SABIIA - Sistema Aberto e Integrado de Informação em Agricultura (Sabiia)

Pujula, Aude Liliana; Maradiaga, David Isaias; Dicks, Michael R..

In the research area of crop yield density estimation and in particular in risk analysis, little emphasis has been given to the appropriateness of transformation methods (e.g., removing a linear trend) and how such transformations impact the reliability of the empirical distribution functions and the resulting probability estimates. Similarly, there is little consensus on the impact of environmental variables (e.g., rainfall and temperature) on empirical distributions of yields. Using historical county corn yield data for Arkansas and Louisiana and nonparametric methods, this empirical analysis shed light on the importance of data transformation in crop risk analysis. Results demonstrate that inappropriate data treatment can lead to misestimation of...

Technology Adoption And Pest Control Strategies Among UK Cereal Farmers: Evidence from Parametric and Nonparametric Count Data Models

Palavras-chave: Probability Density Estimation; Nonparametric; Kernel; Nonstationary; Unit Roots; Data Transformations; Corn Yields; Weather; Production Economics; Research Methods/ Statistical Methods; Risk and Uncertainty.

Ano: 2010

URL: http://purl.umn.edu/56527

Sharma, Abhijit; Bailey, Alastair; Fraser, Iain.

This paper examines technology adoption and integrated pest management strategies employed by UK farmers, using both parametric and nonparametric methods. We employ a unique survey data set collected from UK cereal farmers to assess the determinants of technology adoption in relation to pest management. Our preferred model specification is nonparametric which makes use of the recently developed methods of Li and Racine (2007) and Racine and Li (2004). These methods allow us to combine categorical and continuous data and thereby avoid sample splitting and resulting efficiency losses. Our analysis reveals that total area farmed is positively related to the number of technologies adopted, whereas age is negatively related. We also find evidence of...

NONSTRUCTURAL AND STATISTICAL NONPARAMETRIC MARKET POWER TESTS: AN EMPIRICAL INVESTIGATION

Palavras-chave: Technology; Adoption; Cereal farming; UK; Nonparametric; Environmental Economics and Policy; Industrial Organization; Land Economics/Use; Risk and Uncertainty; O14; Q16.

Ano: 2009

URL: http://purl.umn.edu/51335

Noelke, Corinna M.; Raper, Kellie Curry.

We use Monte Carlo experiments to assess the accuracy of two nonstructural and two statistical nonparametric market power tests. We implement these monopoly and monopsony market power tests using data from ten known market structures. The objective is to determine which test is most able to distinguish between market structures. The statistical nonparametric market power tests appear to be promising.

Methodological innovations in estimating the (inverse) relationship between farm productivity and farm size in a developing economy: a case study of Burundi

Palavras-chave: Market power; Monte Carlo; Nonparametric; Nonstructural; Industrial Organization; Research Methods/ Statistical Methods.

Ano: 1999

URL: http://purl.umn.edu/21645

Verschelde, Marijn; Vandamme, Ellen; D'Haese, Marijke F.C.; Rayp, Glenn.

We use a nonparametric estimation of the production function to investigate the relationship between farm productivity and farming scale in poor smallholder agricultural systems in the north of Burundi. Burundi is one of the poorest countries in the world, with a predominant small scale subsistence farming sector. A Kernel regression is used on data of mixed cropping systems to study the determinants of production including different factors that have been identified in literature as missing variables in the testing of the inverse relationship such as soil quality, location and household heterogeneity. Household data on farm activities and crop production was gathered among 640 households in 2007 in two Northern provinces of Burundi. Four production models...

Challenging Small-scale Farming, A Non-parametric Analysis of the (Inverse) Relationship Between Farm Productivity and Farm Size in Burundi

Palavras-chave: Inverse relationship; Farm size; Nonparametric; Burundi; Agricultural and Food Policy; Community/Rural/Urban Development; Environmental Economics and Policy; D24; O13; Q12; Q18.

Ano: 2011

URL: http://purl.umn.edu/99359

Verschelde, Marijn; D'Haese, Marijke F.C.; Vandamme, Ellen; Rayp, Glenn.

