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Beef cattle producers were surveyed in Texas and Nebraska to investigate perceptions of sources of risk, the effectiveness of risk management strategies, and interest in further risk management education, particularly production risk, using probit analysis. Important decision variables identified are age, prior use of risk management tools, previous attendances of risk management education, and risk aversion. Severe drought and cattle price variability are identified as primary risk factors with potential to affect farm income. Extremely cold weather and disease are of less importance. Understocking pasture and storing hay are perceived most effective as risk management options.  相似文献   
53.
The nutrition transition in diets and health is closely tied to other aspects of economic development, including agricultural transformation and urbanization as well as demographic change and epidemiological transition from infectious to noncommunicable disease. Over time, dietary patterns typically shift from widespread inadequacy of many foods and nutrients, especially for children and mothers, into surplus energy intake and rising obesity with continued inadequacy of healthier foods. Diet‐related diseases remain the largest single cause of premature death and disability in all regions. This article combines food availability and dietary intake data from more than 100 countries over 30 years with a wide range of other evidence to characterize the nutrition transition and its association with changes in agricultural production and the food environment, asking how future dietary patterns might be steered toward healthier outcomes as national incomes grow.  相似文献   
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This paper examines the trade, FDI, and welfare impacts of (liberalizing) 9/11 security measures at the Canada–US border. First, the study provides econometric estimates of the impact of post 9/11 security measures on bilateral (US–Canada) trade flows. Second, we compute sectoral tariff rates “equivalent” to the 9/11 security measures using these econometric estimates together with a three-region nine-sector general equilibrium model. Finally, we assess for both the Canadian and the US economies: 1) the (general equilibrium) impacts on trade, FDI, and welfare, of (liberalising) the 9/11 US security measures and 2) the economic impacts of a change of security paradigm toward a North American Security Perimeter within a Customs Union that would liberalize the Canadian and US 9/11 security measures at the Canada–US border and shift them at the external security perimeter.  相似文献   
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Agriculture's importance in the process of economic growth highlights the role of sustained advances in farm production practices by improving the quantity and quality of farm products. In this context, investment in improved agricultural technology continues to be an important avenue of assistance to the developing countries. However, the increased resource pressures facing both aid donors and recipients have emphasised the need for the prior assessment of the potential benefits of aid projects to assist effective aid planning and management. Here, the main requirements are to establish viable project goals for translation into effective programmes, to predict the likely project impacts, and to evaluate the potential benefits and costs of adopting the project's outcomes. An ex ante assessment of assistance in controlling a major livestock disease in Indonesia's eastern islands is described in this paper. The annual net benefits from controlling this disease ranged between $A0.45 and $A2.5 million according to the mortality rate reduction achieved. The benefits were shared between beef producers and consumers according to the market elasticity conditions assumed.  相似文献   
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Structural modeling has been under study in recent years as a method for dealing with complex societal problems, and is growing in acceptance as a tool for understanding complex social phenomena. Structural models demonstrate the interactions of the separate elements of a system and their combined overall effect. Thus, the nature of the problem for which this method of analysis is appropriate is different from complex problems of the traditional disciplines which lend themselves to reductionist approaches. This is because complex policy problems of society cannot be “solved” with precise analysis. Kenneth Boulding suggests that there are two ways to cope with a complex policy problem, either to “slice” the problem into partial equilibrium sections or “squeeze” it by aggregating numerous variables into a single index or macho variable. Structural modeling is an approach which comes under the general strategy of squeezing the problem and is promising because of the ability to include a range of macro variables which provide insights about social change. The articles in this issue treat several interesting aspects of this approach. In this article we wish to recall for consideration a central purpose for developing such methods. We have taken a historical approach to indicate some of the roots of the concern for the effect of technological process on social change. Within this context, we discuss the nature of the contributions made by the articles in this issue and what promise the methods offer to addressing the historical concern.  相似文献   
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The necessity of entering a sequence of interrelated state primaries has forced presidential candidates to be much more deliberate in planning campaign finances. This paper presents a linear programming model for optimal allocation of time and money to each primary in order to maximize the number of delegates won. The model attempts to quantify and exploit the relationships between performance in early primaries and performance in later primaries, which has heretofore been labeled the “snowball effect.” Finally, the model, whose major use would be in overall strategic planning, is illustrated with an example.  相似文献   
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