The superintendents and principals who administer the nation's public schools are an ingrown, self-satisfied group whose opinion of schools' performance is far higher than the public's, according to a survey released yesterday.

"What we have is a rather insulated bureaucracy of people who pretty much think alike {and} are very high on themselves," said C. Emily Feistritzer, director of the nationwide study, which was funded by the Department of Education. "The administrators . . . are overwhelmingly male, white, well-paid, and resistant to outside influence . . . . The phrase 'old boys club' has true meaning when it comes to the administrators of our public schools. I think they have to open their ranks."

According to the survey, conducted last fall, 87 percent of superintendents and 75 percent of public school principals say schools in their communities have improved in the past five years. By contrast, a Gallup Poll earlier last year reported that only 33 percent of public school parents and 25 percent of the general public share that view.

The survey reported that 96 percent of the superintendents are men, 97 percent are white and 92 percent are over 40 years old. Among principals, the survey said, 76 percent are men, 90 percent are white and 80 percent are over 40. Only about a third in either job have ever worked full-time outside education, it said, and virtually all have had teaching experience.

Feistritzer said almost all the superintendents and principals have bachelor's, master's or doctorate degrees in education, rather than training in other fields. Overall, 94 percent of both superintendents and public school principals say they are satisfied with their jobs.

"They're part of a closed system," Feistritzer said. "There's no difference in attitudes between school administrators in their 30s and their 60s."

Feistritzer is director of the National Center for Education Information, a private Washington-based group that publishes several newsletters and has issued reports on schools and teachers for the Carnegie Foundation and with government grants. She said a $97,928 federal grant financed the new survey.

Richard D. Miller, executive director of the American Association of School Administrators, disputed Feistritzer's interpretation of the survey results.

He said yesterday that school districts have employed increasing numbers of women and minority administrators and are seeking more. The opinion that schools have improved, he said, is based on rising test scores and stiffer curriculum requirements that the general public may not know about. "Maybe what the schools really need is better public relations," Miller said.

He said school administrators' attitude toward their profession is similar to that of doctors and lawyers toward theirs, and that professional training and teaching experience are necessary for effective school administration.

But Chester E. Finn Jr., assistant secretary of education for research and improvement, who called the report "deeply sobering," said "the problem with {the administrators'} homogeneity is their 'everything is okay' attitude . . . . It just isn't true."

Finn noted that the principals of many private schools, including some of the most prestigious such as Exeter Academy in New Hampshire, do not have teaching experience or education degrees. "Why shouldn't the public schools have the same options?" Finn said.

The survey was based on responses from 1,704 superintendents, 1,349 public school principals and 524 private school principals. It found 51 percent of the superintendents earn more than $50,000 a year, while the average salary of principals was $42,000.

Compared to the general public, both groups were more opposed to school busing for racial balance and to U.S. government involvement in local schools and more in favor of early sex education, the survey said.