1. A method comprising: using a processor to generate a distortion adjustment model merit of accuracy by determining a difference between a signal input to the model and a signal output from the model, wherein the distortion adjustment model is used by a pre-distortion facility for distortion adjusting a radio frequency signal; optimizing a portion of the model based on the merit of accuracy; and using the processor to calculate a merit of accuracy of a candidate distortion adjustment model and updating the distortion adjustment model based on a comparison of the merit of accuracy of the candidate distortion adjustment model with the merit of accuracy of the distortion adjustment model.