Nouriel Roubini, the once obscure New York University economics professor who two years ago predicted the current global financial crisis and recession, said those who are turning bullish on the U.S. stock market need to reassess the data.Roubini told Bloomberg News he was "still quite bearish on U.S. and global equities." Despite losing much of their value already, Roubini thinks they could still lose another 15-20% before any recovery beginning towards the end of 2009.
Caveat emptor: let the (stock) buyer beware
The S&P 500 has fallen more than 40% in 2008, and with a forward P/E of about 12, one could make the case that stocks are at least approaching cheap levels, based on the post-World War II P/E average of about 17. Economist Richard Felson is not of that camp.
"Cheap compared to what? Compared to bull market high P/Es of 25 or 26, yes, but that assumes a) a return to GDP growth levels experienced before the recession hit; and b) that stocks won't drop to lower levels. You can't assume either, so Roubini's downside forecast may represent 'discretion being the better part of valor'," Felson said. "This is a risky time to own stocks or increase positions. Stocks could become much cheaper, particularly if the recession lasts into Q3 2009."
Investors have become accustomed to bull markets -- long periods of stock price appreciation, i.e. a rising stock market. That's been the norm since the start of publicly-traded stocks in the United States, and certainly a feature of markets in the post-1980 period. 
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