From the archives of TiPWiki, the unofficial Duke TIP Wiki
A RAG (Resident Assistant Group, renamed Residential Activity Group after the switch from RA to RC) is group of TIPsters who live on the same hall. All members of a RAG are of the same sex.
This group is governed by an RC. At Davidson, Appalachian State University, Texas A&M, UGA, Trinity, Rollins, Austin College, Rice University, and the University of Kansas they are called RC Groups. RAGs attend meals together (the first two breakfasts and all dinners), and usually are the unit of grouping for campus-wide events like Casino Day, Treasure Hunt, etc.