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Goodness of fit, Residual STD, chi square

  1. Mar 24, 2016 #1
    1. The problem statement, all variables and given/known data
    Hello,

    I am using CasaXPS to model synthetic peak models for X-ray photoelectron spectroscopy data. I am fitting.
    The software has a lot of manuals online but they do not explain how they yield a Residual Standard Deviation, after each fit iteration. Most software use Chi-square or Reduced-Chi-squares, which I do not really understand either, but they are more widely used.
    For example,
    upload_2016-3-25_3-18-40.png
    Whereas most softwares use Reduced Chi squares.
    Lastly,


    Name Block Id Data Set Position FWHM Area St Dev Area %At Conc % St.Dev. Goodness of Fit
    sp2 C1s 1-1 12 284.4560 1.1348 135.671 8.38179 54.79 286.976
    sp3 C1s 1-1 285.0000 1.2000 89.8416 8.55699 36.28 286.976
    sp2-Br C1s 1-1 285.6874 1.2000 14.7421 5.73433 5.95 286.976
    C=P C1s 1-1 284.4843 0.9000 7.37342 2.8681 2.98 286.976


    I get a report in which the "Goodness of Fit" equals 286.976, how do I transform this number into something statistically significant?
    The examples they use on the manuals also happen to have high numbers for "Goodness of Fit"
    Thanks a lot.
     

    Attached Files:

  2. jcsd
  3. Mar 26, 2016 #2

    mfb

    User Avatar
    2016 Award

    Staff: Mentor

    I think you'll have to check the manual how that property is defined.
     
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