Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

A Trying several fits with only 2 functions?

  1. Jun 2, 2016 #1

    ChrisVer

    User Avatar
    Gold Member

    Well I was reading this paper http://inspirehep.net/record/1409825
    and came across this comment:
    My question is basically a statistical one.... how can you make several fits using only 2 fitting functions?
    Or do they mean something like fitting with func1 in some ranges [a,b] with a,b varying?
    Also I do not understand well the uncertainty evaluation using the RMS of all attempted fits [how it works statistically].
     
  2. jcsd
  3. Jun 2, 2016 #2

    mfb

    User Avatar
    2016 Award

    Staff: Mentor

    That's how I would interpret the different fit ranges they tested.
    For a given m_T, you look at the average and RMS of all the values the different fits have at that point.
     
  4. Jun 2, 2016 #3

    ChrisVer

    User Avatar
    Gold Member

    hmm... even if those fits were made over a partially common range? eg [200,300] and [250,400] ?
     
  5. Jun 2, 2016 #4

    mfb

    User Avatar
    2016 Award

    Staff: Mentor

    The fits are correlated, sure, but you are not studying the sensitivity to the data fluctuations here, only the sensitivity to the fit method.
     
  6. Jun 2, 2016 #5

    ChrisVer

    User Avatar
    Gold Member

    well my problem mainly comes from such a sketch I did on the scratch (so sorry for the wriggles and so on)...
    maxresdefault.jpg
    Obviously trying to determine an error based on what values the f1 and f2 have in some ranges (at eg the blue's peak) can be problematic...especially if your best fit happens to be that of f1.
     
    Last edited: Jun 2, 2016
  7. Jun 2, 2016 #6

    mfb

    User Avatar
    2016 Award

    Staff: Mentor

    Well, if the fits look like that, you are doing something wrong.
     
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Have something to add?
Draft saved Draft deleted



Similar Discussions: Trying several fits with only 2 functions?
Loading...