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Farmer adaptation to climatic variability is explored via an analysis of corn hybrid selection in southern Ontario. Corn hybrid varieties are available for a wide range of conditions, including accumulated heat, measured as Corn Heat Units (chus). Hybrids with higher chu ratings generally have higher yields, so long as there is sufficient heat for them to mature. Farmers choose their hybrid varieties prior to the growing season, in the face of uncertainty about the chus that will accumulate at their location. Farmers in the sample counties showed a consistent tendency to adjust their hybrid selection on the basis of the previous year's growing conditions. After the high chu year of 1991, farmers chose significantly more longer-maturing and potentially higher-yielding, but riskier varieties. After the lower chu years of 1992 and 1993, farmers' hybrid selections became markedly more conservative. L'étude de I'adaptation des fermiers aux changements climatiques se fait par une analyse de /'hybridation du maïs au sud de l'Ontario. Les variétés de maïs hybrides conviennent à différentes conditions climatiques in-cluant la chaleur accumulée, mesurée en Unitées de Chaleur de Maïs (ucms). Les hybrides ayant une valeur ucm plus élevée donnent généralement un rendement plus élevéà condition qu'ils bénéficient d'assez de chaleur pour mûrir. Les fermiers des comtés sélectionnés ont démontré une tendance persistante à baser leurs sélections d'hybrides en fonction des conditions de crois-sance de I'année précédente. Depuis 1991, année ayant connu un taux élevé d'UCM, les fermiers ont opté pour un type d'hybride à croissance prolongée, au potentiel de rendement plus élevé mats également plus risqué. Les années 1992 et 1993 ayant connu un niveau ucm moins élevé, les fermiers ont alors sélectionné des hybrides plus traditionnels.  相似文献   
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The sophistication of regional economic models has been demonstrated in numerous ways, most recently in the form of linking several modeling systems or in the expansion in the number of equations that can be manipulated successfully to produce impact analyses or forecasts. In this paper, an alternative perspective is employed. What do regional macro-level forecasts indicate about the process of structural change? A new methodology is illustrated that enables analysts to make forecasts of detailed structural change in the interindustry relations in an economy. Using a regional econometric input-output model developed for the Chicago metropolitan region, derived input-output tables are extracted for the period 1975–2016. These tables are then analyzed to determine the forecasted direction of structural changes for the region. The innovation illustrated here is based on a model that exploits the general equilibrium spirit of computable general equilibrium models through the adjustment of input coefficients to clear markets.  相似文献   
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This paper summarizes results of a research project funded by the Overseas Development Administration of the UK Government. Its aims were to explore the nature and extent of foreign direct investment in Poland, and to assess the extent of integration of such investment with the indigenous economy. The research involved interviews with Polish government ministries, banks, development agencies, inward investors and indigenous firms. It concludes that there are numerous financial and technical obstacles to indigenous business development. The majority of inward investors aim to serve the Polish and other Central and Eastern European markets rather than simply selling cheaply produced products to the West. Moreover, most have already developed significant local sourcing from Polish suppliers.  相似文献   
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ABSTRACT. This paper proposes a new method for estimating a monthly regional production model. The technique involves treating the region's monthly industrial output as a latent variable, which is in turn a function of capital (prosed by energy usage) and labor inputs. Annual observations on regional value added correspond to the summation of the unobservable monthly series over the 12 months, while changes in the national Industrial Production index help infer the series' month-to-month fluctuations. The model is estimated using the Kalman filter and the method of maximum likelihood. The estimates are used to compute monthly indices of regional value added for 15 individual 2-digit industries, and for the aggregate manufacturing sector in the Seventh Federal Reserve District. In a comparison of out-of-sample forecasting accuracy, the mixed-frequency model outperforms both the traditional parametric Cobb-Douglas and nonparametric Atlanta methods over the 1988–89 forecasting horizon.  相似文献   
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ABSTRACT. The paper applies an inventory model to the standard Weber-Moses location-production problem. By setting the problem within a time framework, costs are seen to be incurred by both the holding of goods and the shipment of goods. The optimum location of the firm is seen to depend not only on transportation costs and the nature of the firm's production function, but also on the value of the materials being shipped. Under these conditions there is no homogeneous solution to the Weber-Moses problem. Furthermore, it is shown that the value added at the point of production is the primary factor which governs the optimum location of the firm.  相似文献   
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Book reviews     
Adam Watson, Diplomacy: the dialogue between states. Eyre Methuen, London, 1982, pp.239. $28.95.