We use a nonparametric estimation of the production function to investigate the relation- ship between farm productivity and farming scale in poor smallholder agricultural systems in the north of Burundi. Burundi is one of the poorest countries in the world, with a predominant small scale subsistence farming sector. A Kernel regression is used on data of mixed cropping systems to study the determinants of production including different factors that have been identified in literature as missing variables in the testing of the inverse relationship such as soil quality, location and household heterogeneity. Household data on farm activities and crop production was gathered among 640 households in 2007 in two Northern provinces of Burundi. Four production...

Analyzing Producer Preferences for Counter-Cyclical Government Payments

Palavras-chave: Inverse relationship; Farm size; Nonparametric; Burundi; Farm Management; Productivity Analysis.

Ano: 2011

URL: http://purl.umn.edu/115550

Miller, J. Corey; Barnett, Barry J.; Coble, Keith H..

A dynamic-stochastic model is developed to evaluate preferences among alternative countercyclical payment programs for representative farms producing corn or soybeans in Iowa and cotton or soybeans in Mississippi. Countercyclical payment programs are found to not necessarily be preferred to fixed payment programs.

Tipo: Journal Article

Palavras-chave: Agricultural policy; Bootstrapping; Countercyclical payments; Nonparametric; C15; D81; Q12; Q18.

Ano: 2003

URL: http://purl.umn.edu/43203

Estimating the Costs of Revenue Deficiency Programs

Cooper, Joseph C..

This paper develops an approach to empirically demonstrate how the within-season distribution of U.S. domestic commodity support for corn differs between current-style approaches of support and revenue-based support. From a purely economic standpoint, the results show the revenue-based payment scenarios to be preferable at the national level to the uncoordinated forms of support currently in use, even in a situation where the annual mean payments are set equal across the support scenarios. For revenue-based support, the variability around the total expected annual payment is lower, and perhaps more importantly, the probability of high payments is lower. These results suggest advantages to this type of support, both in terms of lower budgetary uncertainty ...

THE ROLE OF NON-PARAMETRIC APPROACH IN ADJUSTING PRODUCTIVITY MEASURES FOR ENVIRONMENTAL IMPACTS

Palavras-chave: Domestic support; Marketing loan benefits; Counter-cyclical payments; Disaster assistance; Revenue support; Corn; Nonparametric; Semi-nonparametric; Bootstrap; Financial Economics.

Ano: 2007

URL: http://purl.umn.edu/9699

Shaik, Saleem; Perrin, Richard K..

This paper addresses the role of non-parametric analysis in adjusting agricultural productivity measures for environmental impacts. The modified Tornquist-Theil index computed using shadow prices derived from the programming procedures is compared and contrasted with a non-parametric hyperbolic graph productivity index for the case of Nebraska agriculture.

Confidence intervals for rank statistics: Percentile slopes, differences, and ratios

Palavras-chave: Nonparametric; Shadow price; Productivity; Environmental Economics and Policy; Productivity Analysis.

Ano: 1999

URL: http://purl.umn.edu/21716

Impact of Income on Calorie and Nutrient Intakes: A Cross-Country Analysis

Newson, Roger.

I present a program, censlope, for calculating confidence intervals for generalized Theil–Sen median (and other percentile) slopes (and per-unit ratios) of Y with respect to X. The confidence intervals are robust to the possibility that the conditional population distributions of Y , given different values of X, differ in ways other than location, such as having unequal variances. censlope uses the program somersd and is part of the somersd package. censlope can therefore estimate confounder-adjusted percentile slopes, limited to comparisons within strata defined by values of confounders, or by values of a propensity score representing multiple confounders. Iterative numerical methods have been implemented in the Mata language, enabling efficient...

Tipo: Article

Palavras-chave: Somersd; Censlope; ALSPAC; Robust; Confidence interval; Rank; Nonparametric; Median; Percentile; Slope; Difference; Ratio; Kendall's τ; Somers' D; Theil–Sen; Hodges–Lehmann; Confounder adjusted; Propensity score; Research Methods/ Statistical Methods.

