How do I sort search results by relevance?

Question

I'm working on a project which searches through a database, then sorts the search results by relevance, according to a string the user inputs. I think my current search is fairly decent, but the comparator I wrote to sort the results by relevance is giving me funny results. I don’t know what to consider relevant. I know this is a big branch of information retrieval, but I have no idea where to start finding examples of searches which sort objects by relevance and would appreciate any feedback.

To give a little more background about my specific issue, the user will input a string in a website database, which stores objects (items in the store) with various fields, such as a minor and major classification (for example, an XBox 360 game might be stored with major=video_games and minor=xbox360 fields along with its specific name). The four main fields that I think should be considered in the search are the specific name, major, minor, and genre of the type of object, if that helps.

Lucene does that. If you don't want to use it, you could look at their code for ideas. — BillRobertson42, Dec 27 '11 at 03:35
Thanks Oli! I've looked into Lucene; I thought it may have been a bit heavy for my purposes, but I'll look into it further. — Salmontres, Dec 27 '11 at 05:04

score 1 · Answer 1 · answered Jan 20 '12 at 22:58

In case you don't wanna use lucene/Solr, you can always use distance metrics to find the similarity between query and the rows retrieved from database. Once you get the score you can sort them and they will be considered as sorted by relevance.

This is what exactly happens behind the scene of lucene. You can use simple similarity metrics like manhattan distance, distance of points in n-dimensional space etc. Look for lucene scoring formula for more insight.

How do I sort search results by relevance?

1 Answers1