Tobias Henkel
Germany
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Posted - 06/16/2007 : 06:24:17 AM
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Origin Student Version 7.5 Windows XP
I have a problem with the advanced fitting tool. I would like to fit a function of three variables (x1,x2,x3) to the form:
y= (b0 + b1*x1 + b2*x1^2 + b3*x1^3 + b4*x2 + b5*x2^2 + b5*x2^3) * x3
I'm able to compile this function and run the fitting procedure. As results I recieve the parameter values with reasonable error margins (report log) and the fitted functions depicts my measured values quite well as indicated by the plotted red graph and a modell description level (R^2) of about 0.97. If I use these determined parameters, however, to recalculate my data with the function stated above than this fails.
Has anybody got an idea what's going wrong?
Kind regards Tobias H.
Edited by - Tobias Henkel on 06/16/2007 07:51:45 AM |
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