[Halld-tracking-hw] Pull Distributions

[Curtis A. Meyer]

Hi Everyone -

   attached is a pdf file that is the chapter of a Ph.D. thesis that 
talks about
kinematic fitting. Section 6.1.2 talks about the pull distributions and 
formula
6.6 is as I remember it with the denominator having a difference inside the
square root.

    I also recall many years ago looking into what happens when the 
error matricies
are not diagonal. The denominator is defined only using the diagonal 
elements
of the covariance matrix, both for starting values and the fit values.

    With regard for Simon's work, where he is looking at individual 
tracks, I am
not 100% sure how to apply this though. The error matrix is the result 
of the fit.
In Jake's work, it is clearer a we have the pull's from the tracking, 
and then the
improved pulls after the kinematic fit.

    curtis

-- 
Prof. Curtis A. Meyer		Department of Physics
Phone:	(412) 268-2745		Carnegie Mellon University
Fax:	(412) 681-0648		Pittsburgh PA 15213-3890
cmeyer at ernest.phys.cmu.edu	http://www.curtismeyer.com/


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