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Aggregation Theory for Incomplete Systems AgEcon
LaFrance, Jeffrey T.; Beatty, Timothy K.M.; Pope, Rulon D..
Gorman's theory of demand is extended comprehensively to incomplete systems. The incomplete systems approach dramatically increases this class of models. The separate roles of symmetry and adding up are identified in the rank and the functional form of this class of models. We show that symmetry determines rank and the maximum rank is three. We show that adding up and 0o homogeneity determines the functional form and there is no functional form restriction for an incomplete system. We prove that every full rank system and reduced rank systems with a minimal level of degeneracy can be written as a polynomial in a single function of income. A complete set of closed form solutions for the indirect objective functions of this class of models is derived. A...
Tipo: Working or Discussion Paper Palavras-chave: Aggregation; Rank; Functional form; Integrability; Incomplete systems; Weak integrability; Demand and Price Analysis; D12; E21.
Ano: 2005 URL: http://purl.umn.edu/25033
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Building Gorman's Nest AgEcon
LaFrance, Jeffrey T.; Beatty, Timothy K.M.; Pope, Rulon D..
Gorman Engel curves are extended to incomplete systems. The roles of Slutsky symmetry and homogeneity/adding up are isolated in the rank and functional form restrictions for Gorman systems. Symmetry determines the rank condition. The maximum rank is three for incomplete and complete systems. Homogeneity/adding up determines the functional form restrictions in complete systems. There is no restriction on functional form in an incomplete system. Every full rank and minimal deficit reduced rank Gorman system has a representation as a polynomial in a single function of income. This generates a complete taxonomy of indirect preferences for Gorman systems. Using this taxonomy, we develop models of incomplete Gorman systems that nest rank and functional form and...
Tipo: Working or Discussion Paper Palavras-chave: Aggregation; Functional form; Gorman Engel curves; Incomplete demand systems; Rank; Weak integrability; Demand and Price Analysis; D12; E21.
Ano: 2004 URL: http://purl.umn.edu/25027
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Full Rank Rational Demand Systems AgEcon
LaFrance, Jeffrey T.; Pope, Rulon D..
We extend the set of full rank nominal and deflated income demand systems to rational demand systems of any rank and present a unifying expression for the indirect preferences of all full rank demand models.
Tipo: Working or Discussion Paper Palavras-chave: Aggregation; Functional form; Integrability; Rank; Rational demand systems; Demand and Price Analysis; D12; E21.
Ano: 2006 URL: http://purl.umn.edu/7152
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HEDONIC ESTIMATION APPLIED TO THE FARMLAND MARKET IN GEORGIA AgEcon
Elad, Renata L.; Clifton, Ivery D.; Epperson, James E..
Farmland offered for its productive or consumptive value may be viewed as a class of goods characteristic of product differentiation. Using the generalized Box-Cox transformation, an unrestricted hedonic model was employed to derive implicit valuations of parcel attributes. Results suggest that the significance and level of importance of attributes on land pricing depends on the spatial extent of markets in Georgia. Differences in the productive or consumptive use of farmland may imply that different factors and functional forms are appropriate to different farmland markets.
Tipo: Journal Article Palavras-chave: Farmland prices; Functional form; Hedonic pricing; Land Economics/Use.
Ano: 1994 URL: http://purl.umn.edu/15179
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MULTIDIMENSIONAL EVALUATION OF FLEXIBLE FUNCTIONAL FORMS FOR PRODUCTION ANALYSIS AgEcon
Ornelas, Fermin S.; Shumway, C. Richard.
Several common flexible functional forms are evaluated for Texas agricultural production utilizing three procedures. Nested hypothesis tests indicate that the normalized quadratic is the marginally-preferred functional form followed by the generalized Leontief. Predictive accuracy results are ambiguous between the generalized Leontief and the normalized quadratic. Statistical performance favors the normalized quadratic. These two functional forms consistently dominate the translog.
Tipo: Journal Article Palavras-chave: Box-Cox; Functional form; Prediction; Production; Statistical performance; Production Economics.
Ano: 1993 URL: http://purl.umn.edu/15046
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On the Solutions to Full Rank Three Gorman Systems AgEcon
LaFrance, Jeffrey T..
This letter closes a gap in the set of solutions for the full rank three systems of Gorman Engel curves and presents a unified expression for the indirect preferences in this case.
