Agricultural input and output status in southern Xinjiang,China is introduced,such as lack of agricultural input,low level of agricultural modernization,excessive fertilizer use,serious damage of environment,shortage ...Agricultural input and output status in southern Xinjiang,China is introduced,such as lack of agricultural input,low level of agricultural modernization,excessive fertilizer use,serious damage of environment,shortage of water resources,tremendous pressure on ecological balance,insignificant economic and social benefits of agricultural production in southern Xinjiang,agriculture remaining a weak industry,agricultural economy as the economic subject of southern Xinjiang,and backward economic development of southern Xinjiang.Taking the Aksu area as an example,according to the input and output data in the years 2002-2007,input-output model about regional agriculture of the southern Xinjiang is established by principal component analysis.DPS software is used in the process of solving the model.Then,Eviews software is adopted to revise and test the model in order to analyze and evaluate the economic significance of the results obtained,and to make additional explanations of the relevant model.Since the agricultural economic output is seriously restricted in southern Xinjiang at present,the following countermeasures are put forward,such as adjusting the structure of agricultural land,improving the utilization ratio of land,increasing agricultural input,realizing agricultural modernization,rationally utilizing water resources,maintaining eco-environmental balance,enhancing the awareness of agricultural insurance,minimizing the risk and loss,taking the road of industrialization of characteristic agricultural products,and realizing the transfer of surplus labor force.展开更多
A large number of mathematical models were developed for supporting agricultural production structure optimization decisions; however, few of them can address various uncertainties existing in many factors （e.g., eco...A large number of mathematical models were developed for supporting agricultural production structure optimization decisions; however, few of them can address various uncertainties existing in many factors （e.g., eco-social benefit maximization, food security, employment stability and ecosystem balance）. In this study, an interval-probabilistic agricultural production structure optimization model （IPAPSOM） is formulated for tackling uncertainty presented as discrete intervals and/or probability distribution. The developed model improves upon the existing probabilistic programming and inexact optimization approaches. The IPAPSOM considers not only food security policy constraints, but also involves rural households’income increase and eco-environmental conversation, which can effectively reflect various interrelations among different aspects in an agricultural production structure optimization system. Moreover, it can also help examine the reliability of satisfying （or risk of violating） system constraints under uncertainty. The model is applied to a real case of long-term agricultural production structure optimization in Dancheng County, which is located in Henan Province of Central China as one of the major grain producing areas. Interval solutions associated with different risk levels of constraint violation are obtained. The results are useful for generating a range of decision alternatives under various system benefit conditions, and thus helping decision makers to identify the desired agricultural production structure optimization strategy under uncertainty.展开更多
This research assessed empirically the quantitative analysis of some selected food imports of Nigeria (rice, wheat and sugar). Time series data were used to examine the determinant of total food imports and the trend ...This research assessed empirically the quantitative analysis of some selected food imports of Nigeria (rice, wheat and sugar). Time series data were used to examine the determinant of total food imports and the trend in the quantity of the food imported. The secondary data were obtained from institutional and national database over 1981-2010. Descriptive statistics, regression and correlation analysis were used as analytical tools. Statistical analysis shows that food deficit began in the 1970’s, when Nigeria started the importation of food to feed the country. The result of the correlation analysis shows that the postulated determinants of food imports were positively correlated with the quantity of food import. The test for the individual variables shows that;national income explains 40%, external reserves explains 38%, food production index explains 46%, population explains 58% and exchange rate explains 74% of the total variation in the quantity of food import. The over-all goodness of fit of the regression analysis result shows that, the postulated regressors namely, relative price, national income, external reserves, lagged index of domestic food production, population estimate and exchange rate explained approximately 70% of the variability in the quantity of the selected food imports for the period of study. Consequently, there is the need for Nigeria to shift base from the ideology of nationalist orientation, as well as afro centric point of view and move towards unrestrained export-led growth that seeks to develop that market as the first option with corresponding development in international trade. This is however possible by limiting the importation of foods/raw materials that can be sourced for locally, increasing the domestic production of food generally and maintaining a healthy foreign investment with developed countries as a short term measure while in the long run, diversification of the economy, massive investment in agriculture and introduction of population control measures could serve as saviours to lower the rate of increase in food import demand.展开更多
