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https://issues.apache.org/jira/browse/LUCENE-8197?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16401403#comment-16401403
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Robert Muir commented on LUCENE-8197:
-------------------------------------

and just to be clear, i dont want to hide the formula. user should be in 
control of parameters weight/scaling factor so the formula is transparent. but 
they can always add a boost so can the default weight be something uber-simple? 
As far as scaling factor, well you already have a simple default for the 
two-parameter case, but for the 1-parameter case is there anything we can do 
that is simple? its a log either way, so we are a far cry from the previous 
crazy stuff with lucene's sqrt() :) 

just brainstorming to make it really easy to get the query integrated into 
various query parsers and stuff, but still be clear to people who really give a 
crap.

> Make top-k queries fast when static scoring signals are incorporated into the 
> score
> -----------------------------------------------------------------------------------
>
>                 Key: LUCENE-8197
>                 URL: https://issues.apache.org/jira/browse/LUCENE-8197
>             Project: Lucene - Core
>          Issue Type: Improvement
>            Reporter: Adrien Grand
>            Priority: Minor
>             Fix For: master (8.0)
>
>         Attachments: LUCENE-8197.patch, LUCENE-8197.patch, LUCENE-8197.patch
>
>
> Block-max WAND (LUCENE-8135) and some earlier issues made Lucene faster at 
> computing the top-k matches of boolean queries.
> It is quite frequent that users want to improve ranking and end up scoring 
> with a formula that could look like {{bm25_score + w * log(alpha + 
> pagerank)}} (w and alpha being constants, and pagerank being a per-document 
> field value). You could do this with doc values and {{FunctionScoreQuery}} 
> but unfortunately this will remove the ability to optimize top-k queries 
> since the scoring formula becomes opaque to Lucene.
> I'd like to add a new field that allows to store such scoring signals as term 
> frequencies, and new queries that could produce {{log(alpha + pagerank)}} as 
> a score. Then implementing the above formula can be done by boosting this 
> query with a boost equal to {{w}} and adding this boosted query as a SHOULD 
> clause of a {{BooleanQuery}}. This would give Lucene the ability to compute 
> top-k hits faster, especially but not only if the index is sorted by 
> decreasing pagerank.



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