Ano: 2006

URL: http://purl.umn.edu/119241

Salois, Matthew J.; Tiffin, J. Richard; Balcombe, Kelvin George.

The relationship between income and nutrient intake is explored. Nonparametric, panel, and quantile regressions are used. Engle curves for calories, fat, and protein are approximately linear in logs with carbohydrate intakes exhibiting diminishing elasticities as incomes increase. Elasticities range from 0.10 to 0.25, with fat having the highest elasticities. Countries in higher quantiles have lower elasticities than those in lower quantiles. Results predict significant cumulative increases in calorie consumption which are increasingly composed of fats. Though policies aimed at poverty alleviation and economic growth may assuage hunger and malnutrition, they may also exacerbate problems associated with obesity.

TESTING FOR MONOPSONY POWER IN MULTIPLE INPUT MARKETS: A NONPARAMETRIC APPROACH WITH APPLICATION TO CIGARETTE MANUFACTURING

Palavras-chave: Calorie and nutrient consumption; Food and nutrition policy; Income elasticities; Nonparametric; Panel; Quantile regression.; Agricultural and Food Policy; Food Consumption/Nutrition/Food Safety; Food Security and Poverty; International Development; Research Methods/ Statistical Methods; C11; C14; C21; C23; O10; O47; Q18.

Ano: 2011

URL: http://purl.umn.edu/103647

Raper, Kellie Curry; Love, H. Alan.

Monopsony power by cigarette manufacturers in procuring domestic and imported tobacco is investigated using a nonparametric method previously developed by Love and Shumway. Their test is extended to assess monopsony market power in multiple input markets. Results indicate that cigarette manufacturers exert significant monopsony power in the domestic tobacco market and exert little monopsony power in the international tobacco market.

DISTINGUISHING THE SOURCE OF MARKET POWER: AN APPLICATION TO CIGARETTE MANUFACTURING

Palavras-chave: Market power; Tobacco; Nonparametric; Monopsony.; Agribusiness; L1..

Ano: 1998

URL: http://purl.umn.edu/23966

Raper, Kellie Curry; Love, H. Alan; Shumway, C. Richard.

We compare nonparametric and nonstructural market power tests using data from the cigarette manufacturing industry. Tests are implemented to examine both monopoly and monopsony power exertion by cigarette manufacturers. Results indicate that market power in the tobacco industry, previously attributed to monopoly power exertion, should at least in part be attributed to monopsony market power in the upstream tobacco market.

Superior Forecasts of the U.S. Unemployment Rate Using a Nonparametric Method

Palavras-chave: Market power; Nonparametric; Nonstructural; Monopsony; Monopoly; Cigarette manufacturing; Agribusiness.

Ano: 1998

URL: http://purl.umn.edu/24021

Golan, Amos; Perloff, Jeffrey M..

We use a nonlinear, nonparametric method to forecast the unemployment rates. We compare these forecasts to several linear and nonlinear parametric methods based on the work of Montgomery et al. (1998) and Carruth et al. (1998). Our main result is that, due to the nonlinearity in the data generating process, the nonparametric method outperforms many other wellknown models, even when these models use more information. This result holds for forecasts based on quarterly and on monthly data.

MONOPSONY POWER IN MULTIPLE INPUT MARKETS: A Nonparametric Approach

Palavras-chave: Embedding dimension; Nonlinearity; Nonparametric; Unemployment rate; Labor and Human Capital.

Ano: 2002

URL: http://purl.umn.edu/25060

Raper, Kellie Curry; Love, H. Alan.

Cigarette manufacturers' monopsony power exertion in procuring domestic and imported tobacco is investigated using nonparametric methods. While it is often assumed that tobacco program rents are captured by growers, results indicate the opposite actually occurs. Cigarette manufacturers appear to exert significant monopsony power in the domestic leaf tobacco market and capture a large portion of program rents. Cigarette manufacturers appear to exert monopsony power of much smaller magnitude in the international leaf tobacco market, but with increasing magnitude in more recent years.