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Registros recuperados: 22
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THE RELATIONSHIP BETWEEN FARM SIZE AND THE TECHNICAL INEFFICIENCY OF PRODUCTION OF WHEAT FARMERS IN THE EASTERN FREE STATE AgEcon
van Zyl, Johan; Thirtle, Colin G..
Some comments are required to put in perspective the results obtained by Ngwenya, Battese and Fleming (1997). In particular, it is necessary to examine their main conclusion that in 1988/89 there was a significant inverse relationship between the technical inefficiency of wheat farmers in the Eastern Free State and farm size, because this is in direct contrast with the findings of Van Zyl, Binswanger and Thirtle (1995) who used the same dataset.
Tipo: Report Palavras-chave: Crop Production/Industries.
Ano: 1998 URL: http://purl.umn.edu/56717
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Monsanto's Adventures in Zulu Land: Output and Labour Effects of GM Maize and Minimum Tillage AgEcon
Gouse, Marnus; Piesse, Jenifer; Thirtle, Colin G..
The only commercial genetically modified (GM) subsistence food crop is white maize in South Africa, which was released in 2001/2. This paper reports on the performance of insect resistant (Bt) white maize grown by smallholders in Hlabisa, KwaZulu Natal, where the other development is minimum tillage. The results show that, contrary to many inflated claims, in the dry 2003/4 season, there was no significant difference between the yield per kg of seed for Bt and conventional maize, due to very low stalk borer infestation levels. Farmers who planted Bt maize in 2003/2004 were thus worse off as they paid more for seed and obtained no benefit. This is measured using efficiency scores from a stochastic frontier analysis. These results conflict with the yield per...
Tipo: Conference Paper or Presentation Palavras-chave: Agribusiness; Crop Production/Industries; Research and Development/Tech Change/Emerging Technologies; O33; Q16.
Ano: 2006 URL: http://purl.umn.edu/25309
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What is the appropriate level of aggregation for productivity indices? Comparing district, regional and national measures AgEcon
Conradie, Beatrice; Piesse, Jenifer; Thirtle, Colin G..
This paper examines the appropriate level of aggregation for the construction of total factor productivity (TFP) indices. The dataset covers the magisterial districts and statistical regions of the Western Cape for the years 1952 to 2002. Over these five decades agricultural production in the Western Cape grew twice as fast as in the country as a whole but this average masks substantial regional variation. Results show that TFP growth was negative in the Karoo, moderate in the Swartland, Overberg and Southern Cape, and generally above 2% per year in the Boland and Breede River Valleys, where there is extensive irrigation.
Tipo: Journal Article Palavras-chave: Total factor productivity; Western Cape; South Africa; Agribusiness.
Ano: 2009 URL: http://purl.umn.edu/49162
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Machinery and labour biases of technical change in South African agriculture: A cost function approach AgEcon
Townsend, Rob F.; van Zyl, Johan; Thirtle, Colin G..
This paper provides an empirical investigation into the long-standing notion of biases of technical change in South African agriculture. The second order cost function is used to derive relative bias measures between labour and machinery. The results suggest that large machinery-using biases in technology have been developed with minimal labour-using biases.
Tipo: Journal Article Palavras-chave: Farm Management; Research and Development/Tech Change/Emerging Technologies.
Ano: 1997 URL: http://purl.umn.edu/54448
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Book reviews AgEcon
Anderson, Jock R.; Saunders, Caroline M.; Thirtle, Colin G.; Nightingale, John J..
Tipo: Article Palavras-chave: Teaching/Communication/Extension/Profession.
Ano: 2002 URL: http://purl.umn.edu/119000
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THE RATE OF RETURN ON EXPENDITURES OF THE SOUTH AFRICAN AGRICULTURAL RESEARCH COUNCIL (ARC) AgEcon
Thirtle, Colin G.; Townsend, Rob F.; Amadi, Juliana; Lusigi, Angela; van Zyl, Johan.
All the rate of return estimates, regardless of methodology or the level of aggregation, are entirely consistent and logical. The returns show that the ARC has been extremely successful economically and has followed a sound strategy of exploiting spillovers from foreign R&D systems. However, there must be a strong socio-economic component to the ARC's efforts if it is to reach the disadvantaged.
