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91.
92.
Characteristics of communal club members who use input packages are studied using a survey of communal clubs serviced by Africa Co‐operative Action Trust (Acat) in KwaZulu during 1989. Discriminant analysis shows that full input package adopters tend to belong to older clubs, have less formal savings and receive more visits each year from KwaZulu Department of Agriculture (KDA) extension officers. They also have a greater proportion of land under sugar‐cane, larger farm sizes and a higher rand monetary value of livestock.

Members of older clubs benefit from greater club experience in ordering inputs and liquidity for securing discounts on bulk orders. Clubs also enable scarce KDA extension manpower resources to be used more effectively by focusing extension efforts on groups rather than individual farmers. Sugar‐cane production probably indicates member willingness to innovate and the availability of funds to buy complete input packages for other crops. Increased access to land promotes input package adoption which can raise agricultural productivity. Development of institutional arrangements for a land rental market in KwaZulu should be considered. Higher monetary values of livestock reflect Increased ability to bear risk associated with technology adoption and that adopters have the means to purchase input packages  相似文献   

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The aim of the paper is to investigate certain aspects of the post‐adoption behaviour of dryland cotton farmers in the Ubombo and Hlabisa magisterial districts of KwaZulu. Particular attention is paid to the socio‐economic determinants of the success (returns per hectare) of the household cotton enterprise.

Multi‐stage sampling methods were used to draw a random sample of fifty cotton‐farming households from each of the two study districts. The data were collected by interview survey and analysed using principal components and regression techniques.

Results suggest that the success of the household enterprise in both areas is largely determined by the socio‐economic environment under which the producer operates. The most important success‐determining factors are those relating to the human capital endowments and economic status of the household.  相似文献   

95.
Simulated annealing: An introduction   总被引:1,自引:0,他引:1  
  相似文献   
96.
This note uses the Theorem of the Alternative to prove new results on the implementability of general, asymmetric auctions, and to provide simpler proofs of known results for symmetric auctions. The tradeoff is that type spaces are taken to be finite.  相似文献   
97.
We present general results for finding or boundingt maxB , the maximum number of arbitrary whole blocks of observations which can be removed from a block design, and still leave all of the elementary treatment contrasts estimable. The block sizes may be larger than the number of treatments. The results are applied to BBDs, reinforced BIBDs and BBDs, BTIBDs, and a series of variance balanced incomplete block designs with two block sizes. Also given for most of these designs, are results fort max, the maximum number of arbitrary, scattered observations that can become unavailable, and still leave all of the elementary treatment contrasts estimable.The work was undertaken while Dr. Whittinghill was visiting Ohio State University, and supported by a grant from the Natural Sciences Division, Colby College, Waterville, Maine.  相似文献   
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In recent years there has been a growing number of input-output models of economies ranging in scale from the rural to the national. While offering invaluable insights into the interaction of sectors within an economy, the input-output model suffers from the fact that its coefficient values are altered over time due particularly to technological change. Two of the prominent techniques designed to update these technical coefficients, the RAS and linear programming methods, are compared herein with regard to changes in U.S. national coefficients between 1963 and 1967. Suggestions for improvements to the latter method are outlined.  相似文献   
100.
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