lucene-solr-user mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From "Yonik Seeley" <yo...@apache.org>
Subject Re: relevance ranking and scoring
Date Wed, 24 Jan 2007 16:23:56 GMT
On 1/24/07, Andrew Nagy <andrew.nagy@villanova.edu> wrote:
> > Let's start with the first... add a debugQuery=on
> > parameter to your request and post the full result here.
> > You can get the same effect through the
> > query form on the solr admin pages by checking the "Debug: explain"
> > checkbox.
> I attached the results to my last email, are you not able to see them?

Ahh, I missed it.

Ok, here is your query:
 <str name="rawquerystring">title:(gone with the wind) OR title2:(gone
with the wind)</str>
And here it is parsed:
 <str name="parsedquery">(title:gone title:wind) (title2:gone title2:wind)</str>

First, notice how stopwords were removed, so "with" and "the" will not
count in the results.

You are querying across two different fields.
Notice how the first two documents both have "wind" in both title and title2,
while the third document "gone with the wind" has no title2 field (and
hence can't match on it).

In the first documents, the scores for the matches on title and title2
both contribute to the score.  For the third document, it's penalized
by not matching in both the title and title2 field.

You could look at the dismax handler... it helps constructs queries, a
component of which are DisjunctionMaxQueries (they don't add together
scores from different fields, but just take the highest score from any
matching field for a term).

You could also see how changing or removing the stopword list affects relevance.

-Yonik

Mime
View raw message