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101.
Vector autoregression (VAR) methods are used to analyse the contribution of supply, demand and policy shocks to unpredictable fluctuations in the market for Australian wool. VAR procedures are compared with conventional structural econometric models as methods for decomposing sources of instability. While each has advantages and disadvantages, VAR procedures might be viewed as preferable when the underlying market structure is complex and uncertain, as it is in the case of wool. Based on the results obtained, demand shocks are the dominant source of uncertainty in the wool market in the absence of Australian Wool Corporation intervention, but intervention has blunted their effects, reducing market uncertainty and increasing the average level of prices and revenues.  相似文献   
102.
Regional Economic Impacts of Fusarium Head Blight in Wheat and Barley   总被引:2,自引:0,他引:2  
Fusarium Head Blight is a fungus affecting wheat and barley in the upper Midwest region of the United States. The purpose of this study is to estimate the direct and secondary regional economic impacts of Fusarium Head Blight infestations from 1998 to 2000. Cumulative direct production and price impacts from Fusarium Head Blight in hard red spring, soft red winter, durum wheat, and barley are estimated at $871 million over the period, with secondary economic losses of $1.8 billion. The total impacts of $2.7 billion were concentrated in North Dakota and Minnesota, which accounted for 55% of total losses over the period.  相似文献   
103.
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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Undergraduate Coursework in Economics: A Survey Perspective   总被引:1,自引:0,他引:1  
Survey results from a large sample of economics departments describe offerings for principles courses, coursework requirements for economics majors, and program augmentations such as capstone courses, senior seminars, and honors programs. Findings are reported for all institutions, and institutions are subdivided into six different categories based on public or private control and the highest economics degree offered. The coursework required for the economics major typically consists of ten courses, five in a required core and five electives. The most conspicuous curriculum change over the past 30 years is the rise of econometrics as a required course, now mandatory at about half of major programs. The authors estimate that about 40 percent of students who matriculate as first-year undergraduates take at least one economics course before they leave.  相似文献   
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108.
The major countries of the former Soviet Union—specifically Russia, Ukraine, and Kazakhstan—are becoming increasingly important in world agricultural markets. The two main developments are that this region has become a large grain exporter, especially of wheat and barley, and Russia a big agricultural importer, especially of meat. These trends should continue for the next decade. However, policies to expand the livestock sector could mitigate these developments, as increased domestic meat production would reduce both meat imports and surplus feed grain for export. Also, further growth in the region's grain exports will require improvement in the infrastructure for storing and transporting grain.  相似文献   
109.
This study uses panel data to demonstrate two dimensions of land ownership: the distribution between households at a given time and changes within a household over time. We note that recognizing the latter dimension is only possible when analyzing rare long‐term panel data. We estimate a model for land ownership using a version of the correlated random effects estimator to uniquely identify the determinants of both dimensions amongst Kenyan smallholders. We find life cycle effects are a key determinant of both distributions, and identify important ways in which initial conditions such as inheritance and off‐farm income relate to the dynamics of ownership. We find that population density is a key determinant of differences between households, but also that a given household's land ownership is not affected in the short term as population density increases around them. Controlling for population density, households own more land when they are closer to road networks where the economic value of land is higher. We find important vulnerabilities for the land security of widows, but this vulnerability is geographically heterogeneous.  相似文献   
110.
Replacement brood cows are among the most significant investments for cow-calf operations, thus crucial to profitability. Many cow-calf producers find it cost effective to purchase replacements from a reliable replacement heifer seller, though by doing so they increase risk of reproductive inefficiency due to unknown characteristics of the heifers. When important information about a product is missing to buyers, a seller can build a reputation over time that acts as signal for quality. Previous work has explored reputation effects in feeder cattle markets, but to our knowledge we are the first to explore reputation effects in bred replacement cattle markets. Using data from an annual replacement heifer sale, we analyze the values of heifer characteristics and test for premiums from reputation development. After controlling for reproductive practices, breed, and other characteristics, we find reputation does not play the role that Shapiro theorized. In this sale, the lot order is strategically chosen and may indicate bred heifer quality to buyers, replacing the need for reputation as a signal. This study highlights the importance of quality signals and regional preferences in bred replacement cattle marketing and lays the empirical groundwork for future studies to test Shapiro's theory.  相似文献   
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