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91.
ABSTRACT. Traditional models of regional diversification do not capture the trade-off between stability and living standards. In this paper, we characterize regions as open activity models subjected to both productivity and price shocks. We then partially rank small diversification policies by the direction in which they point away from the current industrial structure in mean-variance space. Some general patterns emerge. In particular, diversification for regional self-sufficiency and away from regional comparative advantage may be undesirable. 相似文献
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Evans AW 《Journal of regional science》1990,30(4):515-531
"This paper questions the plausibility of the assumption of interregional equilibrium in recent research into migration and the valuation of amenities in the United States. It is shown that it is difficult to develop a satisfactory explanation for continuing net migration which is compatible with the equilibrium assumption, and that recent relevant research generally fails to support the idea that the U.S. economy is in equilibrium. The association of higher rent levels with in-migration is explained as a short-run phenomenon. If the spatial economy is in disequilibrium, then the valuations of amenities assuming equilibrium will be biased, being probably too low in areas of net in-migration and too high in areas of net out-migration." 相似文献
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Archaeometric analysis of ceramic production in Tiwanaku state (c.500–1000 ce): An exploratory study
J. P. Ogalde A. Korpisaari C. Riera‐Soto B. Arriaza C. Paipa P. Leyton M. Campos‐Vallette N. Lara J. Chacama 《Archaeometry》2021,63(1):53-67
The chemical and mineralogical characterization of seven ceramic fragments produced within Tiwanaku state (c.500–1000 ce ) is reported. The instrumental techniques used included X‐ray elemental and mineralogical chemical analysis, Raman spectroscopy, and scanning and light microscopy. The results indicate there are several clay types, although they show similarities, such as the use of a plant‐based temper. The red colour of the decoration is hematite, and manganese oxides such as jacobsite are present in the black. The white colour is a mixture of gypsum and clay, and the orange is a mixture of hematite and clay. The use of colours, the quality of the clays and the temperatures reached during pottery firing point to expertise in ceramic production and to complex decision‐making processes. The multi‐elemental archaeometric approach documented here could become an important tool to shed a light on ancient ceramic technology and the internal variance of Tiwanaku pottery. 相似文献
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García-Heras Manuel Agua Fernando Madiquida Hilario Fernández Víctor M. de Torres Jorge Villegas María-Ángeles Ruiz-Gálvez Marisa 《African Archaeological Review》2021,38(2):297-318
African Archaeological Review - A set of beads made of glass, gastropod mollusk shell, and fishbone from a Swahili occupation level on Ibo Island (northern Mozambique) is dated to the eleventh and... 相似文献