rity</code> is an extension of 
 <a href="http://lucene.apache.org/core/5_1_0/core/org/apache/lucene/search/similarities/DefaultSimilarity.html?is-external=true" title="class or interface in org.apache.lucene.search.similarities"><code>DefaultSimilarity</code></a> that provides additional tuning options for 
 specifying the "sweetspot" of optimal <code>tf</code> and 
 <code>lengthNorm</code> values in the source data.
 </p>
 <p>
 In addition to the <code>discountOverlaps</code> init param supported by 
 <a 