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Re: Calculate R-squared value from gnuplot 'fit' output?

From	ab <ab.3942@googlemail.com>
Newsgroups	comp.graphics.apps.gnuplot
Subject	Re: Calculate R-squared value from gnuplot 'fit' output?
Date	2012-01-02 00:37 -0800
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>
> Why does that take 3 iterations? That is just a linear LS problem?
> Linear LS regression has an analytical solution, i.e. with normal
> equations.
> Solution should be either intelligent starting values or one iteration
> from

Hi,

You can force the fit  to converge in one iteration by using
FIT_START_LAMBDA=1.e-15
FIT_MAXITER=1
This is only suited for a linear model.

A better way is the stats command in gnuplot 4.5.
The correlation coefficient  r is calculated directly.

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Calculate R-squared value from gnuplot 'fit' output? Mike <mesimms@gmail.com> - 2011-12-28 12:14 -0800
  Re: Calculate R-squared value from gnuplot 'fit' output? Hans-Bernhard Bröker <HBBroeker@t-online.de> - 2011-12-28 22:11 +0100
  Re: Calculate R-squared value from gnuplot 'fit' output? wolfgang <cmat.wolfgang@gmail.com> - 2011-12-29 00:17 -0800
    Re: Calculate R-squared value from gnuplot 'fit' output? Hans-Bernhard Bröker <HBBroeker@t-online.de> - 2011-12-29 12:39 +0100
    Re: Calculate R-squared value from gnuplot 'fit' output? ab <ab.3942@googlemail.com> - 2012-01-02 00:37 -0800

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