Hi Shelly, Right now, minimize() doesn't report an r-factor, (does the doc say somewhere that an R-factor is reported?). minimize() does generate and report values for chi-square and reduced chi-square. chi-square = sum-of-squares < residual / uncertainty > where 'residual' is the array to minimize and 'uncertainty' is an array of uncertainties, one value for each point in the residual. If no uncertainty is given, the uncertainties are set to 1. reduced chi-square is simply reduced chi-square = chi-square / (npts(residual) - n_variables) minimize() is flexible enough that you could include the uncertainties in the definition of the function to minimize. It's also flexible enough to let you cheat, and scale chi-square anyway you want, for good or bad.... The reported uncertainties in the parameters follows the 'normal' rule of increasing chi-square by reduced-chi-square. An R-factor might be useful, I suppose .... --Matt On Tue, 28 Jan 2003, Kelly, Shelly D. wrote:
Hi,
I would like to use the minimize function to fit a line to some data points. I could not find documentation on the r-square factor that is referred to as the confidence level for the fit.
Thanks Shelly
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