Tipo: Journal Article Palavras-chave: Research and Development/Tech Change/Emerging Technologies.
Ano: 1998 URL: http://purl.umn.edu/54904
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The Role of Demand and Supply in the Generation and Diffusion of Technical Change AgEcon
Thirtle, Colin G.; Ruttan, Vernon W..
Tipo: Working or Discussion Paper Palavras-chave: Demand and Price Analysis; Research and Development/Tech Change/Emerging Technologies.
Ano: 1986 URL: http://purl.umn.edu/7522
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Modelling efficiency with farm-produced inputs: dairying in KwaZulu-Natal, South Africa AgEcon
Mkhabela, Thulasizwe S.; Piesse, Jenifer; Thirtle, Colin G.; Vink, Nick.
This paper models dairy farms in KwaZulu-Natal, South Africa, emphasising the complexities unique to this multi-product industry. Net and gross output approaches to measuring production are discussed and then tested using panel data from 37 dairy farms in KwaZulu-Natal from 1999 and 2007. Production functions for the three outputs: milk production, animals and farm-produced feed, are fitted as a simultaneous system to model the farms’ production activities. This simultaneous model is complemented by a single equation reduced form that is fitted as a frontier, which allows estimation of the relative efficiencies of the individual farms. The results show that, with data this detailed, it is possible to refine the model until it fits very tightly. Indeed, in...
Tipo: Journal Article Palavras-chave: Dairy farms; Production; Frontiers; Efficiency; Production Economics.
Ano: 2010 URL: http://purl.umn.edu/61999
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Efficiency and Pooling in Western Cape Wine Grape Production AgEcon
Conradie, Beatrice; Cookson, Graham; Thirtle, Colin G..
This paper uses a stochastic frontier and inefficiency model to test the efficiency of grape production in the Western Cape. The data covers two panels of wine grape farms (34 in Robertson and 36 in Worcester) for 2003 and 2004 and 37 table grape farms in De Doorns for 2004 only. Tests show that Cobb Douglas stochastic production frontiers, with variables to explain the inefficiencies are an appropriate representation of the five individual samples. The stochastic frontier results indicate that output can be explained by land, labour and machinery and that efficiency cab be affected by labour quality, age and education of the farmer, location, the percentage of non-bearing vines and expenditures on electricity for irrigation. These data is sufficiently...
Tipo: Conference Paper or Presentation Palavras-chave: Crop Production/Industries; O13; Q12.
Ano: 2006 URL: http://purl.umn.edu/25522
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Agricultural technology, productivity and employment: Policies for poverty reduction AgEcon
Thirtle, Colin G.; Piesse, Jenifer; Gouse, Marnus.
This paper begins by arguing that agricultural economics has an important contribution to make to the economic transition of the new democratic South Africa. Policies are required to reduce unemployment, poverty and inequality, but does the work of agricultural economists provide the policy makers with the information necessary to make the correct choices? In this context, we update our recent work on technology, efficiency and productivity in South African agriculture, for both the commercial and smallholder sub-sectors. For the commercial sector, this means extending the total factor productivity index and estimates of the demand for labour. For the smallholder sector, there are new results on the impacts of GM cotton and white maize on output and...
Tipo: Journal Article Palavras-chave: Agricultural and Food Policy; Food Security and Poverty.
Ano: 2005 URL: http://purl.umn.edu/31719
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Is African agriculture converging? Evidence from a panel of crop yields AgEcon
Lusigi, Angela; McDonald, Scott; Roberts, Jennifer R.; Thirtle, Colin G..
Tipo: Journal Article Palavras-chave: Crop Production/Industries.
Ano: 2000 URL: http://purl.umn.edu/54197
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Stochastic biases in technical change in South African agriculture AgEcon
Balcombe, Kelvin George; Bailey, Alastair; Morrison, Jamie; Rapsomanikis, George; Thirtle, Colin G..
This paper examines biased technical change in South African agriculture using a system of share equations with unobserved components. Developing on the work of Lambert and Shonkwiler (1995), this paper generalises previous work by introducing independent unobserved components into each model using a regression-based approach. We find evidence of stochastic technical change, which is itself biased between the four factors of production: machinery, land, labour and fertiliser, and which closely reflects distinct phases of South African agricultural policy and development.
