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Hi Heiko,
with 'non extended chi^2 fit' I actually meant that I performed a 
minumum chi^2 fit with model that was built using a different syntax 
w.r.t. the one I have used until now...

If I have understood correctly, in RooFit when you specify the range for 
the numbers of events for all the PDF in your model, i.e.:

RooRealVar argusevent("","argus",10000,0,200000);   //Argus events
RooRealVar crisballevent("","crisball",10000,0,200000); //cb events
RooRealVar signalevent("","signal",10000,0,20000); //signal events

RooAbsPdf 
model("","model",RooArgList(argus,cristalball,signal),RooArgList(argusevent,crisball,signalevent));

the model is extended by default, while doing something like:

RooRealVar argusfrac("","argus",0.5,0,1);   //Argus fraction
RooRealVar signalfrac("","signal",0.5,0,1); //signal fraction

RooAbsPdf 
model("","model",RooArgList(argus,signal,cristalball),RooArgList(argusfrac,signalfrac));

the model is non-extended.

So this time I used the latter definition to build the model and then I 
performed the chi^2 fit.


	Antonio

Heiko Lacker ha scritto:
> Hi Antionio,
> 
> that looks now much better.
> 
> What is not cleat to me is your statement 
> that now it is 'non extended chi^2 fit'.
> 
> Could you please explain what you mean?
> 
> Cheers,
> Heiko
> 
> 
> On Wed, 3 May 2006, Antonio Petrella wrote:
> 
>> Hi Heiko,
>> I was just finishing the update of this section....
>>
>>
>>> I have just seen that there is something new.
>>>
>>> * You say that it is now a non-extended chi^2 fit.
>>>   Could you please give some technical details?
>>>   Also, it would be interesting to see the fitted 
>>>   parameters.
>>>
>> Now the table is complete!
>>
>>> * Should we compare these results with the ones
>>>   posted at April 12th?
>> No, those are wrong since there is no scaling with the errors.
>>
>>> * Could you please post on your webpage somewhere
>>>   the numbers of entries in the histo for
>>>   a) data
>>>   b) MC
>>>
>> Sure, I added these informations right below the title.
>> I write them also here:
>>
>> a) data = 437889
>> b) MC = 1561024
>>
>>> * It might be also helpful to provide the sum of the
>>>   fitted yields in order to see how it compares to the
>>>   number of entries in the histo.
>>>
>> Ok, I will add this now.
>>
>> Bye,
>>     Antonio
>>
>>> Cheers,
>>> Heiko