CONSIDERATION OF TRENDS IN THE OPTIMIZATION OF FARM SYSTEMS UNDER RISK CONDITIONS
Benedito Silva Neto, Valter Jose Stulp
Abstract
The goal of this study was to develop a mathematical programming model which allowed the optimization of production systems in regard to trends in the results of economic activity, with consideration to contingent variations. The formulation of this model is based on the optimization of inter-annual deviations in the historical series of the results of economic activity. Numerical simulations of this model were compared to solutions obtained from the minimization of variance and the minimization of absolute deviation models. Both models were tested with and without the use of linear regressions. The obtained results reveal that the optimized model of inter-annual deviation selected activities by the trends in their economic results, increasing the level of activities with expanding results and decreasing the levels of activities with diminishing results in their solutions. The application of linear regression to the minimization of variance and minimization of absolute deviation models has not enabled these deviations to distinguish trends in the results. In the absence of positive or negative tendencies in the historical series, the optimization model of inter-annual trends revealed a superior capacity to reduce the variance than the minimization of the absolute deviation model.
Keywords
References
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