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The dynamics of biomass growth implies that the yield of irrigated crops depends, in addition to the total amount of water applied, on irrigation scheduling during the growing period. Advanced irrigation technologies relax constraints on irrigation rates and timing, allowing us to better adjust irrigation scheduling to the varying needs of the plants along the growing period. Irrigation production functions, then, should include capital (or expenditures on irrigation equipment) in addition to aggregate water. We derive such functions and study their water-capital substitution properties. Implications for water demand and adoption of irrigation technologies are investigated. A numerical example illustrates these properties. 相似文献
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Measuring the recreational value of agricultural landscape 总被引:11,自引:0,他引:11
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We study optimal adaptation to climate change when the harmful consequences of global warming are associated with uncertain occurrence of abrupt changes. The adaptation policy entails the accumulation of a particular sort of capital that will eliminate or reduce the catastrophic damage of an abrupt climate change when (and if) it occurs. The occurrence date is uncertain. The policy problem involves balancing the tradeoffs between the (certain) investment cost prior to occurrence and the benefit (in reduced damage) that will be realized after the (uncertain) occurrence date. For stationary economies the optimal adaptation capital converges monotonically to a steady state. In most cases, investment begins immediately. However, if the initial adaptation capital exceeds a pre-specified threshold level, which lies above the optimal steady state, investment is delayed while the capital stock decreases (due to depreciation) and commences only when it reaches this threshold level. For growing economies the optimal adaptation capital stock approaches the maximal economic level above which further accumulation is ineffective. 相似文献
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We develop aggregate measures of the recreational value of types of open space when data on individual site visitation are not available. Our procedure accounts for both the allocation (between the different types of open space) and participation (total number of trips) decisions. The procedure is applied to estimate the recreational value of three types of open spaces (beaches, urban parks and national parks) in Israel. 相似文献
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The endogeneity of the efficient frontier in the mean-variance model of portfolio selection is commonly obscured in the portfolio selection literature and in widely used textbooks. The authors demonstrate this endogeneity and discuss the impact of parameter changes on the mean-variance efficient frontier and on the beta coefficients of individual assets. 相似文献
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Research on immigration and real estate has found that immigrants lower house prices in immigrant destination neighborhoods. In this article, we find that this latter result is not globally true. Rather, we show that immigrants can raise neighborhood house prices, at least in the case of the wealthy immigrants that we study. We exploit a surprise suspension and subsequent closure of a popular investor immigration program in Canada to use a difference‐in‐differences methodology comparing wealthy immigrant destination census tracts to nondestination tracts. We find that the unexpected suspension of the program had a negative impact on house prices of 1.7–2.6% in the neighborhoods and market segments most favored by the investor immigrants. This leads to an approximate lower bound on the effect of capital inflows of 5%. 相似文献
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This paper describes the relationship between land use regulation and residential construction. We characterize regulations as either adding explicit costs, uncertainty, or delays to the development process. The theoretical framework suggests that the effects on new construction vary by the type of regulation. Using quarterly data from a panel of 44 U.S. metropolitan areas between 1985 and 1996, we find that land use regulation lowers the level of the steady-state of new construction. Our estimates suggest that metropolitan areas with more extensive regulation can have up to 45 percent fewer starts and price elasticities that are more than 20 percent lower than those in less-regulated markets. One implication of regulations that lengthen the development process is that the short- and long-run effects of demand shocks will vary relative to conditions in markets without such delays. We find support for this observation in the data. As well, we find other differences by type of regulation: development or impact fees have relatively little impact on new construction, but regulations that lengthen the development process or otherwise constrain new development have larger and more significant effects. 相似文献