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G L Townsend 《Journal of the history of medicine and allied sciences》1967,22(3):286-316
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Neil C. Field 《The Canadian geographer》1991,35(1):23-36
This paper describes a system of versatile software packages that has been developed by the author for population analysis on IBM-compatible microcomputers using PC or MS DOS. The series includes programs for the production of life tables, the analysis of spatial patterns and temporal trends in mortality, population projections, stationary-state population simulations and demographic planning, cohort survival estimates of net migration, and the analysis of migration matrices. Each of the programs in the series is discussed in terms of its principal analytical features, associated conceptual and methodological issues, and potential applications. The programs are intended for use both as basic research and planning tools and as instructional aids in university-level courses. The programs and related documentation are available on a set of four 360K diskettes. 相似文献
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Denise L. Stanley 《Development and change》1991,22(4):757-779
Natural resource tenure and economic feasibility of resource-based activities are two of the most important issues in the current debate around environmental degradation and rural poverty. While many analyses have blamed the ‘tragedy of the commons’ and government mismanagement for environmental destruction, this paper provides a case study of resin tapping in Honduras which formulates the hypotheses that common property regimes can be successful and that economic liberalization policies may be detrimental to community-level resource schemes. Over half of the 6000 farmer-resin tappers in Honduras are organized into forty-six co-operatives that market the tree sap, wood and other forest products. These activities combine the twin goals of community-based forest preservation and income generation. Established legally in 1974, the tapping groups have expanded to include a variety of organizational and technical arrangements. The two co-operatives of Villa Santa and San Juan de Ojojona demonstrate contrasting histories, ecological endowments and economic outcomes. Currently the Honduran resin tappers are facing problems over their access to forest resources, the fluctuating profitability of extractive activities and the stability of the co-operative organization. These three issues are relevant to a variety of community-based environmental activities, and the lessons of the Honduran experience can be applied to analyse the processes of environmental degradation and community response elsewhere in the Third World. 相似文献
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In this paper, we first develop a measure of total factor productivity (TFP) growth and summarize a source-of-growth analysis for the manufacturing sector of 48 states. As have others, we find little association between TFP growth differentials and output growth differentials for census regions. At the staterather than the regional level, however, we find a positive association between TFP growth and output growth. We use cross-sectional data to estimate the determinants of the variation in TFP growth. Two results emerge that are important for regional policy and for understanding national productivity trends. First, state investments in education and in transportation infrastructure may affect TFP growth. Second, energy price increases in the early 1970s had no differential effects on productivity growth across states. We also explore the determinants of manufacturing output growth and find that TFP growth, demand growth, wage growth, wage levels, and state corporate income tax rates are significant. 相似文献