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<font size="+1">Matt,<br>
Good explanation! The point of getting people together to agree
on our next steps is to get things clarified in just this way, so
that our end state can be seen to be appropriate. We are in fact
behind at this point, so some catch-up is needed. I'm happy this
this discussion has moved into cyberspace for this kind of broader
discussion (including Curtis' comments on simulation).<br>
Chip<br>
<br>
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<div class="moz-cite-prefix">On 7/31/14 12:17 PM, Matthew Shepherd
wrote:<br>
</div>
<blockquote
cite="mid:19A5813A-2255-4C36-94C1-C4174C3C1749@indiana.edu"
type="cite">
<pre wrap="">Chip,
Making n-tuples available is a natural instinct, but
I don't think it will be practically useful.
To make a reanalysis useful you
not only need the four vectors, but also code to simulate
the detector and explore the acceptance of the new cuts.
Then you may need other data to understand the
systematic uncertainties in the cuts. Is is hard to
imagine someone doing a robust re-analysis without
complete access to the GlueX data set and software.
(Here I define "robust" as "capable of publishing
in a peer reviewed journal.") This is just my opinion --
I think we'll spend a lot of time doing this and people
may download and play with the data, but it will
just be playing. I don't think useful cross-checks
or additional publishable results can be obtained from
an ntuple alone.
Most key GlueX results won't be 1D histograms but
results of amplitude analyses. Each such analysis
will contain a lot of data -- likely thousands of fit
parameters, many of which will have non-trivial correlations.
These results are useful and able to be reanalyzed
as they will represent "pure quantities" (with
detector effects removed and systematic errors
quantified).
We should focus on a standard way to make the results
of GlueX amplitude analysis available to the
community with all the proper correlation matrices
etc. so that it can be reanalyzed. This is an
absolute necessity in the context of doing
combined fits from multiple experiments that people
talk about as a long term goal.
Matt</pre>
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