Menu
Home
People
Places
Arts
History
Plants & Animals
Science
Life & Culture
Technology
Reference.org
Jaccard index
open-in-new
<p>The Jaccard index is a <a href="/facts/Statistic/av21WaMK">statistic</a> used for gauging the <a href="/facts/Similarity_measure/FmmFco8c">similarity</a> and <a href="/facts/Diversity_index/E6NWQEry">diversity</a> of <a href="/facts/Sample_(statistics)/URCwKNge">sample</a> sets. It is defined in general taking the ratio of two sizes (areas or volumes), the intersection size divided by the union size, also called intersection over union (IoU). </p><p>It was developed by <a href="/facts/Grove_Karl_Gilbert/0GxCdM0n">Grove Karl Gilbert</a> in 1884 as his ratio of verification (v) and now is often called the critical success index in meteorology. It was later developed independently by <a href="/facts/Paul_Jaccard/7FWJf4U0">Paul Jaccard</a>, originally giving the French name <i>coefficient de communauté</i> (community coefficient), and independently formulated again by T. Tanimoto. Thus, it is also called Tanimoto index or Tanimoto coefficient in some fields. </p>