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From ragi <raghuveer.kanche...@gmail.com>
Subject Re: Is negative boost possible?
Date Sun, 11 Oct 2009 04:07:19 GMT

If you dont want to do a pure negative query and just want boost a few
documents down based on a matching criteria try to use linear function (one
of the functions available in boost function) with a negative m (slope).
We could solve our problem this way.


We wanted to do negatively boost some documents based on certain keywords
while 

Marc Sturlese wrote:
> 
> 
> :>the only way to "negative boost" is to "positively boost" the inverse...
> :>
> :>	(*:* -field1:value_to_penalize)^10
> 
> This will do the job aswell as bq supports pure negative queries (at least
> in trunk):
> bq=-field1:value_to_penalize^10
> 
> http://wiki.apache.org/solr/SolrRelevancyFAQ#head-76e53db8c5fd31133dc3566318d1aad2bb23e07e
> 
> 
> hossman wrote:
>> 
>> 
>> : Use decimal figure less than 1, e.g. 0.5, to express less importance.
>> 
>> but that's stil la positive boost ... it still increases the scores of 
>> documents that match.
>> 
>> the only way to "negative boost" is to "positively boost" the inverse...
>> 
>> 	(*:* -field1:value_to_penalize)^10
>> 
>> : > I am looking for a way to assign negative boost to a term in Solr
>> query.
>> : > Our use scenario is that we want to boost matching documents that are
>> : > updated recently and penalize those that have not been updated for a
>> long
>> : > time.  There are other terms in the query that would affect the
>> scores as
>> : > well.  For example we construct a query similar to this:
>> : > 
>> : > *:* field1:value1^2  field2:value2^2 lastUpdateTime:[NOW/DAY-90DAYS
>> TO *]^5
>> : > lastUpdateTime:[* TO NOW/DAY-365DAYS]^-3
>> : > 
>> : > I notice it's not possible to simply use a negative boosting factor
>> in the
>> : > query.  Is there any way to achieve such result?
>> : > 
>> : > Regards,
>> : > Shi Quan He
>> : > 
>> : >   
>> 
>> 
>> 
>> -Hoss
>> 
>> 
>> 
> 
> 

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