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41.
In this paper we investigate empirical relationships between Unemployment Insurance (UI) and welfare policies using a unique database covering 48 states annually from 1973 through 1989. We first document substantial variation across states in UI program outcomes. Having established that UI is so variable, we explore the simultaneous interaction between UI and Aid to Families with Dependent Children (AFDC), Medicaid, and total state and local welfare spending. Our econometric results indicate substitution between the two cash assistance programs, AFDC and UI, by state governments. On the other hand, states that operate relatively generous UI programs also tend to allocate more resources to Medicaid and other in-kind, low-income assistance programs. 相似文献
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From 'industrial districts' to 'knowledge clusters': a model of knowledge dissemination and competitive advantage in industrial agglomerations 总被引:6,自引:0,他引:6
Pinch Steven; Henry Nick; Jenkins Mark; Tallman Stephen 《Journal of Economic Geography》2003,3(4):373-388
This paper integrates knowledge-based theories of the firm withgeograph-ical studies of industrial agglomeration to producea model that helps explain the competitive advantages enjoyedby proximate firms located in geographical clusters. We proposea hierarchy of specialized knowledge stocks at both firm andcluster levels and suggest that the comparative advantage conferredby knowledge resources at each level is protected, in part,by asymmetries in knowledge flows from level to level. The paperargues that codified component knowledge is more easily spreadthan firm-specific architectural knowledge. Nevertheless, overtime, agglomerations may develop a cluster-specific form ofarchitectural knowledge that facilitates the rapid disseminationof knowledge throughout the cluster by increasing the learningcapacity of proximate firms and thereby conferring cluster-specificcompetitive advantages. 相似文献
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Gérard Poupeau François-Xavier Le Bourdonnec Tristan Carter Sarah Delerue M. Steven Shackley Jean-Alix Barrat Stéphan Dubernet Philippe Moretto Thomas Calligaro Marina Milić Katsuji Kobayashi 《Journal of archaeological science》2010
In this paper we evaluate the relative analytical capabilities of SEM-EDS, PIXE and EDXRF for characterizing archaeologically significant Anatolian obsidians on the basis of their elemental compositions. The study involves 54 geological samples from various sources, together with an archaeological case study involving 100 artifacts from Neolithic Çatalhöyük (central Anatolia). With each technique the artifacts formed two compositional groups that correlated with the East Göllü Da? and Nenezi Da? sources. The non-destructive capabilities of these methods are emphasized (albeit with certain analytical limitations in the case of SEM-EDS), suggesting important new techniques for Near Eastern obsidian provenance studies. 相似文献
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Andrew I. Duff Jeremy M. Moss Thomas C. Windes John Kantner M. Steven Shackley 《Journal of archaeological science》2012
X-ray fluorescence analysis of obsidian artifacts from sites located in Chaco Canyon and from three Chaco-era communities in New Mexico permits determination of their geological origin. These source data are used to describe patterning in obsidian procurement in sites located in Chaco Canyon dating from A.D. 500–1150, and in a three non-Canyon communities occupied during the period of Chaco Canyon's regional prominence (ca. A.D. 875–1150). These data demonstrate that the most proximate sources generally dominate the sourced obsidian assemblages from sites of all periods, but also suggest differences in procurement patterning both over time and across space. Within Chaco Canyon, there is a notable shift from Mount Taylor obsidian to use of Jemez Mountains sources over time. These data also suggest that earlier analyses of obsidian from sites in Chaco Canyon misidentified some obsidian artifact sources; these new data indicate the central areas of disagreement and provide a revision of procurement patterning. In the Chaco-era communities located outside Chaco Canyon, procurement patterning diverges. The Blue J community shows an increase in use of the nearby Mount Taylor source over time. Two communities located toward the southern extent of the Chaco great house distribution reveal a markedly distinct procurement pattern, obtaining nearly all of their obsidian from southern sources largely unrepresented at Chaco Canyon. Combined, these data provide new insights into raw material procurement and artifact production at sites in Chaco Canyon, and in communities occupied during the Chaco Phenomenon, the period of the Canyon's greatest regional influence. 相似文献
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