The stock market has become overheated since exploding off its March lows and could be in for a strong correction, economist David Rosenberg told CNBC.
"It is overvalued by at least 20 percent," Rosenberg, formerly chief economist at Merrill Lynch and now with Gluskin Sheff, said in a live interview. "But it comes down to what your view in corporate earnings (is) going to be. By the time you're up 60 percent from any egregiously oversold low, you've already got the earnings recovery."