Tipo: Journal Article Palavras-chave: Research and Development/Tech Change/Emerging Technologies.
Ano: 2000 URL: http://purl.umn.edu/54211
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THE IMPACT OF RESEARCH LED AGRICULTURAL PRODUCTIVITY GROWTH ON POVERTY REDUCTION IN AFRICA, ASIA AND LATIN AMERICA AgEcon
Thirtle, Colin G.; Lin, Lin; Piesse, Jenifer.
Twenty percent of the world population, or 1.2 billion live on less than $1 per day; 70% of these are rural and 90% in Asia and Sub-Saharan Africa. Research led technological change in agriculture generates sufficient productivity growth to give high rates of return in African and Asia and has a substantial impact on poverty, currently reducing this number by 27 million per annum, whereas productivity growth in industry and services has no impact. The per capita "cost" of poverty reduction by means of agricultural research expenditures in Africa is $144 and in Asia $180, or 50 cents per day, but this is covered by output growth. By contrast, the per capita cost for the richer countries of Latin America is over $11,000.
Tipo: Conference Paper or Presentation Palavras-chave: Agricultural Productivity; Poverty Reduction; Food Security and Poverty; Research and Development/Tech Change/Emerging Technologies; 011; 013; 015.
Ano: 2003 URL: http://purl.umn.edu/25834
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PUBLIC SECTOR PLANT BREEDING IN A PRIVATIZING WORLD AgEcon
Thirtle, Colin G.; Srinivasan, Chittur S.; Heisey, Paul W..
Intellectual property protection, globalization, and pressure on public budgets in many industrialized countries have shifted the balance of plant breeding activity from the public to the private sector. Several economic factors influence the relative shares of public versus private sector plant breeding activity, with varying results over time, over country, and over crop. The private sector, for example, dominates corn breeding throughout the industrialized world, but public and private activities in wheat breeding differ widely in Western Europe, different regions of the United States, Canada, and Australia. Public sector involvement in plant breeding may have benefits to society that the private sector's activities may not, fostering greater sharing of...
Tipo: Report Palavras-chave: Plant breeding; Economics; Public sector; Private sector; Research policy; Biotechnology; Intellectual property; Crop Production/Industries; Research and Development/Tech Change/Emerging Technologies.
Ano: 2001 URL: http://purl.umn.edu/33775
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FINANCIAL EXPOSURE, TECHNICAL CHANGE AND FARM EFFICIENCY: EVIDENCE FROM THE ENGLAND AND WALES DAIRY SECTOR AgEcon
Hadley, David; Shankar, Bhavani; Thirtle, Colin G.; Coelli, Tim J..
This paper fits a translog stochastic production frontier with inefficiency effects to a panel of 693 UK dairy farms for the period from 1982 to 1997. The Cobb Douglas is rejected as inadequate relative to the less restrictive translog functional form and the frontier model is statistically superior to the mean response function, despite the fact that on average the farms were 87% efficient. Technological progress, at 1.7% per annum, is the dominant force, but efficiency declined at 0.8% per year, which reduced productivity growth to 0.9% per annum. The inefficiencies are explained in the second stage of the model, where the greatest cause is financial exposure, captured here by the ratio of debts to assets. Older farmers, those in less favoured areas and...
Tipo: Conference Paper or Presentation Palavras-chave: Livestock Production/Industries.
Ano: 2001 URL: http://purl.umn.edu/20656
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Assessing the benefits of research expenditures on maize production in South Africa AgEcon
Townsend, Rob F.; van Zyl, Johan; Thirtle, Colin G..
This paper focuses on assessing the benefits of research expenditures on maize production in South Africa. Both the production and supply function approaches are used to calculate elasticities of research expenditure on output and yield. Cointegration is used to establish long-run relationships between variables in these models. The lag structure of R&D expenditures on output is examined making use of the unrestricted, polynomial, beta and gamma distributions. The coefficients of these lag distributions were then used to calculate a rate of return to maize research expenditure, which was estimated as being between 28% and 39% per annum. These rates of return are high, mitigating in favour of more research expenditure rather than less.
Tipo: Journal Article Palavras-chave: Crop Production/Industries; Research and Development/Tech Change/Emerging Technologies.