Tipo: Working or Discussion Paper Palavras-chave: Aggregation; Rank; Functional form; Integrability; Research Methods/ Statistical Methods; D12; E21.
Ano: 2005 URL: http://purl.umn.edu/25048
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Projecting World Food Demand: A Comparison of Alternative Demand Systems AgEcon
Yu, Wusheng; Hertel, Thomas W.; Preckel, Paul V.; Eales, James S..
Projections of world food demands hinge critically on the underlying functional form used to predict future demands. Simple functional forms can lead to unrealistic projections by failing to capture changes in income elasticities of demand as consumer becomes wealthier. This paper compares several demand systems in the projection of disaggregated food demand across a wide range of countries with different income levels using a global general equilibrium model. We find that the recently introduced AIDADS system represents a substantial improvement over existing demand systems currently in use in CGE modeling. In particular, our projection results show that for relatively poor regions experiencing rapid income growth, the widely used LES and CDE demand...
Tipo: Conference Paper or Presentation Palavras-chave: Food demand; Agricultural trade; Functional form; Demand system; CGE modeling; Demand and Price Analysis.
Ano: 2002 URL: http://purl.umn.edu/24877
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PROJECTING WORLD FOOD DEMAND USING ALTERNATIVE DEMAND SYSTEMS AgEcon
Yu, Wusheng; Hertel, Thomas W.; Preckel, Paul V.; Eales, James S..
Computable General Equilibrium (CGE) models are increasingly being used to project world food markets in order to support forward-looking policy analysis. Such projections hinge critically on the underlying functional form for representing consumer demand. Simple functional forms can lead to unrealistic projections by failing to capture changes in income elasticities of demand. We adopt as our benchmark the recently introduced AIDADS demand system and compare it with several alternaive demand systems currently in widespread use in CGE models. This comparison is conducted in the context of projections for disaggregated global food demand using a global CGE model. We find that AIDADS represents a substantial improvement, particularly for the rapidly...
Tipo: Conference Paper or Presentation Palavras-chave: Food demand; Agricultural trade; Functional form; Demand system; CGE modeling; Demand and Price Analysis; D12; C68; F17; Q18.
Ano: 2003 URL: http://purl.umn.edu/25905
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The Need for Theoretically Consistent Efficiency Frontiers AgEcon
Sauer, Johannes; Hockmann, Heinrich.
The availability of efficiency estimation software –freely distributed via the internet and relatively easy to use –recently inflated the number of corresponding applications. The resulting efficiency estimates are often used without a critical assessment with respect to the literature on theoretical consistency, flexibility and the choice of the appropriate functional form. The robustness of policy suggestions based on inferences from efficiency measures nevertheless crucially depends on theoretically well-founded estimates. This paper addresses stochastic efficiency measurement by critically reviewing the theoretical consistency of recently published technical efficiency estimates. The results confirm the need for a posteriori checking the regularity of...
Tipo: Conference Paper or Presentation Palavras-chave: Functional form; Stochastic efficiency analysis; Theoretical consistency; Research and Development/Tech Change/Emerging Technologies; C51; D24; Q12.
Ano: 2005 URL: http://purl.umn.edu/24497
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Una prueba sobre la especificación de un modelo de regresión. Colegio de Postgraduados
Pineda Norman, Amanda Lolita.
Un modelo de regresión lineal múltiple tiene problemas de especificación incorrecta de la forma funcional cuando no explica en forma adecuada la relación entre la variable dependiente y las explicativas observadas. Una prueba sobre la especificación del modelo es la prueba RESET; sin embargo, la prueba ha demostrado tener baja potencia, quedando además poco clara la forma de definir las variables que serán incluidas en la regresión auxiliar que utiliza, presentando por construcción problemas de multicolinealidad. En el presente trabajo se propone una prueba de especificación basada en Multiplicadores de Lagrange y la regresión Lasso Adaptativo (Zou2006) a la cual le llamamos ML-ALasso. Al igual que la prueba RESET, la prueba ML-ALasso se basa en una...
Palavras-chave: RESET; Lasso adaptativo; Multiplicador de Lagrange; Prueba de permutaciones; Error de especificación; Forma funcional; RESET test; Adaptive Lasso; Lagrange Multiplier; Permutation Test; Misspecification; Functional form; Estadística; Maestría.
Ano: 2013 URL: http://hdl.handle.net/10521/2178
Registros recuperados: 10
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