Previsão do preço dos principais grãos do Rio Grande do Sul

Abstract

This work deals with forecasts to the year of 2007 in relation to the main cultivations prices of temporary farming developed in Rio Grande do Sul state. The database for the definition of the main grains to be analyzed were selected through the annual average from 1995 to 2006 of the produced amount. The forecasts are referred to the grain prices from January 1995 to December 2006 in the ‘gaúcho’ state. This study is important since agriculture is likely to be receptive to new technologies in addition to resources that attribute aggregated values for products, turning the activity much more competitive. The viability of the activity, with satisfactory profit, is always in risk due to controllable and uncontrollable factors that define the farming production. Having knowledge about these forecasts, people who live in Rio Grande do Sul have tools in order to develop their planning through gain and benefit expectations, aggregating value to their work. To accomplish the forecasts in relation to prices of soybean, rice and sweetcorn in RS state, one did use of the Box & Jenkins methodology. To such cultivations, the methodoly showed many significant models, however, through the penalizing criterias, AIC e SBC, in addition the square average error, it was possible to choose the best model for each serie, being the model ARIMA (0,1,2)(0,1,0) to soybean; the model SARIMA (1,1,0)(1,0,1) to rice and the model ARIMA (2,1,1)(0,1,0) to sweetcorn.