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Registros recuperados: 6
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Research returns redux: a meta-analysis of the returns to agricultural R&D AgEcon
Alston, Julian M.; Marra, Michele C.; Pardey, Philip G.; Wyatt, T.J..
A total of 289 studies of returns to agricultural R&D were compiled and these provide 1821 estimates of rates of return. After removing statistical outliers and incomplete observations, across the remaining 1128 observations the estimated annual rates of return averaged 65 per cent overall — 80 per cent for research only, 80 per cent for extension only, and 47 per cent for research and extension combined. These averages reveal little meaningful information from a large body of literature, which provides rate‐of‐return estimates that are often not directly comparable. This study was aimed at trying to account for the differences. Several features of the methods used by research evaluators matter, in particular assumptions about lag lengths and the...
Tipo: Journal Article Palavras-chave: Research and Development/Tech Change/Emerging Technologies.
Ano: 2000 URL: http://purl.umn.edu/117834
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SUBSIDIZED FERTILIZER IN THE SAHEL: THAT IS THE QUESTION AgEcon
Wyatt, T.J.; Samake, Odiaba; Tiendrebeogo, Jean-Pierre.
Nutrient depletion concerns researchers and policy makers in the Sahel. A village-level programming model determines the size of fertilizer subsidy necessary to encourage farmers to apply the recommended dosage to their millet fields. Results indicate that subsidies would be extremely costly and less than half the expenditures accrue to the farm-household.
Tipo: Conference Paper or Presentation Palavras-chave: Agricultural and Food Policy; Land Economics/Use.
Ano: 1999 URL: http://purl.umn.edu/21650
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RESEARCH RETURNS REDUX: A META-ANALYSIS OF THE RETURNS TO AGRICULTURAL R&D AgEcon
Alston, Julian M.; Marra, Michele C.; Pardey, Philip G.; Wyatt, T.J..
A total of 294 studies of returns to agricultural R&D (including extension) were compiled and these studies provide 1,858 separate estimates of rates of return. This includes some extreme values, which are implausible. Then the highest and lowest 2.5 percent of the rates of return were set aside, the estimated annual rates of return averaged 73 percent overall—88 percent for research only, 45 percent for research and extension, and 79 percent for extension only. But these averages reveal little meaningful information from a large and diverse body of literature, which provides rate-of –return estimates that are often not directly comparable. The purpose of this study was to go behind the average, and try to account for the sources of differences, in a...
Tipo: Working or Discussion Paper Palavras-chave: Research and Development/Tech Change/Emerging Technologies.
Ano: 1998 URL: http://purl.umn.edu/16056
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A META-ANALYSIS OF RATES OF RETURN TO AGRICULTURAL R & D: EX PEDE HERCULEM? AgEcon
Alston, Julian M.; Chan-Kang, Connie; Marra, Michele C.; Pardey, Philip G.; Wyatt, T.J..
Tipo: Report Palavras-chave: Research and Development/Tech Change/Emerging Technologies.
Ano: 2000 URL: http://purl.umn.edu/16535
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INSECT POPULATION DYNAMICS, PESTICIDE USE AND FARMWORKER HEALTH REVISITED: PESTICIDE CHOICE AND RISK MITIGATION AgEcon
Wyatt, T.J..
Several policies to reduce worker exposure, dietary and environmental risks are examined in the context of pesticide choice driven by insect population dynamics. Restricted entry policies and taxes have differing impacts for individual and aggregate risks. Limits on application rates have the most consistent impacts on risk.
Tipo: Conference Paper or Presentation Palavras-chave: Pesticide choice; Human health risks; Environmental risks; Endosulfan; Lettuce; Crop Production/Industries.
Ano: 2002 URL: http://purl.umn.edu/19850
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SPATIAL HETEROGENEITY, MOBILITY AND ACCESS: THE CASE OF RANGE MANAGEMENT IN THE SAHEL AgEcon
Sanchirico, James N.; Wyatt, T.J..
In this paper, we develop and calibrate a spatial and intertemporal bioeconomic model of livestock production to the West African Sahel region. The model is then used to investigate the effects of land heterogeneity, range scale, and access rights on long term management of rangeland in the Sahel.
Tipo: Conference Paper or Presentation Palavras-chave: Livestock Production/Industries.
Ano: 1999 URL: http://purl.umn.edu/21563
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