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951.
The authors investigate an agriculturally based policy for improving rural incomes and for retarding the rural-urban migration flow. The production of agricultural goods is characterized by a production function in which output increases with increases in agricultural labor inputs, capital, public infrastructure, land, and technology. Differences among regions in agricultural technology will reflect regional differences in education, the institutionalized form of productive organization, and differences in access to technological information channeled through more technically advanced cities. To pick up the effect of out-migration changes in state agricultural labor supply and upon agricultural output, the state's agricultural out-migration rate is included together with the agricultural labor force. The gross migrant flow between 2 locations is hypothesized to depend upon a set of variables influencing the individual's perception of the economic rate of return to be gained by moving, a set of variables reflecting the individual's propensity to relocate, the labor displacement effects of investments, and the at risk population at 1 location available to migrate. It is also taken into account that individuals differ in their response to information about origin and destination wage differentials and that individuals may or may not perceive a new ecnomic gain from migration but may base the decision on other considerations. Results of a statistical analysis using data from the Mexican census of population for 1960 and 1970 are: 1) size of the rural labor force was negatively associated with agricultural wages, contrary to expectations; 2) small farmers have benefited from the expansion of irrigation in Mexico; and 3) higher urban wages attract migration, and higher growth rate of agricultural income retards rural-urban migration. With respect to the 1950-60 decade both agricultural income and rural out-migration impacts could have been substantial but both the impact on local urban growth and on the rate of in-migration to the primate city would have been slight. 相似文献
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M. PICON C. CARRE M. L. CORDOLIANI M. VICHY J. A. HERNANDEZ J. L. MIGNARD 《Archaeometry》1975,17(2):191-199
The composition diagrams of the La Graufesenque, Banassac and Montans Terra Sigillata are given as well as a calculation method to improve the separation between the workshops with compositions which are very similar. This method can then be generalized. 相似文献
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The remanent magnetization of samples spanning Zones I to III of the Hoxnian Interglacial at Hoxne has declination values that lie within 30° of the present-day declination, and inclination values that are not more than 10° steeper or 20° shallower than the present-day inclination. 相似文献
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