Comparison Between Linear and Non-Linear Regression Models in the Prediction of the Height of Gall Oak Trees (Quercus infectoria Olive.) in Duhok Governorate

Abstract This study was conducted for two main purposes, the first one to mathematical relationship between naturally growing gall oak trees in three microsites (Chamankey, Swaratoka, and Baroshky) Dohuk Governorate second compare ability of linear nonlinear regression models height estimation. For such a sample 152 purposely selected from these way that they cover whole variation breast diameter microsites. The STATGRAPHIC Centurion along with other computer facilities including Excel were used estimating parameters 32 all together. Many criteria testing performance developed equations prediction order select most appropriate model Screening generated performed stages; is use analysis see if have biological limitations. stage homogeneous models,(models same form dependent variable) variable. last dealt heterogeneous models, (models different forms