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101.
102.
M.-C. Gerbet 《Journal of Medieval History》1991,17(4)
Despite a few pioneering studies into transhumant raising in the kingdom of Castile much work in this field has yet to be done. We are acquainted with its general organisation but more rarely with its local manifestations. On the whole we know of the revenues it yielded to the Crown but less of those it delivered to the lords. It was during a lawsuit brought by the Mesta at the end of the fifteenth century against the lord of Capilla, whom it accused of imposing illegal taxes upon the migration of the winter herds across the Capilla bridge on their way to the Extranadura of the south, that a rich documentation was collected by the incriminated party. This documentation holds a twofold interest for us: first it informs us about the region of origin of the animals which followed this migration, the number of herds involved, their composition and their owners and shepherds; second it gives us knowledge of the revenues which a lord could extract from the collection of taxes imposed on the migration, or transhumance, itself. 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
108.
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
109.
Bruce L. Rhoads 《Geographical analysis》1991,23(4):346-361
Simultaneous-equation statistical models are an attractive method for directly analyzing interactions among components of geomorphic systems. This study demonstrates that the utility of simultaneous-equation analysis is limited for fluvial systems by inherent multicollinearity among hydrologic and morphologic variables. Although multicollinearity for observed data may not be severe, estimation procedures for simultaneous-equation models often enhance this multicollinearity to problematic levels. Diagnostic tests are applied to three models of fluvial systems to illustrate the severity of the problem. It is recommended that investigators who develop simultaneous-equation models perform appropriate diagnostic evaluations to determine the impact of multicollinearity on specific parameter estimates. 相似文献
110.
Is the Suburban Railway System a Fractal? 总被引:2,自引:0,他引:2