FuzzyQuery - fuzzy terms and misspellings are ranked higher than exact matches [LUCENE-2557]

The FuzzyQuery often causes misspellings to be ranked higher than the exact match, which seems to be an undesirable property generally.

For example, in an index of surnames, if I search using a FuzzyQuery for "smith", the misspellings such as "smiith", or "smiht" would appear near the top of the search results ahead of documents that match "smith".

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Migrated from [LUCENE-2557](https://issues.apache.org/jira/browse/LUCENE-2557) by Jingkei Ly, 1 vote, updated Mar 09 2012
Attachments: [idf-scoring-test-case.patch](https://apache.github.io/lucene-jira-archive/attachments/LUCENE-2557/idf-scoring-test-case.patch), [LUCENE-2557.patch](https://apache.github.io/lucene-jira-archive/attachments/LUCENE-2557/LUCENE-2557.patch)

Start at the FuzzyQuery entry point and review the attached idf-scoring-test-case.patch and LUCENE-2557.patch to understand the reported ranking behavior. Confirm the result with the surname example described in the issue; done means exact matches rank above fuzzy misspellings without breaking fuzzy matching.

Written by the indexing model from the issue text.