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Logistics Rgression in Statistics 2 - chris.bragg - 11-13-2016 10:00 PM
The manual indicates that if you store a value in the real variable "L" (other than ZERO) then it will be taken as the "saturation" value in determining the best fit parameters for a logistic function (regression model). This does not seem to work. The system provides its own estimate for "L".
Has anyone a solution or is this a bug.
RE: Logistics Rgression in Statistics 2 - mark4flies - 11-14-2016 12:51 PM
I just confirmed that the procedure will fit the model parameter L. It is not the global variable L, as far as I can tell. I set to a value and refit the data, with the same result as the first time. (Confirming your claim.) How did you try to fix this parameter to a particular value?
I wonder if it checks for L undefined (L=0) only once or every time? L was undefined the first time I fit data.
RE: Logistics Rgression in Statistics 2 - Tim Wessman - 11-14-2016 03:55 PM
Well, this is the first time I'm hearing about this "feature" and I wrote the logistic regression code so...
Seems like a case of the person writing the documentation including a feature that wasn't included in a note to the developers.
I'll put it on the list and see what can be done.
RE: Logistics Rgression in Statistics 2 - chris.bragg - 11-14-2016 11:26 PM
Tim,
Thanks. It would make the function more useful from a teaching perspective - biology projects.
Regards
Chris Bragg