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Analysis of Intended Farmers’ Response to CAP Scenarios: Environmental considerations AgEcon
Giannoccaro, Giacomo; Berbel, Julio.
This research is a result of the CAP-IRE project which objective is the understanding farmer’s reactions under CAP scenarios by 2020. In particular this research aims to analyze the role of the current CAP design on the farmer’s decision process focusing on several environmental issues. The analysis is based on 2,360 observations of household farmers across 11 cases study in 9 EU countries. Intended responses of farmers to the CAP reforms are analyzed by logistic model regression. According to the results CAP scenarios would influence farmer’s decision on fertilizers and pesticides, as well as water use, while the highest effect is found for decisions on number of animal rearing on the farm. Factors determining reaction to the CAP scenario are monetary and...
Tipo: Conference Paper or Presentation Palavras-chave: Environmental sustainability; Farmer’s intended behaviour; Logistic regression; Agricultural policy; Agricultural and Food Policy; Environmental Economics and Policy; Q18.
Ano: 2011 URL: http://purl.umn.edu/99419
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Áreas prioritarias mediante escenarios de deforestación y servicios ambientales en la Sierra Norte de Puebla. Colegio de Postgraduados
Chávez González, Honoria.
La identificación de áreas prioritarias es una herramienta valiosa que permite orientar y optimizar los esfuerzos de estudio, conservación y aprovechamiento sustentable de recursos forestales. La presente investigación integró una metodología, mediante la combinación de diferentes técnicas cuantitativas en un ambiente de sistemas de información geográfica y sensores remotos, para la identificación de áreas prioritarias de recarga hídrica en la Unidad de Manejo Forestal Zacatlán, Puebla. El estudio se constituyó de tres componentes de investigación: (1) Análisis retrospectivo (1986-2010), actual y perspectivo (2010-2030) de cambios de uso de la tierra y riesgo de deforestación; (2) Identificación de áreas con aptitud para proveer servicios ambientales...
Palavras-chave: Cambio de uso de la tierra; Riesgo de deforestación; Recarga de acuíferos; Evaluación multicriterio; Regresión logística; Land use change; Deforestation risk; Aquifer recharge; Multicriteria evaluation; Logistic regression; Forestal; Maestría.
Ano: 2014 URL: http://hdl.handle.net/10521/2248
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Áreas prioritarias para captura de carbono en los municipíos de Chignahuapan-Zacatlán, Puebla. Colegio de Postgraduados
Cruz Huerta, Carmina.
Las áreas prioritarias de conservación son una herramienta importante que permiten optimizar el aprovechamiento y conservación de los recursos naturales y forestales. La presente investigación tiene como objetivo definir las áreas prioritarias de conservación de captura de carbono mediante la combinación del riesgo de deforestación y aptitud de captura de carbono con la finalidad de generar estrategias de manejo y conservación. La metodología incluye sistemas de información geográfica y técnicas cuantitativas para determinar las áreas prioritarias de conservación de captura de carbono. La metodología incluyó: (1) Determinación del riesgo futuro de deforestación en dos escalas espaciales; y (2) Identificación de áreas prioritarias de conservación de captura...
Palavras-chave: Escalas espaciales; Riesgo de deforestación; Captura de carbono; Regresión logística; Spatial scales; Risk of deforestation; Carbon sequestration; Logistic regression; Forestal; Maestría.
Ano: 2014 URL: http://hdl.handle.net/10521/2282
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Attitudes of College Students towards Agriculture, Food and the Role of Government AgEcon
Carreira, Rita I.; Mane, R.; Danforth, Diana M.; Wailes, Eric J..
In 2002 and 2007 we surveyed Agribusiness students’ attitudes about agriculture, farming, food and agricultural policies. Responses were analyzed by year and student characteristics including farm background, citizenship and gender. Citizenship was a significant variable explaining differences in agreement with statements. Year and interactions with year were not significant.
