• Measuring Search Relevance using NDCG

    By: Vijay Mhaskar | June 28, 2015

    Normalized Discounted Cumulative Gain (NDCG) is popular method for measuring the quality of a set of search results. It asserts the following: Very relevant results are more useful than somewhat relevant results which are more

  • Query Rescoring in Solr

    By: Vijay Mhaskar | June 19, 2015

    Introduction Sometimes relevance requirements are very complex and creates performance issues during execution. There is a very nice feature Introduced in Solr 4.9¬†called “Query Reranking/Rescoring”¬†(SOLR-6088) which allows us to run our query with a less

  • Exactish phrase matching in Solr

    By: Vijay Mhaskar | May 28, 2015

    Phrase match Simple way by which we an achieve exact matching in Solr is by using the default string type. It is exact phrase matching. string is a useful type for facet where we search