The following video is from Tuesday's Digging for Value, in which host Alison Southwick, Motley Fool Senior Analyst Michael Olsen, and fool.com contributor Tyler Crowe dive deep into top stories for today's energy sector investors.

In this segment, Michael takes a look at three natural gas exploration and production companies -- Range Resources (NYSE:RRC), Ultra Petroleum (OTC:UPL) and Southwestern Energy (NYSE:SWN) -- and determines which one is the best buy, the biggest sell, and the one that might want to keep in your portfolio for a little while longer.