Tipo: Conference Paper or Presentation Palavras-chave: Agricultural policy; Farming; Logistic regression; Student attitudes; Agricultural and Food Policy; Teaching/Communication/Extension/Profession; A13; A22; C42; Q18.
Ano: 2008 URL: http://purl.umn.edu/6806
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Bernoulli Regression Models: Re-examining Statistical Models with Binary Dependent Variables AgEcon
Bergtold, Jason S.; Spanos, Aris.
The classical approach for specifying statistical models with binary dependent variables in econometrics using latent variables or threshold models can leave the model misspecified, resulting in biased and inconsistent estimates as well as erroneous inferences. Furthermore, methods for trying to alleviate such problems, such as univariate generalized linear models, have not provided an adequate alternative for ensuring the statistical adequacy of such models. The purpose of this paper is to re-examine the underlying probabilistic foundations of statistical models with binary dependent variables using the probabilistic reduction approach to provide an alternative approach for model specification. This re-examination leads to the development of the Bernoulli...
Tipo: Conference Paper or Presentation Palavras-chave: Bernoulli Regression Model; Logistic regression; Generalized linear models; Discrete choice; Probabilistic reduction approach; Model specification; Research Methods/ Statistical Methods.
Ano: 2005 URL: http://purl.umn.edu/19282
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Choosing an appropriate real-life measure of effect size: the case of a continuous predictor and a binary outcome AgEcon
Conroy, Ronan M..
A case study of data on age and pregnancy is used to point up some morals for practicing data analysts, including the superiority of regression over t tests, exploratory scatterplot smoothing as a key method of checking form of relationship, and the value of logistic regression followed by adjust as a way of getting at the numbers of most interest.
Tipo: Journal Article Palavras-chave: Adjust; Correlation; Logistic regression; Regression; Scatterplot smoothing; T tests; Research Methods/ Statistical Methods.
Ano: 2002 URL: http://purl.umn.edu/116011
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Clinical and epidemiological characteristics associated with unfavorable tuberculosis treatment outcomes in TB-HIV co-infected patients in Brazil: a hierarchical polytomous analysis BJID
Prado,Thiago Nascimento do; Rajan,Jayant V.; Miranda,Angélica Espinosa; Dias,Elias dos Santos; Cosme,Lorrayne Beliqui; Possuelo,Lia Gonçalves; Sanchez,Mauro N.; Golub,Jonathan E.; Riley,Lee W.; Maciel,Ethel Leonor.
Abstract Background: TB patients co-infected with HIV have worse treatment outcomes than non-coinfected patients. How clinical characteristics of TB and socioeconomic characteristics influence these outcomes is poorly understood. Here, we use polytomous regression analysis to identify clinical and epidemiological characteristics associated with unfavorable treatment outcomes among TB-HIV co-infected patients in Brazil. Methods: TB-HIV cases reported in the Brazilian information system (SINAN) between January 1, 2001 and December 31, 2011 were identified and categorized by TB treatment outcome (cure, default, death, and development of MDR TB). We modeled treatment outcome as a function of clinical characteristics of TB and patient socioeconomic...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Tuberculosis; HIV; Coinfection; Logistic regression.
Ano: 2017 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1413-86702017000200162
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Consumer behaviour in the Hungarian beer market AgEcon
Hajdu, Istvanne; Major, Anita; Lakner, Zoltan.
In the Hungarian food economy beer marketing remains something of an enigma. Based on a direct-question survey, focussing mainly on educated younger consumers, this article offers an overview of the most important characteristics of Hungarian beer consumption. It is important to stress that beer consumption is situational, meaning tied to specific consumption situations. Research results prove that logistic regression analysis is a suitable method for determining why consumers opt for specific beverages in specific consumption situations. To analyse targeted marketing, the application of heuristic methods, and decision trees provide a high degree of accuracy. This has proven true for consumers that drink non-alcoholic beers.
Tipo: Journal Article Palavras-chave: Direct-question survey; Consumer study; Logistic regression; Decision tree approach; Consumer/Household Economics; Food Consumption/Nutrition/Food Safety.
