Wrapping up three days of splendid seclusion, chief executives of many of America's biggest corporations still need convincing that the U.S. economy is firmly on the mend.

"We're all in a quandary. The economists are telling us there is more strength that we feel," CEO Glen Hiner of building materials group Owens Corning (OWC) said in an interview Friday. "We'd love to believe what the economists are saying."

Federal Reserve Chairman Alan Greenspan, as well as much of Wall Street's corps of economists, say the U.S. economy is either over or very nearly over the year-old recession that has brought layoffs, plant closings and other corporate cutbacks.

Recent statistical evidence, such as a sharp increase in estimates of late 2001 gross domestic product growth and a December jump in construction spending, bolster optimism about the economy returning to expansion.

But the chief executives meeting privately amid the palms and golf courses of the Boca Raton Resort & Club, an exclusive waterside complex south of Palm Beach on Florida's east coast, showed little enthusiasm for stepping-up hiring and investment spending anytime soon, according to participants.

New spending on equipment, plants, advertising and research by businesses will largely determine the vigor of any economic recovery, according to Fed officials. Greenspan and many others predict a slow, extended pickup in business activity.

MOOD CHANGED FROM LATE 1990s

"I think they're all very cautious," Scott McNealy, chief executive of network computer-maker Sun Microsystems Inc. (SUNW), said of the CEOs during a break from briefings by Harvard University's president, the U.S. commerce secretary and others.

"I don't see anybody who's running around, going 'Whee!' That was there a few years ago, but it's not there now," McNealy said.

David Komansky, the chief executive of brokerage Merrill Lynch and Co Inc. (MER), also reported that his peers at this year's Boca Raton meeting were wary of jumping too soon on business initiatives.

"I think most people agree that the economy statistically is well off the bottom, but yet most are still staying with a wait-and-see kind of attitude," Komansky told Reuters. "They're kind of reluctant to make any significant kind of commitments yet and I think there, too, it's a question of them gaining confidence going forward."

John Snow, chief executive of CSX Corp. (CSX), the eastern railroad and transport group, said the meals and briefings on the world's changing workforce and education yielded no sign of enduring boardroom pessimism.

"I think people generally feel the worst is over in this recession," Snow said during an interview.

Many CEOs interviewed outside the private events organized by The Business Council, an elite grouping of current and retired chief executives, said the U.S. recession was just another turn in the economic cycle and a chance for big companies to ready for the eventual improvement.

"I don't find any air of discouragement," David Goode, chief executive of railroad Norfolk Southern Corp. (NSC), said in an interview. "People are planning carefully for the uptick in the economy. People are making sure their businesses are working well."

The short-term caution among the company leaders was also evident in a survey by The Business Council of 75 sitting CEOs released Wednesday showing three-quarters believed the economy was still in recession.

But 77 percent saw the downturn ending this year and about half predicted the recession would be over by June 30.

The United States was, "not quite out of the recession yet, but there are some encouraging signs when you look at the fourth quarter figures, particularly sales figures, and the tremendous decrease in inventories that we saw," said Sidney Taurel, chief executive of drugmaker Eli Lilly and Co.