You learned the gosh-darndest things:
http://localhost:8983/solr/browse?q=ipod&boost=product(price,-2)&debugQuery=on
…nets:
-0.3797992 = (MATCH) sum of:
0.13510442 = (MATCH) max of:
0.045963455 = (MATCH) weight(text:ipod^0.5 in 4) [DefaultSimilarity],
result of:
0.045963455 = score(doc=4,freq=3.0 = termFreq=3.0
), product of:
…blah blah blah…
-0.5149036 = (MATCH) FunctionQuery(product(float(price),const(-2))), product
of:
-23.0 = product(float(price)=11.5,const(-2))
1.0 = boost
0.022387113 = queryNorm
it works Similarly with boost=
-3.1081805 = (MATCH) boost((id:ipod^10.0 | author:ipod^2.0 | title:ipod^10.0 |
text:ipod^0.5 | cat:ipod^1.4 | keywords:ipod^5.0 | manu:ipod^1.1 |
description:ipod^5.0 | resourcename:ipod | name:ipod^1.2 | features:ipod |
sku:ipod^1.5),product(float(price),const(-2))), product of:
0.13513829 = (MATCH) max of:
0.045974977 = (MATCH) weight(text:ipod^0.5 in 4) [DefaultSimilarity],
result of:
0.045974977 = score(doc=4,freq=3.0 = termFreq=3.0
), product of:
…more blah…
-23.0 = product(float(price)=11.5,const(-2))
I wonder how fantastically this can be abused now?
On May 10, 2013, at 7:22 AM, "Dyer, James" <james.d...@ingramcontent.com> wrote:
> Despite the discussion in SOLR-3823/SOLR-3278, my experience with Solr 4.2 is
> that it does indeed allow negative boosts on both "bf" and "qf". I think the
> functionality was added under the radar possibly with SOLR-4093, not sure
> though. In disbelief, I did some testing and it seems to really work.
>
> James Dyer
> Ingram Content Group
> (615) 213-4311
>
>
> -----Original Message-----
> From: Jack Krupansky [mailto:j...@basetechnology.com]
> Sent: Thursday, May 09, 2013 5:41 PM
> To: solr-user@lucene.apache.org
> Subject: Re: Negative Boosting at Recent Versions of Solr?
>
> Solr does support both additive and multiplicative boosts. Although Solr
> doesn't support negative multiplicative boosts on query terms, it does
> support fractional multiplicative boosts (0.25) which do allow you to
> de-boost a term.
>
> The boosts for individual query terms and for the edismax "qf" parameter
> cannot be negative, but can be fractional.
>
> The edismax "bf" parameter give a function query that provides an additive
> boost, which could be negative.
>
> The edismax "boost" parameter gives a function query that provides a
> multiplicative boost - which could be negative, so it’s not absolutely true
> that doesn't support negative boosts.
>
> -- Jack Krupansky
>
> -----Original Message-----
> From: Furkan KAMACI
> Sent: Thursday, May 09, 2013 6:08 PM
> To: solr-user@lucene.apache.org
> Subject: Negative Boosting at Recent Versions of Solr?
>
> I know that whilst Lucene allows negative boosts, Solr does not. However
> did it change with newer versions of Solr (I use Solr 4.2.1) or still same?
>
>