Ano: 1997 URL: http://purl.umn.edu/54718
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CAN GM-TECHNOLOGIES HELP AFRICAN SMALLHOLDERS? THE IMPACT OF BT COTTON IN THE MAKHATHINI FLATS OF KWAZULU-NATAL AgEcon
Beyers, Lindie; Thirtle, Colin G..
Analysis of a survey of the 1998-99 and 1999-2000 seasons for the same 100 smallholders in the Makhathini Flats region of KwaZulu-Natal shows that Bt cotton has performed better than other varieties. Having two years of data for the same farmers allows innate efficiency differences, due to factors such as farm size, to be separated from the effects of the new technology, which is not normally possible. Farmers who adopted Bt cotton in 1999-2000 benefited according to all the measures used. Higher yields and lower chemical costs outweighed higher seed costs, giving higher gross margins. These measures showed negative benefits in 1998-99, which conflicts with continued adoption, but stochastic efficiency frontier estimation, which takes account of the...
Tipo: Conference Paper or Presentation Palavras-chave: KwaZulu-Natal; Bt cotton; Stochastic Frontiers; Efficiency; Crop Production/Industries; Research and Development/Tech Change/Emerging Technologies.
Ano: 2003 URL: http://purl.umn.edu/25922
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HERD SIZE AND EFFICIENCY ON MIXED CROP AND LIVESTOCK FARMS: CASE STUDIES OF CHIWESHE AND GOKWE, ZIMBABWE AgEcon
Muchena, M.; Piesse, Jenifer; Thirtle, Colin G.; Townsend, Rob F..
This study is based on two 1991 sample surveys, each of ninety farms, in the predominantly arable region of Chiweshe and in the low rainfall area of Gokwe, where animals are more important. The two samples are reasonably representative of the range of conditions found in the communal areas in Zimbabwe. Programming techniques are used to determine the efficiency levels of the farms in each region. The results show that efficiency is positively related to the numbers of both cows and oxen, with only a few farms in Gokwe possibly having too many animals. Farms in Gokwe are on average about two thirds as efficient as those in Chiweshe, which is a measure of the effects of the poorer climate and soils. Non-farm income is also lower, due to lesser opportunities...
Tipo: Journal Article Palavras-chave: Farm Management; Livestock Production/Industries.
Ano: 1997 URL: http://purl.umn.edu/54978
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Multi-factor agricultural productivity and convergence in Botswana, 1981-96 AgEcon
Thirtle, Colin G.; Lusigi, Angela; Piesse, Jenifer; Suhariyanto, Kecuk.
This paper calculates multi-lateral Malmquist multi-factor productivity (MFP) indices for agriculture in the eighteen regions and the commercial sector of Botswana from 1981 to 1996. The Malmquist is appropriate because prices do really exist for major inputs such as land and labour. The small size of the cross section is overcome by using the sequential version of the Malmquist, which accumulates the annual data, so increasing the stability of the frontier. The regional MFPs are the natural peer group for producing a national MFP, so the problem of choosing peers, in earlier work on international comparisons does not arise. The results show that the national MFP grew at an average rate 1.57% per annum. However, disaggregation by enterprise shows that the...
Tipo: Journal Article Palavras-chave: Productivity Analysis.
Ano: 2000 URL: http://purl.umn.edu/54228
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TECHNOLOGICAL CHANGE AND THE PRODUCTIVITY SLOWDOWN IN FIELD CROPS: UNITED STATES, 1939-78 AgEcon
Thirtle, Colin G..
In the past four decades, productivity in United States field crops has been transformed by the mechanical and fertilizer revolutions. Since input data are typically not available by crop, most investigators of productivity have been at the aggregate level. This paper developps a simultaneous equation, partial adjustment model of the demand of inputs, which generates estimates of the technical change parameters for wheat, corn, soybeans, and cotton. These estimates allow comparisons of the factor saving biases in technical change, leading to a novel test of the induced innovation hypothesis and the suggestion that the productivity slowdown may yet affect agriculture in the United States.
Tipo: Journal Article Palavras-chave: Research and Development/Tech Change/Emerging Technologies.
Ano: 1985 URL: http://purl.umn.edu/29969
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