According to Herbert J. Gans, "the most relevant and interesting news most people see is the weather report. It is the same for everybody and it tells them something useful-what to wear to the office."

In comparison, he believes, most of the news that comes out of Washington is uninteresting and useless: "Sometimes the national media are almost a sort of newsletter for people in government.

"What the news audience wants and needs is one of the great unanswered questions of our time," he says, "but it probably doesn't need national news as often and as steadily as it gets it.

"I suspect that the public doesn't want to be as informed about Washington as it is, and this accounts for a lot of the showbiz aspect of news, the dramatization of stories."

Gans is a sort of Margaret Mead of big-time journalism, an intrepid researcher who lived among the little-known tribes who produce the news for NBC and CBS, Times and Newsweek, observing their New York village life for months on end, analyzing the folkways, taboos and curious rituals that result in brightly wrapped bundles of news.

Gans has packaged his findings in a book called "Deciding What's News," which examines the selection process by which thousands of potential stories are reduced to the few that reach print or picture tube. He finds much wrong with the process. That is in the Gans style.

Despite his established reputation as a social critic, Gans says he is not national news: "Most national news is generated by the 'knowns,' a few hundred people who appear in the media again and again while the 'unkowns' make it only when they are involve, in something violent or very unusual, or when their opinions are lumped together in a survey.

"I am definitely an 'unkown'; you would have to take 30 seconds to explain who I am, and that can kill the story. I don't know of any sociologist whom the national media would consider a 'known.'"

In fact, it takes more than 30 seconds. Gans was born in Cologne, Germany, in 1927 and came to the united States in 1940-not long before that kind of trip became impossible.Educated at the universities of Chicago and Pennsylvania, at first he was interest in journalism but decided instead to become a sociologist. In that profession, he consistently has made waves.

His earlier books include "Popular Culture and High Culture," which challenges stereotypes in the values of commercial enterainment; "The Urban Villagers," which debunks middle-class views of the poor; "The Levittowners," which explodes popular myths about suburbia; and a number of books on urban planning that contend, for example, that planners should be oriented less toward architecture and more toward the needs of the people who will be using it.

The new book shows Gans hasn't given up his interest in journalism, though it lay dormant for quite a while.

"It began when I was working in Levittown, attending public meetings," he explains. "They did'nt have a place to put a sociologist, so I sat with the journalists, and I began to notice that what a journalist considers important is not the same as what a sociologist considers important. So I began to study these contrasting value systems."

He has been working on the book since 1964, but it arrives in the middle of a booming post-Watergate national interest in the news media. "I was working on the book long before Walter Cronkite became 'the most trusted man in America,'" Gans says.

"Deciding What's News," however, is addressed to a much smaller readership than "The Camera Never Blinks" by Dan Rather (who is interviewed in the current Playboy) or even "The powers that Be," by David Halbestam. And despite his often ponderous academic language, Gans is far from complacent about his subject.

He thinks national news should be more useful to the people who receive it. Washington news, for example: "The country would not totter if we didn't know what the president did today, particularly the ceremonial functions which get so much attention.

"A lot of Washington news is reported because it is personally relevant to the audience. In order to vote once every four years, you don't need much national news. If you can't really participate in the government, if you can't affect its decisions, why bother to read about it?"

The book examines the assumptions that Gans believes underlie the selection of national news and color its reporting - that capitalism is usually a benign system, that virtue resides in small towns, that American foreign policy is essentially altruistic, that "welfare cheaters" are a continuing menace, and many others.

"Some of these values are out of touch with reality," he says, "but values by definition are out of touch with reality. Ask people where they would like to live, for example, and what they tell you, in effect, is a 5-acre farm near a subway stop.

"The implicit values of national-news reporting are not distinctively journalistic - otherwise, the journalists would be talking to themselves. And fortunately, people don't take the news media as gospel."

Gans believes the news is produced by an elite group, particularly in the case of the news magazines. "now that they have a mass audience, the newsmakers should expand their coverage, but they are still dealing with an elite.

"The upper middle class is considered newsworthy. The lower classes are not newsworthy unless they are making trouble. Domestic news is supposed to be about America, but it is actually about a very thin slice of America.

The book does not discuss newspapers, which Gans feel have somewhat different readership and priorities.

"National journalists are more protected from pressure that those in a small town," he says, "and the local newspaper has more space than the national media - a bigger 'news hole,' as they call it.

"With a bigger news hole, the rules on what is considered news can be relaxed a bit - but there have to be rules, people can't really function without them. And the rules are likely to be, to some extent, out of touch with reality.

His suggested solution to that problem is to establish a national fund such as the National Endowment for the Humanities, to subsidize news organs for segments of society, such as the lower middle class, which he feels are not being served adequately.

If you wanted to cover lower middle class people, you would have to set up new structures and rules and increase your news sources, and I don't think it could be done without government help free of government interference.

"Perhaps this idea is also out of touch with reality, but I would like to see it tried." CAPTION: Picture 1, Herbert J. Gans; Picture 2, no caption