The Purdue industry clusters were created through a joint project between Emsi and the Center for Regional Development at Purdue University. The clusters can be found by clicking Groups in the header bar and selecting Industry Groups, then Template Groups.
Clusters are groups of interconnected industries that typically purchase from one another or otherwise benefit from being nearby each other. Many different definitions exist for different clusters, and we encourage our clients to use their local knowledge when doing cluster analysis. The Purdue clusters can be used as-is, or you can create a new group based on a Purdue cluster and modify it to suit your local needs.
See this article for more information on modifying template groups.