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	Provedor de dados AgEcon (4) Autor Wood, Stanley (3) You, Liangzhi (3) Wood-Sichra, Ulrike (2) El-Said, Moataz (1) Robinson, Sherman (1) Palavra-chave Cross entropy (4) Crop Production/Industries (3) Spatial allocation (3) Agricultural production (2) Crop suitability (2) Entropy (2) Q15 (2) Q24 (2) Satellite image (2) C6 (1) C60 (1) Crop distribution (1) GAMS (1) Global (1) Production (1) Remote sensing (1) Research Methods/ Statistical Methods (1) SAM (1) Social accounting matrices (1) Sub-Sahara Africa (1) Mais... Tipo do documento Conference Paper or Presentation (2) Working or Discussion Paper (2) Ano 2006 (1) 2004 (2) 2000 (1) País United States (4) Idioma Inglês (4)		Ordenar por:  Relevância Autor Título Ano Registros recuperados: 4 Primeira ... 1 ... Última Generating Global Crop Distribution Maps: From Census to Grid AgEcon You, Liangzhi; Wood, Stanley; Wood-Sichra, Ulrike. In order to evaluate food security, technology potential and the environmental impacts of production in a strategic and regional context, it is critical to have reliable information on the spatial distribution and coincidence of people, agricultural production, and environmental services. This paper proposes a spatial allocation model for generating highly disaggregated, crop-specific production data by a triangulation of any and all relevant background and partial information. This includes national or sub-national crop production statistics, satellite data on land cover, maps of irrigated areas, biophysical crop suitability assessments, population density, secondary data on irrigation and rainfed production systems, cropping intensity, and crop prices.... Tipo: Conference Paper or Presentation Palavras-chave: Global; Cross entropy; Satellite image; Spatial allocation; Agricultural production; Crop suitability; Crop Production/Industries; C6; Q15; Q24. Ano: 2006 URL: http://purl.umn.edu/25737 GENERATING PLAUSIBLE CROP DISTRIBUTION MAPS FOR SUB-SAHARA AFRICA USING SPATIAL ALLOCATION MODEL AgEcon You, Liangzhi; Wood, Stanley; Wood-Sichra, Ulrike. Spatial data, which are data that include the coordinates (either by latitude/longitude or by other addressing methods) on the surface of the earth, are essential for agricultural development. As fundamental parameters for agriculture policy research agricultural production statistics by geopolitical units such as country or sub-national entities have been used in many econometric analyses. However, collecting sub-national data is quite difficult in particular for developing countries. Even with great effort and only on regional scales, enormous data gaps exist and are unlikely to be filled. On the other hand, the spatial scale of even the subnational unit is relatively large for detailed spatial analysis. To fill these spatial data gaps we proposed a... Tipo: Conference Paper or Presentation Palavras-chave: Sub-Sahara Africa; Cross entropy; Satellite image; Spatial allocation; Agricultural production; Crop suitability; Crop Production/Industries; C60; Q15; Q24. Ano: 2004 URL: http://purl.umn.edu/19965 GAMS CODE FOR ESTIMATING A SOCIAL ACCOUNTING MATRIX (SAM) USING CROSS ENTROPY (CE) METHODS AgEcon Robinson, Sherman; El-Said, Moataz. This paper documents the computer code implementing the CE-SAM estimation technique in GAMS (General Algebraic Modeling System). It defines the estimation problem in a deterministic setting; extends the approach to include a stochastic treatment of errors in control totals; summarizes the equations describing CE technique for estimating a consistent SAM starting from an inconsistent data set estimated with error; and provides the GAMS code. Tipo: Working or Discussion Paper Palavras-chave: Entropy; Cross entropy; Social accounting matrices; SAM; GAMS; Research Methods/ Statistical Methods. Ano: 2000 URL: http://purl.umn.edu/16293 ASSESSING THE SPATIAL DISTRIBUTION OF CROP PRODUCTION USING A GENERALIZED CROSS-ENTROPY APPROACH AgEcon You, Liangzhi; Wood, Stanley. While agricultural production statistics are reported on a geopolitical – often national - basis we often need to know the status of production or productivity within specific sub-regions, watersheds, or agro-ecological zones. Such re-aggregations are typically made using expert judgments or simple area-weighting rules. We describe a new, entropy-based approach to making spatially disaggregated assessments of the distribution of crop production. Using this approach tabular crop production statistics are blended judiciously with an array of other secondary data to assess the production of specific crops within individual ‘pixels’ – typically 25 to 100 square kilometers in size. The information utilized includes crop production statistics, farming system... Tipo: Working or Discussion Paper Palavras-chave: Entropy; Cross entropy; Remote sensing; Spatial allocation; Production; Crop distribution; Crop Production/Industries. Ano: 2004 URL: http://purl.umn.edu/60324 Registros recuperados: 4 Primeira ... 1 ... Última

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