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141.
Given the importance of Chinese foodgrain production both in China and in the world food market, it is useful to explore the sources of the increased variabilities of China's foodgrain production (Stone and Zhong, 1989). A production function with composite error structure and a heteroscedastic disturbance is applied to cross-section and time-series data from China. The function provides information on the contributions of inputs to production variance and therefore on risk. It is found that production variance is positively related to sown area, chemical fertiliser and irrigation, and is negatively related to electricity use. However, most of the estimates determining the marginal risk effects lack statistical significance. This suggests that the measured controllable factors do not contribute very significantly to Chinese foodgrain production variability.  相似文献   
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Fear has been widely expressed that the modern rice varieties have created large disparities in regional income distribution, as the productivity gap between favorable and unfavorable rice-production environments widened due to differential technology adoption throughout South and Southeast Asia over the last two decades. Technology affects the income of farm population directly through its effects on productivity and factor use, and indirectly through its effect on factor prices. In particular, the ultimate distributional impact of modern varieties will critically depend on the interregional labor-market adjustments through migration in response to regional wage differentials created by the differential technology adoption, since labor is the main resource of the majority of the rural population. We studied favorable and unfavorable rice-growing villages in the Philippines, and found that adoption of modern varieties during the 1970s was positively related to population growth rate. Contrary to popular belief, no association was observed between wage rates and adoption of modern varieties as of 1986. These findings support the hypothesis that the differential adoption of modern rice varieties induced interregional labor migration toward equalization of wage income across different production environments.  相似文献   
144.
The World Bank's commodity price projections are widely used for various planning purposes. Two aspects of the Bank's projections of relative prices are studied in this paper. The first is whether the forecasts make efficient use of the information available at the time the forecast is made. The second is whether the forecasts predict future prices with greater accuracy than alternative forecasting methods. These matters are studied by comparing the World Bank's past price projections with the actual prices that were subsequently observed. The results show that, overall, the World Bank forecasts do not pass either test. First, the World Bank forecasts are informationally inefficient. Prediction error (projection minus actual price) tends to be positively correlated with the projections themselves. Although the direction of future price movements tends to be correctly predicted, the magnitude of these movements tends to be overpredicted. Second, the World Bank forecasts do not perform well even compared with the simplest of alternative forecasting methods - the prediction of no change.  相似文献   
145.
The degree of spatial market integration in European Community agricultural product markets is investigated. The methodology is based on co-integration analysis. A two-step testing procedure is applied to test the existence of the ‘Law of One Price’ which should be in force if these markets are truly integrated. The results show that market integration has not been achieved in a number of cases even when MCAs are subtracted from the price series used.  相似文献   
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Trends in agricultural trade for South and Central America are documented and the reform process is discussed. Performance of the agricultural sector of the region is evaluated. Challenges for policy makers are reviewed, ranging from macroeconomic policy to science and technology.  相似文献   
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Structural changes in U.S. agriculture, influenced by technological and institutional forces, have altered the economic and social characteristics of rural America, especially that segment of rural America populated by farmers and their families. Changes in the structure of agriculture have greater implications for small scale farmers, many of whom are African American, in that strategic options for their farm-firms are constrained to: increasing their farm size, exiting farming, and obtaining off-farm employment to survive. This article presents a rationale for public support of limited resource farmers, identifies structural trends in U.S. agriculture and their impacts on African American farmers, discusses economic problems unique to these farmers, and recommends needs for specific public policies and development programs.  相似文献   
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