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31.
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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ABSTRACT. Total cleared area in a von Thünen land-use model drives an atmosphere externality which depresses agricultural productivity uniformly throughout the region. Exogenous events that encourage clearance and use of a larger cultivated area (output price or population increase) exacerbate the externality. Imposition of a simple, corrective tax on land rents does not reverse these patterns but does mitigate the increase in the externality and leaves cultivators with higher incomes than they would obtain without the tax. We examine an optimal tax on land rents, designed to maximize the social value of land rents in the region, and an output tax.  相似文献   
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The chronology of the period is briefly considered in the light of the dendrochronological results which have appeared in recent years. Patterns of settlement history in different parts of the area are then examined, and it is suggested that in some of them the late fourth millennium was a period of population decline which was not reversed until the Early Bronze Age, 1000 years later. Detailed information about specific local occupation patterns is provided by recent work on the circum-Alpine lake villages. Changes in cultural patterns during the period, especially the appearance of the Corded Ware, are discussed and explanations of them reviewed. It is argued that changing patterns of gender relations were a major feature of the period, linked to processes which eventually led to the development of small-scale chiefdoms. The development of copper and bronze metallurgy and its connection to these processes are discussed.  相似文献   
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Book reviews     
P. L. Thomas (tr.). Hikayat Panglima Nikosa: The story of Panglima Nikosa, with an introduction and notes by R. H. W. Reece and P. L. Thomas. v, 45, 29 pp. Sarawak: Persatuan Kesusaster‐an Sarawak, [C1983].

Russell Jones (ed. and tr.). Hikayat Sultan Ibrahim: the short version of the Malay text. [v], 78 pp. Dordrecht: Foris Publications, 1983. (Koninklijk Instituut voor Taal‐, Land‐ en Volkenkunde. Bibliotheca Indonesica, 24.) Guilders 20.  相似文献   

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Book reviews     
Transmigration in Indonesia, by J M Hardjono. Oxford in Asia Current Affairs. Kuala Lumpur: Oxford University Press 1977; xv, 116 pp, 8 maps, 15 tables. £6.00.

Myths and Legends of Indonesia, by Jan Knappert. Singapore: Heinemann Educational Books (Asia) Ltd, 1977; 198pp. £2.40.  相似文献   

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Many timber finds lack some or all of the outer, sapwood rings formed in the years just before felling. In order to estimate felling date once the outermost remaining ring has been dated, it is necessary to estimate the number of sapwood rings originally present. Methods doing this for oak are reviewed in the light of an intensive study of living trees at one site and an extensive study of 175 samples from living trees in North Wales and northwest England. Some methods reported in the literature are found to be invalid. A method reported by Hollstein (1965) is most reliable, with modifications for known variations in sapwood number with position in the tree. At present the best available estimate is that a value of 30 sapwood rings be used (95% confidence limits: 19–50).  相似文献   
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