Desmond Ball and J.O. Langtry (eds). Civil Defence and Australia's Security in the Nuclear Age. Strategic and Defence Studies Centre, Australian National University, Canberra, and George Allen and Unwin Australia, Sydney. 1983, pp. 359. $12.95.

Bruce Grant, Gods and Politicians. Allen Lane, Ringwood, Victoria, 1982, pp.wi + 190. $16.95.

B.A. Santamaria, Santamaria, Against the Tide. Oxford University Press, Melbourne, 1981, pp. 382. $22.50

M.M. Kritz. C.B. Keely and S.M. Tomasi (eds.), Global Trends in Migration: Theory and Research on International Population Movements. The Centre for Migration Studies, New York, 1981, pp.xi + 433. $US14.95 (cloth), $US9.95 (paper).

Robert Cassen, Richard Jolly, John Sewell and Robert Wood (eds). Rich Country Interests and Third World Development. Croom Helm, London and Canberra, 1982, pp. 369. $27.75.

David Childs, The GDR: Moscow's German Ally. George Allen and Unwin, London, 1983, pp. xiii + 346. $49.95 (cloth), $19.95 (paper).

Alexander Shtromas, Political Change and Social Development; The Case of the Soviet Union. Verlag Peter Lang, Bern, 1981, pp 173. S Fr 40.

Joel K. Goldstein, The Modern American Vice Presidency. The Transformation of a Political Institution. Princeton University Press, Princeton, N.J., 1982, pp. xxii + 409. $US36.50 (cloth) $US 10.50 (paper).

Colin Mackerras, Modern China ‐ A Chronology from 1842 to the Present. Thames and Hudson, London, 1982, pp. 703. $60.00

John H. Fincher, Chinese Democracy: The Self Government Movement in Local. Provincial and National Politics, 1905–1914. Australian National University Press, Canberra, 1981, pp. 27s6. $23.95.

A.J. Youngson, Hong Kong: Economic Growth and Policy. Oxford University Press, Hong Kong, 1982, pp. 163. $10.95.

Peter Wesley‐Smith, Unequal Treaty 1898–1997: China. Great Britain and Hong Kong's New Territories. Oxford University Press, Hong Kong. 1980, pp. XV + 270. $39.00.

Michael Leifer, Indonesia's Foreign Policy. George Allen & Unwin, London, 1983, pp. xvii + 198. $39.95.

Grant Evans, The Yellow Rainmakers. New Left Books/Verso, London, 1983, pp. 202. $33.50 (cloth) $10.50 (paper).

Stewart Firth, New Guinea Under the Germans. Melbourne University Press, Melbourne, 1982, pp. xiii + 216. $25.00.

R.J. May (ed.), Micronationalist Movements in Papua New Guinea. Political and Social Change Monograph No. 1, Department of Political and Social Change, Research School of Pacific Studies, Australian National University, Canberra, 1982, pp. xi. + 486 $9.50.

Politics in Melanesia. Institute of Pacific Studies, University of the South Pacific, Suva, 1982, pp. xxi + 170. $4.00

Foreign Forces in Pacific Politics. Institute of Pacific Studies, University of the South Pacific, Suva, 1983, pp. xv + 325, $6.00.

Mike Moore, A Pacific Parliament. Asia Pacific Books, Wellington and the Institute of Pacific Studies, University of the South Pacific, Suva, 1982, pp. 86. No price given.

Australia and the South Pacific. Conference Papers and Reports. Centre for Continuing Education, Australian National University, Canberra, 1983, pp. 157. $8.00.

Alan R. Taylor, The Arab Balance of Power, Syracuse University Press, Syracuse, 1982, pp. xii + 165. $US22.00 (cloth) $US11.95 (paper).

Tareq Y. Ismael, Iraq and Iran: Roots of Conflict. Syracuse University Pess. Syracuse. 1982, pp xii + 226. $US24.00 (cloth) $US12.95 (paper).

Peter Gubser, Jordan: Crossroads of Middle Eastern Events. Croom Helm, London and Westview Press, Boulder, Colorado, 1983, pp. xi+ 139. £13.50.

Ibrahim Ibrahim (ed.), Arab Resources: The Transformation of a Society. Croom Helm, London, 1983, pp. 304. $24.25.

David Goldsworthy, The International Politics of the Namibian Dispute, Discussion Paper No. 3, 1982, pp. 41

Jock McCulloch, South Africa's Invasion of Angola: Many Reasons Why. Current Issues Brief No. 7, 1981, pp. 10 both published by the Legislative Research Service, Department of the Parliamentary Library, Canberra.  相似文献   

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