However, unlike the model fit to xylose alone, the best fit of the model when all oligomer profiles are used in the fitting criteria does not correlate well (Φ=1,182) with any of the experimental profiles.
where f QLCP ( T, δ ) is the transformation fitting criterion described in Section 4.4 and ν is a positive constant.
In addition none of the other fitting criteria were met, indicating that a 3-factor model fitted the data better than either a 2-factor or a 1-factor model.
We applied the same fitting criteria (for convergence, positive definite Hessian and starting values) in all evaluations without consideration of whether they were uniformly applicable to all datasets.
This was achieved by introducing additional fitting criteria in the minimisation functional, which constrain the fitted surface in the regions with insufficient number of data points.
We thus argue that a more faithful implementation of graphical Granger modeling methods should take into account the group structure imposed by the time series into the modeling approach and fitting criteria that are used in the variable selection process.
Then, a comparison of the estimated models was performed by means of the mean square error and data fitting criteria in order to select the model that best describes the dynamic behaviour of the extrusion process.
A fitting threshold named confidence interval of fitting error is proposed to strike the balance between fitting accuracy and surface smoothness in the fitting process.
Both Y∞ and Y0 were floated in the fitting process.
In the fitting, k was treated as a global parameter.
