Dear Subscribers, I did fit an equation of the form 1 = f(x1,x2,x3) using a minimization scheme. Now I want to compute the coefficient of determination. Normally I would compute it as
r_square = 1- sserr/sstot with sserr = sum_i (y_i - f_i) and sstot = sum_i (y_i - mean(y)) sserr is clear to me but how can I compute sstot when there is no such thing than differing y_i. These are all one. Thus mean(y)=1. Therefore, sstot is 0. Thank you very much for your efforts, Uwe -- Uwe Wolfram Dipl.-Ing. (Ph.D Student) __________________________________________________ Institute of Orthopaedic Research and Biomechanics Director and Chair: Prof. Dr. Anita Ignatius Center of Musculoskeletal Research Ulm University Hospital Ulm Helmholtzstr. 14 89081 Ulm, Germany Phone: +49 731 500-55301 Fax: +49 731 500-55302 http://www.biomechanics.de ______________________________________________ R-help@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.
