The housing market is an example. The Fed, deciding last year that it needed to do more, began to buy mortgage bonds in an effort to drive down borrowing costs. The lower rates spurred a wave of refinancing and home buying. But now, as the recovery gains momentum and the Fed signals that it plans to pull back, interest rates are beginning to rise and mortgage refinancing is beginning to wane.

Mr. Bernanke said on Wednesday that the rate increases were a “good thing,” a sign that the economy is returning to health.

But Ian Shepherdson, chief economist at Pantheon Macroeconomics, said the Fed still runs the risk of withdrawing its extra support for the economy too soon.

“Later in the cycle, we will be happy to take that view too,” Mr. Shepherdson wrote Wednesday. “But not now, and it is very odd coming from a Fed chairman who has placed so much emphasis on the role of housing in the recovery. We do not think the market is yet ready to absorb higher rates.”

The Fed, in a statement released after the meeting of the Federal Open Market Committee, sounded notes of increased optimism about the economy, but unusually, the statement did not describe the bond-buying timeline. Mr. Bernanke said he had been “deputized” to share the details at the news conference.

The statement said that the economy was expanding “at a moderate pace” and that the job market was improving. Most significantly, it noted that risks to growth had “diminished since last fall,” an important assertion because the Fed has been trying in part to shield the economy from the consequences of reductions in federal spending. Those consequences have been milder than expected.

In a separate forecast released at the same time, Fed officials predicted that the unemployment rate would decline more quickly than they had projected, dropping to between 6.5 percent and 6.8 percent by the end of 2014. In March, they predicted that the rate would fall by the end of next year to between 6.7 percent and 7 percent.