Ano: 2007 URL: http://purl.umn.edu/47016
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Controlling for time-dependent confounding using marginal structural models AgEcon
Fewell, Zoe; Hernan, Miguel A.; Wolfe, Frederick; Tilling, Kate; Choi, Hyon; Sterne, Jonathan A.C..
Longitudinal studies in which exposures, confounders, and outcomes are measured repeatedly over time have the potential to allow causal inferences about the effects of exposure on outcome. There is particular interest in estimating the causal effects of medical treatments (or other interventions) in circumstances in which a randomized controlled trial is difficult or impossible. However, standard methods for estimating exposure effects in longitudinal studies are biased in the presence of time-dependent confounders affected by prior treatment. This article describes the use of marginal structural models (described by Robins, Hernán, and Brumback [2000]) to estimate exposure or treatment effects in the presence of time-dependent confounders affected by...
Tipo: Journal Article Palavras-chave: Marginal structural models; Causal models; Weighted regression; Survival analysis; Logistic regression; Confounding; Research Methods/ Statistical Methods.
Ano: 2004 URL: http://purl.umn.edu/116267
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Determinant factors in adopting socio-environmental certifications in coffee farms¹ Rev. Econ. Sociol. Rural
Silva,Eduardo Cesar; Castro Junior,Luiz Gonzaga; Costa,Cássio Henrique Garcia; Andrade,Fabrício Teixeira.
Certified coffee production is an opportunity for the grower to differ his product. However, the number of certified producers is still relatively small. In order to contribute to the dissemination of accreditation among farmers, the objective of this study is to identify the factors that determine its adoption, based on a sample of certified and non-certified growers from the south of Minas Gerais, Brazil. Quantitative data were analyzed through logistic regression. Results showed that five variables were significant in explaining the certification adoption: grower's age; role of coffee in family income; attending courses and events; computer use in the farm and crop yield. These results expand the existing knowledge about coffee certifications and can...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Logistic regression; Coffee growing; Resource based view.
Ano: 2014 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-20032014000300002
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DETERMINANTS OF AGRICULTURAL LAND ABANDONMENT IN POST-SOVIET EUROPEAN RUSSIA AgEcon
Prishchepov, Alexander V.; Radeloff, Volker C.; Muller, Daniel; Dubinin, Maxim; Baumann, Matthias.
Socio-economic and institutional changes may accelerate land-use and land-cover change. Our goal was to explore the determinants of agricultural land abandonment within one agro-climatic and economic region of post-Soviet European Russia during the first decade of transition from a state-command to market-driven economy (between 1990 and 2000). We integrated maps of abandoned agricultural land derived from 30 m resolution Landsat TM/ETM+ images, environmental and socioeconomic variables and estimated logistic regressions. Results showed that post-Soviet agricultural land abandonment was significantly associated with lower average grain yields in the late 1980s, higher distance from the populated places, areas with low population densities, for isolated...
Tipo: Conference Paper or Presentation Palavras-chave: Agricultural land abandonment; Institutional change; Land use change; Spatial analysis; Logistic regression; Remote sensing; Russia; Agribusiness; Q15.
Ano: 2011 URL: http://purl.umn.edu/115363
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Determinants of Credit Rationing for Corporate Farms in Russia AgEcon
Subbotin, Alexander.
The Russian establishment- politicians, agricultural officials, corporate farm managers, the media- firmly believe that inadequate access to credit is one of the major factors constraining the growth of the agricultural sector. In technical terms, they in effect claim that Russian agriculture faces credit rationing. In this article, we apply discrete regression analysis to study the determinants of access to credit for corporate farms, without addressing the issue of whether or not the actual borrowing is sufficient for the farms' needs. Our analysis shows that factors reflecting economic efficiency are the main determinants of access to credit. On the other hand, asset endowments, such as land and capital stock, have a very weak effect on the ability to...
