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1.
Discrete-choice theory and logit models are evaluated for their usefulness in analyzing migration patterns in a zonal system. The authors "argue that spatial effects and more specifically the relative location of zones are not taken into account in such analyses. We, therefore, introduce a measure of spatial structure and advocate its usage as a predictor of migration in such models. In an example of intrametropolitan migration in Toronto [Canada], we demonstrate that this variable is not only significant but also it improves the performance of all the other variables with the greatest impact on the distance between zones. In addition, inclusion of this variable improves the overall performance of the model in terms of residuals." 相似文献
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ABSTRACT In this paper we extend the contextual theory of demand to consider rational consumer behavior when the household must deal with some random fluctuation in the prices it faces. Prices at stores reflect “advertised specials,” which are potential cost reductions random across goods, and random in-store price changes, which can only be observed by visiting the store. Our theory of rational behavior includes: (1) calculation by the household of an ex ante plan for its planning period; (2) modification to take account of advertised specials; and (3) rational search behavior to take advantage of random fluctuations observable only on a given day. This theory utilizes an active cash balance as a buffer against random variations from planned daily expenditures, and reformulations of trip circuits to account for patterns of cost-minimizing search. 相似文献
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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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Mysticism and Dissent, Socioreligious Thought in Qajar Iran. By Mangol Bayat. Syracuse: Syracuse University Press, 1982. xvii + 228 pp.
Roots of Revolution. By Nikki Keddie. New Haven: Yale University Press, 1981. xii + 321 pp.
Islamic Values and Worldview: Khomeini on Man, the State and International Politics. By Farhang Rajaee. Lanham, MD: University Press of America, 1983. 148 pp. + notes. 相似文献
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Mobilizing for a New Life: “Canico” Settlement Rehabilitation in the Bairro of Maxaquene,Mozambique*
Barry Pinsky 《对极》1980,12(3):24-30
Located on the east coast of Africa, Mozambique won its independence from Portugal in 1975 following a protracted 10-year guerilla war led by FRELIMO—the Front for the Liberation of Mozambique. The experience of collective participation which was necessary for rural peasants to win the war against a much better equipped Portuguese army is now being carried over to all aspects of life including the rehabilitation of the shanty settlements which surround the larger cities and towns. In 1977 the newly created National Housing Directorate launched the first rehabilitation pilot project in part of the bairro of Maxaquene, in the capital, Maputo. After two years of intensive work, the original project area has quadrupled in size and an urban plan has been put in place encompassing 300 hectares and a population of 36,000. New water and electricity projects already serve 10,000 people. Infrastructure works and community facilities are being completed as rapidly as limited material and technical resources permit, and a self-help housing assistance program is underway. The rapid progress has only been possible because of the community's extraordinary efforts in putting into practice the philosophy of “counting on our own forces”. Hundreds of meetings of planning committees have been held and over 100 new block committees are active in the bairro. The people of Maxaquene are mobilized for a new life and they are succeeding in creating it. 相似文献
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B. N. Boots 《Geographical analysis》1977,9(4):379-387
The purpose of the paper is to determine if different generating processes produce cellular networks with distinctive contact number properties. Properties resulting from patterns produced by three generating processes, the Poisson, the compound negative binomial, and the “Smalley,” are examined in detail. The implications of the findings for the analysis of empirical cellular networks are discussed. 相似文献
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