of SEM-EDS, EMP-WDS and PIXE data on source samples for provenance purposes. An SEM-EDS test-study reveals the first occurrence of obsidians of Lipari for the A Fuata Middle to Late Neolithic site of NW Corsica (north of Sardinia), in addition to the usual Monte Arci obsidians. Similar to EMP-WDS, the SEM-EDS technique requires only millimeter-sized fragments.  相似文献   
170.
In 2014, the Joint United Nations Programme on HIV/AIDS set the target of dramatically reducing the burden of HIV through expansion of access to timely HIV treatment. In order to achieve this target, it is necessary to expand access to care along the HIV cascade of care. This study examines the relationship between viral suppression and the availability of physicians providing HIV treatment in British Columbia, Canada. Data from the Drug Treatment Program of the British Columbia Centre for Excellence in HIV/AIDS was analyzed. The floating catchment method was used to assess physician availability and multivariable logistic regression was used to implement a confounder selection technique to independently assess the relationship between physician availability and viral load suppression. Individuals with more than 25 physicians within a one‐hour catchment were more likely to reside in urban areas and almost twice as likely to have a suppressed viral load (adjusted odds ratio: 1.97; 95% CI 1.50 – 2.58). This study highlights the impact of physicians’ availability on viral load levels. Mapping technology was used to identify the locations in which patients were most impacted by the lack of physicians.  相似文献   
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