Is it possible to affect a Lucene rank based on a numeric value?

Question

I have content with various numeric values, and a higher value indicates (theoretically) more valuable content, which I want to rank higher.

For instance:

• Average rating (0 - 5)
• Number of comments (0 - whatever)
• Number of inbound link references from other pages (0 - whatever)
• Some arbitrary number I apply to indicate how important I feel the content is (1 - whatever)

These can be indexed by Lucene as a numeric value, but how can I tell Lucene to use this value in its ranking algorithm?

Answer 1

Depending how exactly you want to proceed, you can set boost while indexing as suggested by @L.B, or if you want to make it dynamic, i.e. at search time rather than indexing time, you can use ValueSourceQuery and CustomScoreQuery.

You can see example in the question I asked some time ago: Lucene custom scoring for numeric fields (the example was tested with Lucene 3.0).

Answer 2

you can set this value using "Field.SetBoost" while indexing.