A day after one of the most volatile trading days in recent Wall Street memory, Bob Doll, chief equity strategist at Nuveen Asset Management, said the market may have found its bottom.

"There is a chance the bottom's in. I'm not going to say it's 100 percent but I can say it's at least 50 [percent]," Doll said in an interview Tuesday with CNBC's "Squawk Box."