Tipo: Conference Paper or Presentation Palavras-chave: Russian agriculture; Transition economics; Farm finance; Credit rationing; Logistic regression; Agricultural Finance; P340; Q140.
Ano: 2005 URL: http://purl.umn.edu/24514
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Factors associated with fecal-shedding of Salmonella spp by horses on US operations Arq. Bras. Med. Vet. Zootec.
Losinger,W.C.; Traub-Dargatz,J.L.; Garber,L.P.; Fedorka-Cray,P.J.; Ladely,S.; Ferris,K.E.; Morgan,K..
In a cross-sectional national study that included 972 operations with > 3 horses on 1/1/98 in 28 states in the USA, 8,417 fecal specimens were collected from horses and cultured to test for the presence of Salmonella spp. Operations were characterized as Salmonella spp-positive if at least one fecal specimen tested positive for Salmonella spp. Percentages of Salmonella spp-positive operations were computed by management and other factors (collected from operation-level questionnaires) that were hypothesized to be related to fecal shedding of Salmonella spp. A logistic-regression model was constructed to identify factors associated with horses’ shedding Salmonella spp in feces on an operation. The odds of an operation being Salmonella spp positive...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Equine operations; National survey; Risk factor analysis; Logistic regression.
Ano: 2002 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0102-09352002000200001
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Factors enhancing market participation by small-scale cotton farmers AgEcon
Randela, Rendani; Alemu, Zerihun Gudeta; Groenewald, Jan A..
This paper uses data collected from 177 small-scale farming households in Mpumalanga in an effort to identify factors that significantly influence the degree of commercialisation or market participation. A logistic regression model was applied within the transaction costs framework. Results support the hypothesis that transactions costs rank among the main determinants of commercialisation. The following variables were statistically significant: age, ability to speak/understand English, region, ownership of transport, access to market information, distance to market, dependency ratio, trust, land size and ownership of livestock. Increases in the latter four have negative effects on commercialisation. The negative relationship between land size and...
Tipo: Journal Article Palavras-chave: Market participation; Household commercialisation; Logistic regression; Transaction costs.
Ano: 2008 URL: http://purl.umn.edu/47656
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Generalized ordered logit/partial proportional odds models for ordinal dependent variables AgEcon
Williams, Richard A..
This article describes the gologit2 program for generalized ordered logit models. gologit2 is inspired by Vincent Fu’s gologit routine (Stata Technical Bulletin Reprints 8: 160–164) and is backward compatible with it but offers several additional powerful options. A major strength of gologit2 is that it can fit three special cases of the generalized model: the proportional odds/parallel-lines model, the partial proportional odds model, and the logistic regression model. Hence, gologit2 can fit models that are less restrictive than the parallel-lines models fitted by ologit (whose assumptions are often violated) but more parsimonious and interpretable than those fitted by a nonordinal method, such as multinomial logistic regression (i.e., mlogit). Other key...
Tipo: Journal Article Palavras-chave: Gologit2; Gologit; Logistic regression; Ordinal regression; Proportional odds; Partial proportional odds; Generalized ordered logit model; Parallel-lines model; Research Methods/ Statistical Methods.
Ano: 2006 URL: http://purl.umn.edu/117557
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Goodness-of-fit test for a logistic regression model fitted using survey sample data AgEcon
Archer, Kellie J.; Lemeshow, Stanley.
After a logistic regression model has been fitted, a global test of goodness of fit of the resulting model should be performed. A test that is commonly used to assess model fit is the Hosmer–Lemeshow test, which is available in Stata and most other statistical software programs. However, it is often of interest to fit a logistic regression model to sample survey data, such as data from the National Health Interview Survey or the National Health and Nutrition Examination Survey. Unfortunately, for such situations no goodness-of-fit testing procedures have been developed or implemented in available software. To address this problem, a Stata ado-command, svylogitgof, for estimating the F-adjusted mean residual test after svy: logit or svy: logistic estimation...
