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ABSTRACT. This paper uses new estimates of metropolitan factor demand and output supply functions to study how federal, state, and local fiscal policies affect metropolitan economies. We illustrate our work with findings for ten metropolitan areas in five states for changes in state corporate income taxes, local property taxes, the federal corporate income tax, an investment tax credit, interest rates, public capital stocks, output prices, and tax and regulatory policies affecting gross wages. It is clear from these simulations that a policy that is nominally the same everywhere will have repercussions that vary widely across regions and cities.  相似文献   
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The recent application by Burton and Krinsley (1987) of back-scattered electron (BSE) petrography to obsidians from sources located in the south-western United States established that this method can effectively resolve and characterize included micro-crystalline phases that have proven difficult to analyse by optical thin-section microscopy. In the first extension of their original study, we have examined, using BSE petrography, obsidians from island sources located in the Mediterranean, including sources known to have been exploited in prehistory. Because of the kinetic contrasts on their crystallization, these microcrystalline phases reflect the magmatic history of the obsidian, providing information about superheating, supercooling, sub-solidus processes, and other phenomena. This information is of significance for the chemical analysis of Mediterranean obsidians and also as the basis for a powerful alternative to existing non-destructive analytical methods for the sourcing of archaeological and art-historical obsidian.  相似文献   
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Classifying coins found during excavation is a challenging task for the archaeologist. This paper describes a multimedia system designed to assist the archaeologist by enabling him either to classify coins based on a pre-existing catalogue or to draw up his own catalogue for specific purposes. The system can also be used to train novices in the field: following an initial screening, the archaeologist only has to examine coins specifically requiring his expertise. A case study uses coins minted in Salerno 800–1200 AD, but the system has been designed to classify any set of coins by simply changing the underlying knowledge base. Very little training is required to operate the user-friendly system, which runs on multimedia PCs, as it is written using the C++ language and makes full use of the advanced features of Windows 3.11.  相似文献   
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Ancient mortars from northern Italy, dating from the fifth to the seventeenth century AD, were examined in order to formulate an hypothesis regarding the origin of the white lumps often observed in these mortars and in other samples of the same geographical provenance. Various characterization techniques were employed, including scanning electron microscopy, X-ray powder diffraction and Fourier transform infrared (FTIR) and micro-FTIR spectroscopy.  相似文献   
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The present paper surveys the discussions conducted by official statisticians regarding the ideal structure according to which a national data collection system should have been designed if it was to meet the challenges put up by the various transformation Western countries have undergone since the beginning of the 19th century. Arguments in favour of coordination, centralization, or decentralization have emerged for the first time in 1832 Britain, when the Statistical Bureau of the Board of Trade was created. Up to 1945, this debate went on, the industrial take-off, the economic crises, and the world wars all being occasions for its protagonists to put forward their preferred view. The perspective we take here is original in two respects: on the one hand, instead of confining ourselves to the major statistical systems (those of France, Britain, and the USA), we intend to evoke a large number of cases and, from this comparative standpoint, propose a general account of the drive towards centralization; on the other hand, instead of restraining our-selves to the 19th century, we cover the entire time-frame extending from 1800 to 1945.  相似文献   
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