Over the past two days, 80 new members of the President's Advisory Committee for the Kennedy Center have been feted with a cocktail party, a lucheon, a keynote address by Center board vice chairman Sen. Charles Percy (R-Ill.), and talks by program heads including Martin Feinstein and Archie Buffkins, consulant on minority affairs.

But after all the attention, most of the newly assembled members were still uncertain yesterday about exactly what they were supposed to do. "We weren't quite sure what our mandate was to be." said one.

No one seemed to know exactly how the members were chosen, either -- except that such decisions came from the president's office. And it was still undecided at yesterday's orientation sessions how often the group would meet.

One thing is sure -- they have no control over what happens at the Kennedy Center. "They are to consult with and advise trustees," said Robert I. Millonzi, cochair of committee, a New York attorney and a former trustee of the Kennedy Center. "They'll make suggestions primarily as to how the Kennedy Center can do their national outreach programs."

The committee is a geographic, racial and sexual cross-section of people prominent in the arts in their local areas.

In his keynote speech, Percy encouraged committee members to make suggestions on programs that could help promote the "cultural diversity" of the Kennedy Center. One member, Edyth Harrison, founding president of the Virginia Opera Association, promptly raised her hand to ask how they could make suggestions. Cochair Elizabeth Petrie, vice president of the Philadelphia Museum of Art, said the subject would be discussed later.

"I was a little annoyed," said Harrison later, "that the question wasn't answered so quickly. If we're talent scouts, what's the procedure?"

"The obligation of a national cultural center," she said, "is to bring the finest performing groups from around the country that are not in major cities. We're not giving those groups an opportunity yet."

"I'd like to see the Center promote folk music in educational programs around the country," said Paul Halpern, a music instructor at the University of Oregon. "The average person in Oregon, when asked for money for the Kennedy Center is going to say, 'Sure -- so socialites can go to the Opera.' But if they can see the direct benefits, they might be more willing."

The Center's Tom Kendrick said the members could work in their local areas to "speak out" for the arts, lobby Congress for more arts funding and be "a network source of funding for the Center if they choose."