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Premium Estimation Inaccuracy and the Actuarial Performance of the US Crop Insurance Program AgEcon
Ramirez, Octavio A.; Carpio, Carlos E..
This article explores the impact of the likely levels of inaccuracy associated with two main types of premium estimation methods, under different sample sizes, on the actuarial performance of the US crop insurance program. The analyses are conducted under several plausible assumptions about the insurer versus the producers’ estimates for their actuarially fair premiums. Significant differences are found due to estimation method and sample size, with the currently used procedures resulting in the worse actuarial performance. Several conclusions and recommendations are provided that could markedly reduce the amount of public subsidies needed to keep this program solvent.
Tipo: Conference Paper or Presentation Palavras-chave: Agricultural Subsidies; Crop Insurance Premium Estimation; Loss-Cost Procedures; Risk Management Agency; Financial Economics.
Ano: 2011 URL: http://purl.umn.edu/102463
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Local Food Impacts on Health and Nutrition AgEcon
Ferrer, Myra Clarisse R.; Fonsah, Esendugue Greg; Ramirez, Octavio A.; Escalante, Cesar L..
Prevalence of local foods is believed to answer several food issues one of which is health and nutrition. This study focused on the on the availability of local foods to consumers and see its relationship with two specific diet-related diseases namely, obesity and diabetes. Other variables were included in the analysis to provide additional evidence to previous findings. Factors considered are divided into 5 groups namely diet-, local food-, environment-, education- and gender-related factors. Diet- and environment-related variables provide the most perceptive findings while local food variables provided significant however weak evidence of positive impacts to health and nutrition.
Tipo: Conference Paper or Presentation Palavras-chave: Local foods; Diabetes; Obesity; Food environment; Farmers' market; Agricultural and Food Policy; Consumer/Household Economics; Food Consumption/Nutrition/Food Safety; Health Economics and Policy; I15; I31.
Ano: 2011 URL: http://purl.umn.edu/103664
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Universidad Estatal de Nuevo Mexico NMSU. Campus las Cruces AgEcon
Ramirez, Octavio A..
The New Mexico State University, which is denominated as New Mexico's “Land Grant University”, is formed by more than 24,000 students within its five sites throughout the state of New Mexico. The main site, which is located in the bicultural city of Las Cruces, houses around 16,000 students, including 3,300 graduate ones distributed in 51 graduate degree programs and 25 Ph.D. programs. NMSU is classified by the Carnegie Foundation as a “Research Extensive” University. In terms of administration it is divided into six faculties, including the Agriculture and Domestic Economy Faculty (CAHE).
Tipo: Journal Article Palavras-chave: NMSU; Las Cruces; Graduate degree and Ph.D. programs; Agribusiness.
Ano: 2008 URL: http://purl.umn.edu/48613
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ASSESSING THE FINANCIAL RISKS OF DIVERSIFIED COFFEE PRODUCTION SYSTEMS: AN ALTERNATIVE NONNORMAL CDF ESTIMATION APPROACH AgEcon
Ramirez, Octavio A.; Sosa, Romeo.
Recently developed techniques are adapted and combined for the modeling and simulation of crop yields and prices that can be mutually correlated, exhibit heteroskedasticity or autocorrelation, and follow nonnormal probability density functions. The techniques are applied to the modeling and simulation of probability distribution functions for the returns of three tropical agroforestry systems for coffee production. The importance of using distribution functions that can more closely reflect the statistical behavior of yields and prices for risk analysis is discussed and illustrated.
Tipo: Journal Article Palavras-chave: Risk and Uncertainty.
Ano: 2000 URL: http://purl.umn.edu/30838
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The Asymmetric Cycling of U.S. Soybeans and Brazilian Coffee Prices: An Opportunity for Improved Forecasting and Understanding of Price Behavior AgEcon
Ramirez, Octavio A..
The behavior of agricultural commodity markets can arguably result in markedly asymmetric price cycles, that is, downward cycles of substantially different length and breadth than upward cycles. This study assesses whether asymmetric-cycle models can enhance the understanding of the dynamics and provide for a better forecasting of U.S. soybeans and Brazilian coffee prices. The forecasts from asymmetric cycle models are found to be substantially mode precise than those obtained from standard autoregressive models. The asymmetric cycle models also provide useful insights on the markedly different dynamics of the upward versus the downward cycles exhibited by the prices of these two commodities.
