TOP and SCORE

[Arnold Rots]

What I proposed from the start was that SCORE would be input as well
as output parameter - and that's the way we have implemented it.
SCORE can have two values on input: "ALL" (default) and "TOP".
What I was suggesting does not require normalization, since 
SCORE=5 would be short for SCORE="TOP 5".

And my objection remains.  There is no other case where the name of
the parameter is different in input and output - and SCORE and TOP
refer to the same parameter.

  - Arnold

Doug Tody wrote:
> Hi Arnold -
> 
> I am not sure where you got this from: the mention of "score" in connection
> with SIA referred to this as a service capability not as a parameter
> (along with logical names, compression, etc.).  The query parameter
> proposed in both cases is TOP.  TOP=N returns the top scoring N records.
> To have a query parameter SCORE could also be useful but this would only
> work if the score were normalized in some fashion.  In all the discussions
> we have had of the SCORE heuristic the consensus has always been that
> we don't want to try to normalize the score, mainly because the scoring
> heuristic used is not defined except in general terms (intentionally, to
> allow smart heuristics to be developed), and would vary from one service
> implementation to the next, making it difficult to compare score values.
> 
>  	- Doug
> 
> 
> 
> On Tue, 26 Jul 2005, Arnold Rots wrote:
> 
> > Doug,
> >
> > I noticed in your presentation at the NVO team meeting that there are
> > two query parameters that overlap between SIAP and SSAP: SCORE and TOP.
> > They represent the same concept; to amke it worse, "TOP" is an allowed
> > value of SCORE.  I think that is confusing and undesirable.
> >
> > I would suggest that TOP be dropped and SCORE be used in both cases.
> > If it is considered important to allow a service to return a number of
> > records other than 1 or ALL, one might consider allowing an integer
> > value for SCORE (as for TOP), in addition to "ALL" and "TOP".
> >
> > Cheers,
> >
> >   - Arnold
> >
> > --------------------------------------------------------------------------
> > Arnold H. Rots                                Chandra X-ray Science Center
> > Smithsonian Astrophysical Observatory                tel:  +1 617 496 7701
> > 60 Garden Street, MS 67                              fax:  +1 617 495 7356
> > Cambridge, MA 02138                             arots at head.cfa.harvard.edu
> > USA                                     http://hea-www.harvard.edu/~arots/
> > --------------------------------------------------------------------------
> >
> >
> 
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Arnold H. Rots                                Chandra X-ray Science Center
Smithsonian Astrophysical Observatory                tel:  +1 617 496 7701
60 Garden Street, MS 67                              fax:  +1 617 495 7356
Cambridge, MA 02138                             arots at head.cfa.harvard.edu
USA                                     http://hea-www.harvard.edu/~arots/
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