Adjusting the Clutter model using the Gretl software
Abstract
Growth and yield models are essential tools in the planning of forestry companies, in which the Clutter model one of the most used in Brazil. The aim was to demonstrate the necessary steps for the adjustment of the Clutter model by two-stage least square method, using the Gretl software. For this, we employed data from permanent plots in clonal eucalyptus stands, with age from 27 to 78 months. The form of organization of the database and the steps for their import into the software were specified in detail. The required variables to fit the model and the disposition of equation system were also explained. Finally, were commented on the results and their interpretation. The Gretl software represents an effective alternative on adjustment of Clutter model, especially for ease handling and because it has no costs.Downloads
References
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