


Registros recuperados: 10  


Mandal, Maitreyi; Lagerkvist, Carl Johan. 
MeanVariance theory of portfolio construction is still regarded as the main building block of modern portfolio theory. However, many authors have suggested that the meanvariance criterion, conceived by Markowitz (1952), is not optimal for asset allocation, because the investor expected utility function is better proxied by a function that uses higher moments and because returns are distributed in a nonNormal way, being asymmetric and/or leptokurtic, so the meanvariance criterion cannot correctly proxy the expected utility with nonNormal returns. Copulas are a very useful tool to deal with non standard multivariate distribution. Value at Risk (VaR) and Conditional Value at Risk (CVaR) have emerged as a golden measure of risk in recent times. Though... 
Tipo: Presentation 
Palavraschave: Portfolio Choice; Downside Risk Protection; Value at risk; Copula; Agricultural Finance; Risk and Uncertainty; C52; G11; Q14. 
Ano: 2012 
URL: http://purl.umn.edu/124387 
 


Bokusheva, Raushan; Conradt, Sarah. 
The study evaluates the effectiveness of a catastrophic droughtindex insurance developed by applying two alternative methods  the standard regression analysis and the copula approach. Most empirical analyses obtain estimates of the dependence of crop yields on weather by employing linear regression. By doing so, they assume that the sensitivity of yields to weather remains constant over the whole distribution of the weather variable and can be captured by the effect of the weather index on the yield conditional mean. In our study we evaluate, whether the prediction of farm yield losses can be done more accurately by conditioning yields on extreme realisations of a weather index. Therefore, we model the dependence structure between yields and weather by... 
Tipo: Presentation 
Palavraschave: Catastrophic insurance; Weatherbased insurance; Copula; Risk and Uncertainty; C18; Q14. 
Ano: 2012 
URL: http://purl.umn.edu/122443 
 


Larsen, Ryan A.; Vedenov, Dmitry V.; Leatham, David J.. 
As agriculture becomes more industrialized, the role of risk measures such as valueatrisk (VaR) will become more utilized. In this case it was applied to geographical diversification and also modifying the traditional VaR estimation by incorporating a copula dependence parameter into the VaR estimation. In addition, an alternative risk measure was also calculated, CVaR. The CVaR, unlike VaR, is a coherent risk measure. Thus it does not suffer from many of the shortcomings of the VaR. The land portfolio consisted of Dryland wheat production acres in Texas, Colorado, and Montana. Three series of net returns were calculated for each region. Based on the VaR and the CVaR, the portfolio was optimized based on minimizing the expected loss based on... 
Tipo: Conference Paper or Presentation 
Palavraschave: Copula; CVaR; RiskManagement; Geographical Diversification; Agribusiness; Farm Management; Risk and Uncertainty. 
Ano: 2009 
URL: http://purl.umn.edu/46763 
 

 


Zhu, Ying; Ghosh, Sujit K.; Goodwin, Barry K.. 
The objective of this study is to evaluate and model the risks of corn and soybean production. This study focuses on the risk of revenue variability that arises from changes in prices, yields shortfalls or both. There are several models for price and yield risk factors for corn and soybeans. For instance, yield risks can be modeled by a family of Beta distributions, whereas price shocks can be modeled by lognormal distributions. In order to develop a multivariate model that preserves a given set of marginals, a copula approach can be used to characterize the joint yield and price risk of corn and soybeans, which are usually highly correlated. The copula approach has been spurred by the recent developments in the whole farm insurance (WFI), resulting in... 
Tipo: Conference Paper or Presentation 
Palavraschave: Copula; Crop Insurance; Loss Distribution; Farm Management. 
Ano: 2008 
URL: http://purl.umn.edu/6282 
 


SchulteGeers, Matthias; Berg, Ernst. 
The optimisation of production plans is an important topic in agriculture, often related to diversification and specialisation as the classical instruments of coping with production risk. Although the measurement of embedded risk is often inaccurate, it is nevertheless necessary for decision making to describe the common behaviour of different variables in a model. Imprecisely defined relationships influence the “right” choice, why it is important to find a good approximation of the real circumstances. In financial science, copula functions are frequently used instead of correlation coefficients to model joint price behaviour, because of the possibility to link the marginal distributions on multifarious ways. By now, agricultural science makes less use of... 
Tipo: Conference Paper or Presentation 
Palavraschave: Copula; Risk; Weather derivatives; Risk and Uncertainty. 
Ano: 2011 
URL: http://purl.umn.edu/115996 
 


Xu, Wei; Filler, Gunther; Odening, Martin; Okhrin, Ostap. 
Systemic weather risk is a major obstacle for the formation of private (nonsubsidized) crop insurance. This paper explores the possibility of spatial diversification of insurance by estimating the joint occurrence of unfavorable weather conditions in different locations. For that purpose copula methods are employed that allow an adequate description of stochastic dependencies between multivariate random variables. The estimation procedure is applied to weather data in Germany. Our results indicate that indemnity payments based on temperature as well as on cumulative rainfall show strong stochastic dependence even at a national scale. Thus the possibility to reduce risk exposure by increasing the trading area of the insurance is limited. Irrespective of... 
Tipo: Conference Paper or Presentation 
Palavraschave: Weather risk; Crop insurance; Copula; Risk and Uncertainty; C14; Q19. 
Ano: 2009 
URL: http://purl.umn.edu/49131 
 

 

 
Registros recuperados: 10  


