All Forums  Origin Forum  Origin Forum  Non-linear fit with low error in fitting paramete

Note: You must be registered in order to post a reply.
To register, click here. Registration is FREE!

Screensize: 640 x 480 800 x 600 1024 x 768 1280 x 1024 UserName: Password: Anti-Spam Code: Format Mode: Basic  Help  Prompt  Format: Font Andale Mono Arial Arial Black Book Antiqua Century Gothic Comic Sans MS Courier New Georgia Impact Lucida Console Script MT Bold Stencil Tahoma Times New Roman Trebuchet MS Verdana   Size 1 2 3 4 5 6   Color Black Red Yellow Pink Green Orange Purple Blue Beige Brown Teal Navy Maroon LimeGreen Message: * HTML is OFF * Forum Code is ON Smilies [quote][i]Originally posted by udhaya[/i] [br]I am trying to fit a dataset to an exponential decay function (nonlinear fit). As I start the fitting with the rough estimates of parameters, for the first few cycles of iteration I get a fitting curve which looks visually acceptable. The error values are low (< 5% of the three fitting parameters) and COD (R2) > 0.985. As soon as I increase the iterations by hitting "fit until converge", the resulting final parameters have error values > 100% of the fitting parameters with COD (R2) being > 0.99. I understand, the default criteria of fitting is to achieve COD(R2) as close to one as possible. Is there a way to achieve low error in fitting parameters at the cost of COD(R2)? It is possible to tell origin to iterate to maintain the error within a limit, while achieving the COD(R2) closest to unity! Will appreciate any help. Thanks [/quote]   Check here to include your profile signature. Check here to subscribe to this topic.