AD Model Builder is unquestionably the fastest model parameter estimation software available in a commericial package. Our preliminary results with one model fitted and solved for estimates of the parameters in a few seconds. The same model requires about 20 minutes with the minimization routine in Mathematica. The power of the notation, designed specifically for model parameter estimation, allows code which requires many fewer lines to execute and decode than most (or in our experience, certainly, all) other programming languages.
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