You are viewing a plain text version of this content. The canonical link for it is here.
Posted to dev@lucene.apache.org by "Robert Muir (JIRA)" <ji...@apache.org> on 2011/06/20 13:45:47 UTC
[jira] [Resolved] (LUCENE-3174) Similarity.Stats class for term &
collection statistics
[ https://issues.apache.org/jira/browse/LUCENE-3174?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]
Robert Muir resolved LUCENE-3174.
---------------------------------
Resolution: Fixed
thanks David!
> Similarity.Stats class for term & collection statistics
> -------------------------------------------------------
>
> Key: LUCENE-3174
> URL: https://issues.apache.org/jira/browse/LUCENE-3174
> Project: Lucene - Java
> Issue Type: Sub-task
> Components: core/search
> Affects Versions: flexscoring branch
> Reporter: David Mark Nemeskey
> Assignee: David Mark Nemeskey
> Priority: Minor
> Fix For: flexscoring branch
>
> Attachments: LUCENE-3174.patch, LUCENE-3174.patch, LUCENE-3174.patch, LUCENE-3174.patch, LUCENE-3174.patch, LUCENE-3174.patch, LUCENE-3174_normalize_boost.patch
>
>
> In order to support ranking methods besides TF-IDF, we need to make the statistics they need available. These statistics could be computed in computeWeight (soon to become computeStats) and stored in a separate object for easy access. Since this object will be used solely by subclasses of Similarity, it should be implented as a static inner class, i.e. Similarity.Stats.
> There are two ways this could be implemented:
> - as a single Similarity.Stats class, reused by all ranking algorithms. In this case, this class would have a member field for all statistics;
> - as a hierarchy of Stats classes, one for each ranking algorithm. Each subclass would define only the statistics needed for the ranking algorithm.
> In the second case, the Stats class in DefaultSimilarity would have a single field, idf, while the one in e.g. BM25Similarity would have idf and average field/document length.
--
This message is automatically generated by JIRA.
For more information on JIRA, see: http://www.atlassian.com/software/jira
---------------------------------------------------------------------
To unsubscribe, e-mail: dev-unsubscribe@lucene.apache.org
For additional commands, e-mail: dev-help@lucene.apache.org