Thank you once again Matt, I am sorry for sending just a portion of the log file. I thought that way it would be easier to look for the details. Won't happen again.
Jesús 2016-05-23 16:31 GMT-03:00 Matt Newville <newvi...@cars.uchicago.edu>: > Jesus, > > > On Mon, May 23, 2016 at 2:07 PM, Jesús Eduardo Vega Castillo < > jeve...@gmail.com> wrote: > >> Dear list, >> >> I made an EXAFS analysis in Artemis (in Demeter 0.9.22) using all the >> available variables. This is a fragment of the .log file I got: >> >> Independent points : 17.7666016 >> Number of variables : 17 >> Chi-square : 265.0947132 >> Reduced chi-square : 345.8050781 >> >> R-factor : 0.0026486 >> >> Number of data sets : 1 >> : k-range = 2.942 - 11.043 >> : dk = 1 >> : k-window = hanning >> : k-weight = 1,2,3 >> : R-range = 1.115 - 3.5 >> : dR = 0.0 >> : R-window = hanning >> : fitting space = r >> : background function = yes >> : phase correction = no >> : background removal = E0: 20002.215, Rbkg: 1.0, range: >> [2.25:17.4039986832903], clamps: 0/24, kw: 2 >> : epsilon_k by k-weight = 3.189e-004 >> : epsilon_r by k-weight = 2.339e-001 >> : R-factor by k-weight = 1 -> 0.00220, 2 -> 0.00224, 3 -> 0.00392 >> >> The problem is that when I use the Nyquist criterion >> >> Nind=2*deltak*deltar/pi + 1 >> >> for calculating the number of independent points the value I got is much >> lower and close to 13. >> >> I was not aware of this discrepancy and it caused a reviewer to think I >> made up the fit! >> >> > Sending the entire log file is always recommended. Otherwise, you are > selectively editing what you are telling us, and expecting us to guess what > you haven't told us. Sending the project file is often a good choice. > > Fortunately, you included an important clue. You have "background > function = yes", which means the fit will actually extend down to R=0, > using your Rmin as Rbkg in calculating how many variables are used for the > spline. With that included, the fit does contain approximately 18 > independent parameters, about 5 of which will be used for the background > subtraction. > > --Matt > > _______________________________________________ > Ifeffit mailing list > Ifeffit@millenia.cars.aps.anl.gov > http://millenia.cars.aps.anl.gov/mailman/listinfo/ifeffit > Unsubscribe: http://millenia.cars.aps.anl.gov/mailman/options/ifeffit > >
_______________________________________________ Ifeffit mailing list Ifeffit@millenia.cars.aps.anl.gov http://millenia.cars.aps.anl.gov/mailman/listinfo/ifeffit Unsubscribe: http://millenia.cars.aps.anl.gov/mailman/options/ifeffit