Tipo: Journal Article Palavras-chave: Asymmetric cycles; Coffee prices; Soybean prices; Threshold autoregressive models; Time series forecasting; Agribusiness; Crop Production/Industries; Demand and Price Analysis; Risk and Uncertainty; C22; C53.
Ano: 2009 URL: http://purl.umn.edu/48760
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ARE CROP YIELDS NORMALLY DISTRIBUTED? AgEcon
Ramirez, Octavio A.; Misra, Sukant K.; Field, James E..
This paper revisits the issue of crop yield distributions using improved model specifications, estimation and testing procedures that address the methodological concerns raised in recent literature that could have invalidated previous conclusions of yield non-normality. It shows beyond reasonable doubt that some crop yield distributions are non-normal, kurtotic and right or left skewed, depending on the circumstances. A procedure to jointly estimate non-normal farm- and aggregate-level yield distributions with similar means but different variances is illustrated, and the consequences of incorrectly assuming yield normality are explored.
Tipo: Conference Paper or Presentation Palavras-chave: Yield non-normality; Probability distribution function models; Corn Belt yields; West Texas dryland cotton yields; Crop Production/Industries.
Ano: 2001 URL: http://purl.umn.edu/20695
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Potential for Tradable Water Allocation and Rights in Jordan AgEcon
Carpio, Carlos E.; Ramirez, Octavio A.; Boonsaeng, Tullaya.
This paper estimates the costs of buying water use rights from farmers located in the Mafraq-Azraq basin in Jordan. Farmers’ water supply curve is estimated using data gathered from a contingent valuation survey. Estimation results indicate that a total supply of 29 million m3 could be periodically purchased from farmers at an annual price of approximately JD 0.23/m3 (1 JD ≈ 0.70 U.S. dollars), or a total cost of about JD 6.8 million per year.
Tipo: Conference Paper or Presentation Palavras-chave: Contingent valuation; Non-parametric estimation; Water supply curve; Research Methods/ Statistical Methods; Resource /Energy Economics and Policy.
Ano: 2010 URL: http://purl.umn.edu/56452
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AUTOREGRESSIVE CONDITIONAL HETEROSKEDASTICY UNDER ERROR-TERM NON-NORMALITY AgEcon
Ramirez, Octavio A..
This paper explores the impact of error-term non-normality on the performance of the normal-error Generalized Autoregressive Conditional Heteroskedastic (GARCH) model under small and moderate sample sizes. A non-normal-, asymmetric-error GARCH model is proposed, and its finite-sample performance is evaluated in comparison to the normal-error GARCH under various underlying error-term distributions. The results suggest that one must be skeptical of using the normal-error GARCH when there is evidence of conditional error-term non-normality. The conditional distribution of the error-term in a previous mainstream application of the normal GARCH is found to be non-normal and asymmetric. The same application is used to illustrate the advantages of the proposed...
Tipo: Conference Paper or Presentation Palavras-chave: Error- term non-normality; Skewness; Autoregressive conditional heteroskedasticity; Research Methods/ Statistical Methods.
Ano: 2001 URL: http://purl.umn.edu/20595
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Evaluating Crop and Revenue Insurance Products as Risk Management Tools for Texas Cotton Producers AgEcon
Field, James E.; Misra, Sukant K.; Ramirez, Octavio A..
This paper develops and illustrates the application of a procedure to evaluate and compare the cost effectiveness of alternative crop insurance products for cotton in terms of their effect on expected producer net returns and the variation of net returns. Farm unit-level cotton yields and state-level price distributions are estimated by a multivariate nonnormal parametric modeling procedure and used to simulate the net returns to alternative crop insurance products over a 10-year planning horizon. The ranking of alternative insurance products using third-degree stochastic dominance is presented for Texas cotton producers.
Tipo: Journal Article Palavras-chave: Cotton; Crop insurance; Multivariate nonnormal parametric modeling; Stochastic dominance; C5; Q1.
Ano: 2003 URL: http://purl.umn.edu/37314
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Improving Forecast Performance with Reduced Parameter, Large Order AR Models AgEcon
Ramirez, Octavio A.; Dorfman, Jeffrey H..
Tipo: Conference Paper or Presentation Palavras-chave: Time series; Modelling; Bayesian probability; Research Methods/ Statistical Methods.
Ano: 2010 URL: http://purl.umn.edu/60917
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UNIVERSIDAD ESTATAL DE NUEVO MEXICO NMSU. CAMPUS LAS CRUCES: PROGRAMAS DE POSGRADO EN ECONOMIA AGRICOLA Y AGRONEGOCIOS AgEcon
Ramirez, Octavio A..
