FAQ
i see, your idea would definitely simplify some things.

What about the index size difference between this approach and using
separate index? Would this separate field increase index size?

I guess my line of thinking is if you have 10 docs with robert, with
separate index you just have robert, and its deletion neighborhood one time.
with this approach you have the same thing, but at least you must have
document numbers and the other inverted index stuff with each neighborhood
term. would this be a significant change to size and/or performance? and
since the documents have multiple terms there is additional positional
information for slop factor for each neighborhood term...

i think its worth investigating, maybe performance would actually be better,
just curious. i think i boxed myself in to auxiliary index because of some
other irrelevant thigns i am doing.
On Tue, Jan 6, 2009 at 4:42 PM, robert engels wrote:

I don't think that is the case. You will have single deletion neighborhood.
The number of unique terms in the field is going to be the union of the
deletion dictionaries of each source term.
For example, given the following documents A which have field 'X' with
value best, and document B with value jest (and k == 1).

A will generate est bst, bet, bes, B will generate est, jest, jst, jes

so field FieldXFuzzy contains (est:AB,bst:A,bet:A,bes:A,jest:B,jst:B,jes)

I don't think the storage requirement is any greater doing it this way.

3.2.1 Indexing
For all words in a dictionary, and a given number of edit operations k,
FastSS
generates all variant spellings recursively and save them as tuples of type

v′ ∈ Ud (v, k) → (v, x) where v is a dictionary word and x a list of
deletion
positions.

Theorem 5. Index uses O(nmk+1) space, as it stores al l the variants for n

dictionary words of length m with k mismatches.

3.2.2 Retrieval
For a query p and edit distance k, first generate the neighborhood Ud (p,
k).
Then compare the words in the neighborhood with the index, and find
matching candidates. Compare deletion positions for each candidate with
the deletion positions in U(p, k), using Theorem 4.

--
Robert Muir
rcmuir@gmail.com

Related Discussions

 view thread | post posts ‹ prev | 9 of 18 | next ›
Discussion Overview
 group dev categories lucene posted Jan 6, '09 at 6:03p active Feb 19, '10 at 9:28p posts 18 users 3 website lucene.apache.org

3 users in discussion

Content

People

Support

Translate

site design / logo © 2021 Grokbase