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This article evaluates linkage quality achieved by various record linkage techniques used in historical demography. The author creates benchmark, or truth, data by linking the 2005 Current Population Survey Annual Social and Economic Supplement to the Social Security Administration's numeric identification system by social security number. By comparing simulated linkages to the benchmark data, she examines the value added (in terms of number and quality of links) from incorporating text-string comparators, adjusting age, and using a probabilistic matching algorithm. She finds that text-string comparators and probabilistic approaches are useful for increasing the linkage rate, but use of text-string comparators may decrease accuracy in some cases. Overall, probabilistic matching offers the best balance between linkage rates and accuracy.  相似文献   
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Cultural geography has a long and proud tradition of research into human–plant relations. However, until recently, that tradition has been somewhat disconnected from conceptual advances in the social sciences, even those to which cultural geographers have made significant contributions. With a number of important exceptions, plant studies have been less explicitly part of more-than-human geographies than have animal studies. This special issue aims to redress this gap, recognising plants and their multiple engagements with and beyond humans. Plants are not only fundamental to human survival, they play a key role in many of the most important environmental political issues of the century, including biofuels, carbon economies and food security. In this introduction, we explore themes of belonging, practices and places, as discussed in the contributing papers. Together, the papers suggest new kinds of ‘vegetal politics’, documenting both collaborative and conflictual relations between humans, plants and others. They open up new spaces of political action and subjectivity, challenging political frames that are confined to humans. The papers also raise methodological questions and challenges for future research. This special issue grew out of sessions we organised at the Association of American Geographers Annual Meeting in New York in 2012.  相似文献   
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Astronomical data issued from observatories find multiple uses on land, as well as on sea. Due to their structure and periodicity, scientific reviews are particularly adapted to peer review and sharing of data between astronomers as well as between astronomers and hobbyists. During the 19th century regional observatories first gather together professionals interested in the practical applications of the observations and later, under the influence of personalities such as Camille Flammarion, they bring together a larger non-professional audience. Being the epicentre of scientific exchange, the reviews have in the 20th century found their place on the websites of academic institutions as well as users forums.  相似文献   
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Excavations in 1988 revealed a stratigraphic sequence extending from the later Roman period to the twelfth century. Of particular interest and importance is a collection of Viking-Age metalwork which, with other material, sheds light on settlement in Carlisle before the arrival of the Normans in 1092.  相似文献   
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Homeless and street children are commonly portrayed in the academic and welfare literature as a prime category of ‘children at risk’. They have attracted world‐wide attention due to rising numbers in cities of the Western and developing world coupled with a discourse of childhood that ascribes risk to poor urban children unaccompanied by adults on the streets. This paper presents a critique of views about homeless and street children that rest upon an unhelpful blanket generalization of risk and, more specifically, that adopt polemical or categorical statements about homelessness as the most salient risk factor for poor health. Current research is distancing itself from a discourse that sets global characteristics for a ‘street lifestyle’, aiming instead to contextualize research on street children. Many studies have also questioned the stereotypical expectation that homeless children are the most vulnerable in deprived environments, arguing that poverty, not homelessness per se, carries the most significant risks to children's health. A risk discourse is unhelpful where it promotes a stereotype of vulnerability about children, resulting in further discrimination and social exclusion; it is most helpful when it focuses attention on ways to negotiate adverse situations. Some challenging academic and practical questions need to be raised regarding risk assumptions and risk assessment.  相似文献   
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