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https://issues.apache.org/jira/browse/JENA-242?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13267710#comment-13267710
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Stephen Allen commented on JENA-242:
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I haven't really had a chance to use LARQ much, but I'm not sure that
normalizing the scores is necessarily the best thing to do. It makes a bunch
of assumptions (underlying data isn't changing, that there is a linear
relationship between scores, that scores mean something across queries, etc).
Importantly, as the scores between different queries are not related to each
other, an arbitrary value for the FILTER clause doesn't make sense. If the
result of your query was a bunch of really bad matches, but they all had the
same score, then they'd show up as 100% relevance, and then pass your filter
(see [1]).
Instead, I think you should use ORDER BY on the score, and then maybe LIMIT the
results to a subset. Or if you really must have a normalized result, then
retrieve all the results and calculate the normalized score in your application
(although I encourage you not to). More info about scoring at [2].
[1] http://wiki.apache.org/lucene-java/ScoresAsPercentages
[2] http://lucene.apache.org/core/3_6_0/scoring.html
> LARQ scores not normalized
> --------------------------
>
> Key: JENA-242
> URL: https://issues.apache.org/jira/browse/JENA-242
> Project: Apache Jena
> Issue Type: Bug
> Components: LARQ
> Affects Versions: LARQ 1.0.0
> Environment: Fuseki
> Reporter: laotao
>
> In previous versions the LARQ score seemed to be normalized to range [0, 1].
> In LARQ 1.0.0 some scores can be higher than 1.
> Normalized scores are needed to filter sparql results (so that only items
> above certain quality is shown).
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