Can some one explain (or quote a reference) to compare the scoring mechanism used by SOLR and LUCENE in simpler words. Is there any difference in them;
I am not that good at solr/lucene but my finding showed as if they are different.
P.S: i just tries a simple query like "+Contents:risk" and didn't use any filter other stuff.
Lucene uses concepts from the Vector space model to compute the score of documents. In summary, queries and documents can be seen as vectors. To compute the score of a document for a particular query, Lucene calculates how near each document's vector are from the query's vector. The more a document is near the query in VSM, the higher the score. You can have more details by looking at Lucene's Similarity class and Lucene's Scoring document.
The actual formula can be found in the Similarity javadocs.
Here's a summary of the parameters involved and a brief description of what they mean.
Solr uses Lucene under the hood, and by default Solr uses the default Lucene similarity algorithm.
