(FORTUNE Magazine) – When Alan Greenspan told Senators in early March that "the recent evidence increasingly suggests that an economic expansion is already well under way," it wasn't exactly news to economic forecasters and others who pay close attention to indicators. Evidence had been accumulating through January and February that the recession--if not over already--was likely to be shorter and far less severe than many had feared. Way back in early January, 90% of the forecasters polled by Blue Chip Economic Indicators predicted it would be over by April. Hardly a week has gone by since without the release of yet more data confirming their optimism. By early March, the evidence of the economy's strength was conclusive: GDP grew 1.4% in the fourth quarter--far higher than the 0.2% initial estimate--and the economy added 66,000 jobs in February, the first increase since July.

The Fed chairman's remarks made headlines as usual but were especially notable because his picture of a recovering economy was so at odds with the pessimistic readings featured in many newspapers over the past few months. Some of the media's most prominent pundits and journalists seemed particularly eager to refute the idea that the recession might be short and shallow, and reluctant to change their view as the data came in.

There are two reasons for this--one political and one institutional--and we'll get to them in a bit. But first a few examples:

When Treasury Secretary Paul O'Neill said after Sept. 11 he wasn't certain the economy was headed for recession and that the stock market might even bounce back over the next 18 months, he was derided. A New York Times editorial harrumphed that it was "not useful for the secretary to try to influence the markets with empty cheerleading and predictions of imminent upturn." The media were more in tune with Joseph Stiglitz, chairman of the Council of Economic Advisers in the Clinton Administration, who wrote in the Washington Post that he saw "the inklings of the downward spiral that was part of the Great Depression of 1929" and worried that "the U.S. economy will sink deeper into recession, and the rest of the world with it."

By Christmas, it was pretty clear to everyone that 2001 was not 1929. Most economists were already predicting the recession's imminent demise. But some media commentators were still dubious. On Jan. 9, Robert J. Samuelson warned Washington Post readers, in a column headlined economic dreamland, that they should "treat the recovery forecasts with skepticism."

Even in late February, two weeks before Greenspan wrote the recession's epitaph (and, to be fair, before the final burst of bullish economic indicators), some in the media had a hard time letting go. On Feb. 22, Paul Krugman, in his New York Times column, argued, "Both the Administration and many business leaders have taken a modest improvement in economic indicators as proof that the economy is poised for a full recovery. They could be right--but don't count on it." Two days later, New York Times staff reporter Louis Uchitelle began his Economic View column with "Skepticism about the economy is becoming harder to sustain. The latest statistics are too hopeful." But by the end of the column he had found a way to sustain his skepticism anyway, concluding--as had Krugman--that "maybe, instead of recovery there will be a second dip into recession."

The political explanation for the media's predisposition toward pessimism is this: As long as there's a recession, there's trouble for the Bush Administration, since whatever party holds the White House tends to get credit or blame for the state of the economy. Joseph Stiglitz is a vehement critic of Bush's policies; Paul Krugman, a downright splenetic one. Both of their aforementioned articles drip with disapproval of Bush and his policies. While it's possible the two might be as bearish about the economy if the current President's name were Gore instead of Bush, it's impossible to imagine.

Such political animus is in fact rare in financial journalism. The articles cited above by Samuelson and Uchitelle, for instance, are long on skepticism but devoid of Bush bashing. The more important and widespread reason for the media's pessimism is that journalists have every incentive to accentuate the negative. Media organizations prize skepticism: Pollyannas are frowned upon; Cassandras get promoted. Even Chicken Littles are tolerated, as long as they come up with hot copy. Why? Bad news sells. Just as a forecast like HURRICANE THREATENS WASHINGTON D.C. gets more viewers than one saying STORM MAY PETER OUT OVER CAROLINAS, a headline that says IS THIS ANOTHER GREAT DEPRESSION? will sell more papers than RECESSION MAY NOT BE SO BAD.

ROB NORTON, a former FORTUNE executive editor, is a freelance writer, editor, and consultant in New York City. He can be reached at rob@robnorton.com.