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991.
The rapid urbanization in developing countries implies an increasing pressure on urban agriculture for production. As most perishable food products come from this agriculture in close proximity to population concentrations, we analysed from an agronomic point of view how market-garden farmers can meet this increasing urban demand. This work took place in the case of Mahajanga, a secondary city with high increasing demographic rate on the Northwest coast of Madagascar. Based on preliminary surveys to characterize the farming systems (on a sample of 91 farms), 11 market-garden farmers chosen in the three main agricultural zones of the urban area were surveyed during two years. Surveys aimed at understanding their decision rules in crop choices, crop allocation to land and resource management, and to estimate their room for manoeuvre to increase their leafy vegetable areas under cultivation. The wholesalers and retailers who buy the farmers’ produce were also surveyed. A previous model of decision rules regarding crop location on farm territory was used to analyse the on-farm surveys and cartographic methods (GIS and on-farm manual representations) were used to quantify the land use. We highlight the following major points. (1) The leafy vegetable production in the surveyed farms already intensively uses land: farmers have complex decision rules largely depending on the water dynamics in the two main environments (lowlands and lakesides) where leafy vegetables are cultivated during the dry season. (2) The scarcity of farmers’ resources (labour money and water) leads to very little internal room for manoeuvre to increase the leafy vegetable production in the farms. (3) At territorial level however, some land reserve exist in one of the lowlands, but not on lakesides. The water availability for agriculture must be better informed through specialized hydrologic studies, as one of the main constraints nowadays to extend the agricultural area. An extrapolation to other cases of urban agriculture is then discussed as well as the role of agronomy to help urban planners to consider the place of agriculture in the urban development. 相似文献
992.
This article uses information on out‐of‐pocket housing cost and house price appreciation along with the geo‐coded version of the Panel Study of Income Dynamics to consider the differences in the impact of these and other variables on the tenure choices of sample households across three time periods, the 1970s, the 1980s and the 1990s. Specifically, an extended continuous time probability model is used to examine households' transitions from renting to owning and subsequent possible transitions either back to rental tenure or to another owned home during our three observation periods. Coefficient estimates show that financial variables such as house price appreciation and out‐of‐pocket housing cost play an important role in determining all the transitions. In addition, the analysis demonstrates the interesting result that the cumulative likelihoods of homeownership derived from the model are consistently lower than the probabilities of an initial transition to homeownership from rental tenure during the observation period. Finally, the magnitude and timing of the impact on homeownership of a policy experiment that eliminates the mortgage interest deduction are shown to differ substantially across the three decades. 相似文献
993.
994.
Accurate estimation of the equity premium (the expected difference between the returns to a well-diversified stock market portfolio and a riskfree asset) is of central importance in many applications of finance theory including project appraisal and portfolio selection. The standard approach is to take the average observed excess returns to the market over some recent time period (sometimes referred to as the ex post equity premium) and apply this as an unbiased estimate of the ex ante equity premium. The paper reviews the problems associated with such an approach and contrasts it with alternative theoretical techniques. 相似文献
995.
Intermediate macroeconomics textbooks introduce financial markets into the IS-LM analysis but typically as a beginning-of-period consideration. Here the financial market is introduced in an end-of-period model. 相似文献
996.
W. W. Chan L. M. Mak Y. M. Chen Y. H. Wang H. R. Xie G. Q. Hou 《Journal of Sustainable Tourism》2013,21(5):563-574
This paper investigates solar control film as an energy saver in the fast growing hotel sector in southern China. It investigates claims made for this low-cost retrofitted material in hotel rooms, calibrating reductions in solar gain in summer. It provides reliable and independent data about the performance and economic viability of solar control film in real hotel environments. The study found that, by limiting solar gain, the film helps limit tourism's impact on global warming and climate change. The paper also foreshadows new technical glazing developments. 相似文献
997.
In this paper we consider a risk process in which claim inter-arrival times have a phase-type(2) distribution, a distribution with a density satisfying a second order linear differential equation. We consider some ruin related problems. In particular, we consider the compound geometric representation of the infinite time survival probability, as well as the (defective) distributions of the surplus immediately prior to ruin and of the deficit at ruin. We also consider explicit solutions for the infinite time ruin probability in the case where the individual claim amount distribution is phase-type. 相似文献
998.
999.
Recent findings in research on context effects indicate that, as opposed to choices under hypothetical settings, compromise effects are significantly attenuated in binding settings that include real payments for products. The present investigation examines to what extent this finding applies to yet another context effect, namely the similarity effect (SE). The SE stipulates that, compared with initial shares of two options A and B in a binary choice set, the introduction of an option C that is dissimilar to B but similar to A will hurt the latter more than the nonadjacent option B. The conducted online survey examines the SE in unforced choices of experienced consumers between real brands across three consumer good categories. The results confirm that the SE is evidently reduced under real payment conditions, hence confirming the hypothesis that the applied choice setting moderates the efficacy of the composition of choice sets. 相似文献
1000.