The New Mexico State University, which is denominated as New Mexico's “Land Grant University”, is formed by more than 24,000 students within its five sites throughout the state of NewMexico. The main site, which is located in the bicultural city of Las Cruces, houses around 16,000 students, including 3,300 graduate ones distributed in 51 graduate degree programs and 25 Ph.D. programs. NMSUis classified by the Carnegie Foundation as a “Research Extensive” University. In terms of administration it is divided into six faculties, including the Agriculture and Domestic Economy Faculty (CAHE).
Tipo: Journal Article Palavras-chave: NMSU; Las Cruces; Graduate degree and Ph.D. programs; NMSU; Las Cruces; Programas de maestría y doctorado.; Teaching/Communication/Extension/Profession.
Ano: 2008 URL: http://purl.umn.edu/45840
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Issues and Strategies for Aggregate Supply Response Estimation for Policy Analyses AgEcon
Ramirez, Octavio A.; Mohanty, Samarendu; Carpio, Carlos E.; Denning, Megan.
We demonstrate the use of the small-sample econometrics principles and strategies to come up with reliable yield and acreage models for policy analyses. We focus on demonstrating the importance of proper representation of systematic and random components of the model for improving forecasting precision along with more reliable confidence intervals for the forecasts. A probability distribution function modeling approach, which has been shown to provide more reliable confidence intervals for the dependent variable forecasts than the standard models that assume error term normality, is used to estimate cotton supply response in the Southeastern United States.
Tipo: Journal Article Palavras-chave: Nonnormality; Probability distribution function; Supply response; Q11; Q18; C32.
Ano: 2004 URL: http://purl.umn.edu/43420
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An Empirically-Grounded Comparison of the Johnson System versus the Beta as Crop Yield Distribution Models AgEcon
Ramirez, Octavio A.; McDonald, Tanya U..
Previous research established that the expanded Johnson system can accommodate any theoretically possible mean-variance-skewness-kurtosis combination. Therefore, it has been hypothesized that this system can provide for a reasonably accurate modeling approximation of any probability distribution that might be encountered in practice. In order to test that hypothesis, this manuscript develops a more flexible expanded form of the Beta distribution which, in its original form, has been widely used to model and simulate crop yields for risk analysis. Empirically grounded evaluations suggest that the Johnson system can model a variety of typical yield data-generating processes that are based on the Beta distribution much more precisely than the Beta can model...
Tipo: Conference Paper or Presentation Palavras-chave: Crop Production/Industries.
Ano: 2007 URL: http://purl.umn.edu/9814
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Empirically Evaluating the Flexibility of the Johnson Family of Distributions: A Crop Insurance Application AgEcon
Lu, Yue; Ramirez, Octavio A.; Rejesus, Roderick M.; Knight, Thomas O.; Sherrick, Bruce J..
This article examines the flexibility of the Johnson system of distributions by assessing its per-formance in terms of modeling crop yields for the purpose of setting actuarially fair crop in-surance premiums. Using data from corn farms in Illinois coupled with Monte Carlo simula-tion procedures, we found that average crop insurance premiums computed on the basis of the Johnson system provide reasonably accurate estimates even when the data are normal or come from a non-normal distribution other than the Johnson system (i.e., a beta). These results sug-gest that there is potential for using the Johnson system to rate previously uninsured crops that do not have historical insurance performance data upon which to base premium calculations.
Tipo: Journal Article Palavras-chave: Crop insurance; Crop yield modeling; Johnson distribution; Premium rate setting; Risk and Uncertainty.
Ano: 2008 URL: http://purl.umn.edu/44740
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Conclusive Evidence on the Benefits of Temporal Disaggregation to Improve the Precision of Time Series Model Forecasts AgEcon
Ramirez, Octavio A..
Simulation methods are used to measure the expected differentials between the Mean Square Errors of the forecasts from models based on temporally disaggregated versus aggregated data. This allows for novel comparisons including long-order ARMA models, such as those expected with weekly data, under realistic conditions where the parameter values have to be estimated. The ambivalence of past empirical evidence on the benefits of disaggregation is addressed by analyzing four different economic time series for which relatively large sample sizes are available. Because of this, a sufficient number of predictions can be considered to obtain conclusive results from out-of-sample forecasting contests. The validity of the conventional method for inferring the order...
