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Topic: Chi -squared Fitting problem
Replies: 5   Last Post: Feb 25, 2005 7:42 AM

 Messages: [ Previous | Next ]
 sean Posts: 6 Registered: 12/13/04
Re: Chi -squared Fitting problem
Posted: Feb 24, 2005 9:50 AM

Your logic in this argument does not make sense to me. For
instance I believe that you do agree that s is calculated
only by performing the chi squared fitting in maple or manually.
Ie in this formula
I(t) = Imax * ( fR((t-tmax)/w) + b
all the variables are known from the template and tables and
z is supplied as the redshift value for each SN. So s is
the unknown that is calculated by the chi fitting. In other
words you cant find out s until you have done the chi
squared fit.
Yet you contradict yourself and say that you dont have to do the
fit to find out what s is when z is either .49 or 0.
Dont you see how that does not make sense?
For instance here I will set you a test.
You claim that you can calculate s just by looking at the formula
. So I will set you a test to derive s for a SN where z=0.49
I know what s is because I have taken it from another paper where
someone else has already calculated it so I can check if your

Now according to your logic the formula `tells` you
what s will be. So please what does the formula tell you
what s is for that SN where z=0.49?
And then, what is s where z=0 for that SN?
Do you still `hear` the formula telling you the answer
or will you now admit that you have to do the chi
squared fit to derive s where z=.49 and z=0
And if you admit that you have to do the fit then that
you can `hear `the answer because the formula is `telling`

Date Subject Author
2/22/05 sean
2/22/05 Joseph Fagan
2/22/05 Bjoern Feuerbacher
2/22/05 Bjoern Feuerbacher
2/24/05 sean
2/25/05 Bjoern Feuerbacher