基金Supported by the Key Research Subject of Economic Census of Xinjiang Production and Construction Corps(201004)the President Fund for Natural Science Project of Tarim University(TDZKSS09010)+1 种基金the Quality Project of Tarim University(TDZGKC09085)the Quality Project of Tarim University(TDZGTD09004)
文摘Agricultural input and output status in southern Xinjiang,China is introduced,such as lack of agricultural input,low level of agricultural modernization,excessive fertilizer use,serious damage of environment,shortage of water resources,tremendous pressure on ecological balance,insignificant economic and social benefits of agricultural production in southern Xinjiang,agriculture remaining a weak industry,agricultural economy as the economic subject of southern Xinjiang,and backward economic development of southern Xinjiang.Taking the Aksu area as an example,according to the input and output data in the years 2002-2007,input-output model about regional agriculture of the southern Xinjiang is established by principal component analysis.DPS software is used in the process of solving the model.Then,Eviews software is adopted to revise and test the model in order to analyze and evaluate the economic significance of the results obtained,and to make additional explanations of the relevant model.Since the agricultural economic output is seriously restricted in southern Xinjiang at present,the following countermeasures are put forward,such as adjusting the structure of agricultural land,improving the utilization ratio of land,increasing agricultural input,realizing agricultural modernization,rationally utilizing water resources,maintaining eco-environmental balance,enhancing the awareness of agricultural insurance,minimizing the risk and loss,taking the road of industrialization of characteristic agricultural products,and realizing the transfer of surplus labor force.
基金funded by the National Natural Science Foundation of China (41130748, 41101162)the Key Knowledge Innovation Project of Chinese Academy of Sciences (KZCX2-EW-304)
文摘A large number of mathematical models were developed for supporting agricultural production structure optimization decisions; however, few of them can address various uncertainties existing in many factors （e.g., eco-social benefit maximization, food security, employment stability and ecosystem balance）. In this study, an interval-probabilistic agricultural production structure optimization model （IPAPSOM） is formulated for tackling uncertainty presented as discrete intervals and/or probability distribution. The developed model improves upon the existing probabilistic programming and inexact optimization approaches. The IPAPSOM considers not only food security policy constraints, but also involves rural households’income increase and eco-environmental conversation, which can effectively reflect various interrelations among different aspects in an agricultural production structure optimization system. Moreover, it can also help examine the reliability of satisfying （or risk of violating） system constraints under uncertainty. The model is applied to a real case of long-term agricultural production structure optimization in Dancheng County, which is located in Henan Province of Central China as one of the major grain producing areas. Interval solutions associated with different risk levels of constraint violation are obtained. The results are useful for generating a range of decision alternatives under various system benefit conditions, and thus helping decision makers to identify the desired agricultural production structure optimization strategy under uncertainty.
文摘This research assessed empirically the quantitative analysis of some selected food imports of Nigeria (rice, wheat and sugar). Time series data were used to examine the determinant of total food imports and the trend in the quantity of the food imported. The secondary data were obtained from institutional and national database over 1981-2010. Descriptive statistics, regression and correlation analysis were used as analytical tools. Statistical analysis shows that food deficit began in the 1970’s, when Nigeria started the importation of food to feed the country. The result of the correlation analysis shows that the postulated determinants of food imports were positively correlated with the quantity of food import. The test for the individual variables shows that;national income explains 40%, external reserves explains 38%, food production index explains 46%, population explains 58% and exchange rate explains 74% of the total variation in the quantity of food import. The over-all goodness of fit of the regression analysis result shows that, the postulated regressors namely, relative price, national income, external reserves, lagged index of domestic food production, population estimate and exchange rate explained approximately 70% of the variability in the quantity of the selected food imports for the period of study. Consequently, there is the need for Nigeria to shift base from the ideology of nationalist orientation, as well as afro centric point of view and move towards unrestrained export-led growth that seeks to develop that market as the first option with corresponding development in international trade. This is however possible by limiting the importation of foods/raw materials that can be sourced for locally, increasing the domestic production of food generally and maintaining a healthy foreign investment with developed countries as a short term measure while in the long run, diversification of the economy, massive investment in agriculture and introduction of population control measures could serve as saviours to lower the rate of increase in food import demand.