Tipo: Presentation Palavras-chave: Data Aggregation; Efficient Forecasting; Research Methods/ Statistical Methods.
Ano: 2012 URL: http://purl.umn.edu/123470
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ECONOMIC VALUE OF THE CARBON SINK SERVICES OF TROPICAL SECONDARY FORESTS AND ITS MANAGEMENT IMPLICATIONS AgEcon
Ramirez, Octavio A.; Carpio, Carlos E.; Ortiz, Rosalba; Finnegan, Brian.
This paper explores the economic feasibility secondary forest regeneration and conservation as an alternative to help address global warming. Detailed measurements of tropical secondary forests through time, in different ecological zones of Costa Rica, are used for estimating carbon storage models. The paper addresses key issues in the international discussion about cross- and within-country compensation for carbon storage services and illustrates a method to compute/predict their economic value through time under a variety of scenarios. The procedure is applicable to other developing countries where secondary forest growth is increasingly important.
Tipo: Conference Paper or Presentation Palavras-chave: Tropical Forests; Carbon Sequestration; Global Warming; Activities Implemented Jointly.; Environmental Economics and Policy; Resource /Energy Economics and Policy; Q23; Q25; Q28..
Ano: 2000 URL: http://purl.umn.edu/21776
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Income Earning Potential versus Consumptive Amenities in Determining Ranchland Values AgEcon
Torell, L. Allen; Rimbey, Neil R.; Ramirez, Octavio A.; McCollum, Daniel W..
The relative importance of income earning potential versus consumptive values in setting ranchland prices is examined using a truncated hedonic model. The market value of New Mexico ranches is related to annual income earning potential and other ranch characteristics including ranch size, location, elevation, terrain, and the amount of deeded, public, and state trust land on the ranch. We found ranch income to be a statistically important determinant of land value, but yet a relatively small percentage of ranch value was explained by income earnings. Ranch location, scenic view, and the desirable lifestyle influenced ranch value more than ranch income.
Tipo: Journal Article Palavras-chave: Consumptive value; Grazing fees; Grazing permit value; Hedonic model; Land value; Lifestyle agriculture; Public land grazing; Voluntary grazing permit buyout; Land Economics/Use.
Ano: 2005 URL: http://purl.umn.edu/30986
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HIGH PRICE VOLATILITY AND SPILLOVER EFFECTS IN ENERGY MARKETS AgEcon
Singh, Aaron; Karali, Berna; Ramirez, Octavio A..
Replaced with revised version of paper 07/22/11.
Tipo: Conference Paper or Presentation Palavras-chave: Asymmetric shocks; Energy markets; Oil; Spillover effects; Volatility; Marketing; Resource /Energy Economics and Policy; GARCH.
Ano: 2011 URL: http://purl.umn.edu/103593
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JOINT MODELING AND SIMULATION OF AUTOCORRELATED NON-NORMAL TIME SERIES: AN APPLICATION TO RISK AND RETURN ANALYSIS AgEcon
Ramirez, Octavio A.; Somarriba, Eduardo.
This study presents a technique that can jointly model and simulate the expected values, variances, and covariances of sets of correlated time-series dependent variables that are autocorrelated and non-normal (right or left skewed and/or kurtotic). It illustrates the method by applying it to risk analysis of diversified tropical agroforestry systems.
Tipo: Conference Paper or Presentation Palavras-chave: Resource /Energy Economics and Policy; Risk and Uncertainty.
Ano: 1999 URL: http://purl.umn.edu/21564
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RISK AND RETURNS OF DIVERSIFIED CROPPING SYSTEMS UNDER NONNORMAL, CROSS-, AND AUTOCORRELATED COMMODITY PRICE STRUCTURES AgEcon
Ramirez, Octavio A.; Somarriba, Eduardo.
This study analyzes the risks of diversified tropical cropping systems that combine cocoa, plantain, and tree-crop components in different proportions versus traditional monocultures. A technique for modeling the expected values, variances, and covariances of correlated time-series variables that are autocorrelated and nonnormal (right or left skewed and kurtotic) is applied to simulate commodity prices. The importance of using simulated cumulative density functions (cdf's) which reflect the most important characteristics of the stochastic behavior of prices for analyzing risk and returns of diversified agricultural systems is demonstrated. The analysis priovides evidence in favor of diversified cocoa-plantain-Cordia agroforestry system technologies...
Tipo: Journal Article Palavras-chave: Demand and Price Analysis.
Ano: 2000 URL: http://purl.umn.edu/30901
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