Interest rates, generally considered a key to the duration of the recovery, could be on their way up in the next year, a Reagan administration economist and a Wall Street financial analyst predicted yesterday.

William A. Niskanen Jr., a member of the Council of Economic Advisers, told a luncheon meeting of the American Club in Copenhagen that there is a 70 percent chance that rates will rise by about one percentage point and drop by as much as three points.

And influential economist Albert Wojnilower of First Boston Corp. told clients that rates have begun to move up and will continue their rise until the next recession sets in.

However, both said the movement of rates in 1984 could zigzag, depending on fiscal and monetary policy. Many economists have said interest rates should move down slightly next year from current levels.

"There is a potential for a big drop," Niskanen said. But the presidential adviser said he is "not entirely confident" of the chances for a decline because of the strong political pressures against cutting federal government spending.

"So long as the business upswing remains orderly, rates are apt to zigzag their way up only slowly and intermittently--say 1.8 percent per month on average," Wojnilower said.

He said that long-term and short-term rates "are likely to rise by about the same number of basis points, although the timing will not be identical due to erratic money supply fluctuations, Treasury financing efforts and so forth."

Wojnilower predicted that deposit institutions will bid up rates they pay on deposits, forcing up long-term rates "because buyers of new Treasury long-term issues will continue to insist on a sizable yield inducement."

In yet another statement concerning interest rates, Treasury Secretary Donald Regan said the government's fourth-quarter borrowing costs will probably be between $45 billion and $50 billion, short of the $60 billion to $65 billion originally predicted by the government.

The announcement, which spread quickly along Wall Street, had little impact, however, because many analysts already felt the administration's forecast had been too high.

"We have been stating we felt the financial needs would be about $50 billion for the fourth quarter," said Leonard J. Santow of Griggs & Santow Inc.

"It's good for the market," said Elliott Platt, economist with Donaldson, Lufkin and Jenrette. "It's a moderately positive development. The problem is, $45 billion to $50 billion is still a large amount by historical standards."

Regan said the lower borrowing costs were due to the increase in business activity. "We are collecting more money," Regan said. "At the same time, we're trying to hold down spending."

Santow agreed. The government "did better on receipts and individual taxes" than previously estimated, which could mean the government deficit could drop below the projected $200 billion mark, Santow said. "The improvement is better than the raw economic data would suggest."

Part of the increased taxable income that didn't show up in salary increase figures could be attributed to capital gains made in the stock and bond markets. "Maybe the economy is somewhat better than the economic numbers might suggest," Santow said.

Several words were dropped yesterday from a quotation attributed to Council of Economic Advisers member William A. Niskanen Jr. He should have been quoted as saying there is a 70 percent chance that interest rates will rise by about 1 percentage point and a 30 percent chance they will drop by as much as 3 points. Economist Albert Wojnilower of First Boston Corp. should have been quoted as saying that interest rates may rise 1/8 percent per month on average.