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ABSTRACT. Nearly all regional input-output models have been constructed without a proper accounting of inflows and outflows of personal income and personal consumption expenditures. Typically invoked is a no cross-payments assumption, analogous to the no cross-hauling assumption for commodities. We present a new accounting framework based on the classification of flows according to the location of income generation, receipt, and spending, and argue that only flows endogenous in all three respects should be part of a closed regional I-O model. We use the framework to compute the upward bias in multipliers in a typical regional I-O model. We also present several methods for estimating transboundary flows. 相似文献
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Journal of World Prehistory - This paper analyses and re-evaluates current explanations and interpretations of the origins, development and societal context of metallurgy in the Balkans (c.... 相似文献
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ABSTRACT. Average monthly price data from twelve hinterland markets and the Houston port price for wheat are studied in a cointegration framework using the Engle-Granger "two-step" procedure and Johansen's maximum likelihood procedure. Out-of-sample forecasts from an error correction model are compared to those from a vector autoregression fit to levels and a univariate autoregression fit to first differences. This comparison suggests that modeling these (cointegrated) data as a levels vector autoregression, rather than as an error-correction process, results in significantly higher error bias, but lower error variance, at long horizons. 相似文献
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Frank Winchell Michael Brass Andrea Manzo Alemseged Beldados Valentina Perna Charlene Murphy Chris Stevens Dorian Q. Fuller 《African Archaeological Review》2018,35(4):483-505
Four decades have passed since Harlan and Stemler (1976) proposed the eastern Sahelian zone as the most likely center of Sorghum bicolor domestication. Recently, new data on seed impressions on Butana Group pottery, from the fourth millennium BC in the southern Atbai region of the far eastern Sahelian Belt in Africa, show evidence for cultivation activities of sorghum displaying some domestication traits. Pennisetum glaucum may have been undergoing domestication shortly thereafter in the western Sahel, as finds of fully domesticated pearl millet are present in southeastern Mali by the second half of the third millennium BC, and present in eastern Sudan by the early second millennium BC. The dispersal of the latter to India took less than 1000 years according to present data. Here, we review the middle Holocene Sudanese archaeological data for the first time, to situate the origins and spread of these two native summer rainfall cereals in what is proposed to be their eastern Sahelian Sudan gateway to the Red Sea and the Indian Ocean trade. 相似文献