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https://issues.apache.org/jira/browse/LUCENE-3726?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13195932#comment-13195932
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Christian Moen commented on LUCENE-3726:
----------------------------------------

I've improved the heuristic and submitted a patch to LUCENE-3730, which covers 
the issue.

We can now deal with cases such as コニカミノルタホールディングス and many others just fine.  
The former becomes コニカ  ミノルタ  ホールディングス as we'd like.

I think we should apply LUCENE-3730 before changing any defaults -- and also 
independently of changing any defaults.  I think we should also make sure that 
the default we use for Lucene is consistent with the Solr's default in 
{{schema.xml}} for {{text_ja}}.

I'll do additional tests on a Japanese corpus and provide feedback, and we can 
use this as a basis for how to follow up.  Hopefully, we'll have sufficient and 
good data to conclude on this.

                
> Default KuromojiAnalyzer to use search mode
> -------------------------------------------
>
>                 Key: LUCENE-3726
>                 URL: https://issues.apache.org/jira/browse/LUCENE-3726
>             Project: Lucene - Java
>          Issue Type: Improvement
>    Affects Versions: 3.6, 4.0
>            Reporter: Robert Muir
>
> Kuromoji supports an option to segment text in a way more suitable for search,
> by preventing long compound nouns as indexing terms.
> In general 'how you segment' can be important depending on the application 
> (see http://nlp.stanford.edu/pubs/acl-wmt08-cws.pdf for some studies on this 
> in chinese)
> The current algorithm punishes the cost based on some parameters 
> (SEARCH_MODE_PENALTY, SEARCH_MODE_LENGTH, etc)
> for long runs of kanji.
> Some questions (these can be separate future issues if any useful ideas come 
> out):
> * should these parameters continue to be static-final, or configurable?
> * should POS also play a role in the algorithm (can/should we refine exactly 
> what we decompound)?
> * is the Tokenizer the best place to do this, or should we do it in a 
> tokenfilter? or both?
>   with a tokenfilter, one idea would be to also preserve the original 
> indexing term, overlapping it: e.g. ABCD -> AB, CD, ABCD(posInc=0)
>   from my understanding this tends to help with noun compounds in other 
> languages, because IDF of the original term boosts 'exact' compound matches.
>   but does a tokenfilter provide the segmenter enough 'context' to do this 
> properly?
> Either way, I think as a start we should turn on what we have by default: its 
> likely a very easy win.

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