Tipo: Journal Article Palavras-chave: Svylogitgof; Goodness of fit; Survey design; Svy; Logistic regression; Logit; Research Methods/ Statistical Methods.
Ano: 2006 URL: http://purl.umn.edu/117559
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Graphical representation of interactions AgEcon
Barthel, Friederike Maria-Sophie; Royston, Patrick.
We provide a program to illustrate interactions between treatment and covariates or between two covariates by using forest plots under either the Cox proportional hazards or the logistic regression model. The program is flexible in both the possibility of illustrating more than one interaction at a time and variable specifications of scale.
Tipo: Journal Article Palavras-chave: Fintplot; Interaction; Forest plot; Randomized controlled trial; Survival analysis; Logistic regression; Research Methods/ Statistical Methods.
Ano: 2006 URL: http://purl.umn.edu/117585
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How can Farmer Managerial Capacity Contribute to Improved Farm Performance? A Study of Dairy Farms in Sweden AgEcon
Johansson, Helena.
This paper investigates how managerial capacity aspects influence efficiency of dairy farms in Sweden. Based on non-parametric methods, Tobit and logistic regressions, several managerial capacity aspects are found to influence long and short run input efficiency scores, but to influence output efficiency less. Examples of important aspects are: internal locus of control, positive profitability attitude, profitability perception and participation in study circles. Based on this, a way of supporting dairy farms to become more profitable is to organize educational and discussion clubs where the farmers learn from each other and form professional dairy farm advisors.
Tipo: Conference Paper or Presentation Palavras-chave: Dairy farms; Data envelopment analysis; Decision-making; Efficiency; Logistic regression; Managerial capacity; Tobit Regression; Farm Management; Productivity Analysis.
Ano: 2007 URL: http://purl.umn.edu/9874
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IMPACT OF ALTERNATIVE GRID PRICING STRUCTURES ON CATTLE MARKETING DECISIONS AgEcon
Greer, Heather C.; Trapp, James N..
Quality grade, yield grade, and other feedlot performance factors explain much of the variation in profit under grid pricing. Thus, feedlot owners can change profits by adjusting time on feed to influence these performance factors. This research uses growth models, logistic regression, and an optimization process to determine how the optimal number of days on feed changes under different grid pricing structures. It was found that large quality or small yield discounts increases the optimal number of days on feed and small quality or large yield discounts result in fewer days on feed. Losses associated with a grid having large quality discounts are minimized as cattle fed for more days are able to obtain Choice premiums despite the discounts for more Yield...
Tipo: Conference Paper or Presentation Palavras-chave: Grid pricing; Profits; Animal growth; Logistic regression; Days on feed; Livestock Production/Industries; Marketing.
Ano: 2000 URL: http://purl.umn.edu/18926
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La diversidad y prácticas de manejo de los animales domésticos en la región de la montaña del estado de Guerrero. Colegio de Postgraduados
López Gordillo, José Antonio.
Se analizó la diversidad de los animales domésticos presentes y las prácticas de manejo en la región de la Montaña del estado de Guerrero. En el estudio se realizaron 207 entrevistas a productores para registrar información de la familia, la ganadería, los recursos naturales utilizados y las prácticas de manejo. Los datos se analizaron con el paquete estadístico SAS. Se estimaron los estadísticos descriptivos para las variables de las explotaciones y los indicadores de la presencia de los animales domésticos. La función social y productiva de cada especie ganadera se determinó con regresión logística. La población promedio de animales en la explotación estuvo determinada por las aves (18.3), caprinos (14.8), bovinos (12.3), ovinos (9.4), cerdos (6) y...
Palavras-chave: Densidad de ganado; Indice de diversidad; Peso vivo; Regresión logística; Sanidad; Alimentación; Livestock density; Diversity index; Live weight; Logistic regression; Health management; Feeding practices; EDAR; Estrategias para el Desarrollo Agrícola Regional; Maestría Tecnológica; Desarrollo Sostenible de Zonas Indígenas.
Ano: 2010 URL: http://hdl.handle.net/10521/359
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