TOP and SCORE

[Marco C. Leoni]

I think it would be nice to have both parameters.

TOP should be used to indicate how many records to send back, maybe with 
a default value, e.g. all the records if is null or not present.

On the other hand, SCORE should express the ranking according to the 
algorithm used - if any.


Cheers,
    Marco

On 26/07/2005 21:38, Arnold Rots wrote:

>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/
>>>--------------------------------------------------------------------------
>>>
>>>
>>>      
>>>
>--------------------------------------------------------------------------
>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/
>--------------------------------------------------------------------------
>