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AGGREGATION ISSUES IN PEST CONTROL ECONOMICS: A BIOECONOMIC APPROACH AgEcon
Young, Douglas L.; Smith, Elwin G.; Kwon, Tae-Jin.
Previous research has defined “aggregate pesticide expenditures” as the control variable; however, virtually all managerial recommendations and environmental restrictions target specific pesticides, rates, and crops. A bioeconomic approach considering particular pesticides on specific pests and crops is recommended for managerial-policy applications and testing for increasing returns. Exponential weed control and seven popular yield damage functional forms were estimated for a bioeconomic weed control model for winter wheat in Washington. Concavity with respect to herbicide rate was observed for most popular damage functions at normal weed densities and manufacturers’ label rates, but convexity existed outside these ranges and should be checked.
Tipo: Conference Paper or Presentation Palavras-chave: Bioeconomic; Data aggregation; Herbicide; Increasing returns; Pest control; Pesticide; Weed; Crop Production/Industries.
Ano: 2000 URL: http://purl.umn.edu/36448
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Definitions of Biodiversity and Measures of Its Value AgEcon
Simpson, R. David.
The destruction of natural habitats has prompted concerns about the loss of biological diversity. Regrettably, however, there is no consensus among either biologists or economists on the most meaningful measures of biodiversity. Fundamentally different definitions are useful in asking fundamentally different questions. Considerable attention has been given to the value of diversity in search models. A measure of "aggregate variability" is appropriate to such models. Values derived from search models tend to be well behaved; they exhibit diminishing returns in diversity. In contrast, a definition of diversity as "relative abundance" is more appropriate to more complex objective functions. Values derived in these models are not necessarily well behaved. The...
Tipo: Working or Discussion Paper Palavras-chave: Biological diversity; Biodiversity; Diversity index; Abundance; Search; Variability; Consistency; Contingent valuation; Diminishing returns; Increasing returns; Environmental Economics and Policy; D43; D83; Q20.
Ano: 2002 URL: http://purl.umn.edu/10551
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Efficiency in Damage Control Inputs: A Stochastic Production Frontier Approach AgEcon
Karagiannis, Giannis; Tsionas, Efthimios; Tzouvelekas, Vangelis.
The present paper extents the existing literature providing a theoretically consistent framework for measuring input-specific technical efficiency in damage control inputs within a stochastic production frontier model. The theoretical framework for modeling damage control agents is based on Fox and Weersink (1995) model specification that allows for increasing returns on damage control inputs. The empirical model accounts veterinary expenses as the damage control input and it is applied on a panel data set of sheep farms in Greece during the 1989-92 period. The results suggest that sheep farms in Greece are using inefficiently immunization and antibiotics in their flock as their average technical efficiency level was 72.82%. On the other hand, technical...
Tipo: Conference Paper or Presentation Palavras-chave: Increasing returns; Input-specific technical efficiency; Damage and control function; Sheep farms; Greece; Farm Management; Q12; Q16; C23; C51.
Ano: 2005 URL: http://purl.umn.edu/24642
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