What was going on when I was born?

A Surge in Inventories Manufacturers and merchants are restocking their warehouses and store shelves at a fast pace. Their willingness to increase inventories despite current high financing costs means they are confident they can sell these goods quickly and profitably. The buildup has been such that when the Government issues its report this Friday on February inventories, it will show a rise of at least eight-tenths of 1 percent, or double the January increase, said Edward E. Yardeni, chief economist at Prudential-Bache Securities Inc. Equally important, Mr. Yardeni noted, the inventory-sales ratio for February could rise to 1.33, from 1.30 in January. ''This means,'' he said, ''that many businesses are now more concerned about losing sales because of bare shelves than being caught with expensively financed goods, which was their costly experience during the recent recession.''

Americans working for the Central Intelligence Agency on a ship off Nicaragua's Pacific coast have been supervising the mining of Nicaraguan harbors in recent months, according to Reagan Administration officials and members of Congress. The sources say the mining operation marks the first time since the United States began supporting Nicaraguan rebels three years ago that Americans have become directly involved in military operations against Nicaragua. The actual placement of the mines inside Nicaraguan territorial waters, they said, is handled by an elite group of Latin American commandos who use small, high-speed boats to penetrate shipping lanes close to shore. 'Closer to Direct Confrontation' The officials said that unlike ground operations inside Nicaragua conducted by rebel forces, which American advisers monitor from Honduras but do not control, the planting of the mines in Nicaraguan waters directly involves Americans and is under their immediate control.

TRY to think of an office scene in a major modern American novel. Hemingway scarcely has one anywhere in his work. (He never used his famous brawl with Max Eastman in Maxwell Perkins's office as fictional material.) In ''The Grapes of Wrath'' and scores of other protest novels of the 1930's, the callous acts of bankers and businessmen are described, but we seldom see them committing the acts - or, in the case of ''The Grapes of Wrath,'' see them at all. In ''The Great Gatsby,'' Nick Carraway comes to the office of the racketeer Meyer Wolfsheim, only John Brooks , a staff writer for The New Yorker, is the author of two novels and much nonfiction about American business. to be rebuffed by a receptionist: '' 'You young men think you can force your way in here any time,' she scolded. 'We're getting sickantired of it. When I say he's in Chicago, he's in Chicago.' '' Wolfsheim does nevertheless appear and invites Nick into his office, but the ensuing conversation is entirely about why Wolfsheim can't go to Jay Gatsby's funeral. Carraway gets just about as close to actual business dealings (in this case, shady ones) as do most American fictional characters. When it comes to the moments that count from a business point of view, the door of the executive suite is usually closed.

The Rangers, who one week ago said that overcoming the Islanders would be an almost impossible mountain to climb, now stand only one victory from tossing the four-time Stanley Cup champions from the pinnacle of the National Hockey League. Led by Pierre Larouche's two goals, and another standout goaltending job by Glen Hanlon, the Rangers last night thrashed the Islanders, 7-2, at Madison Square Garden to take a 2-1 advantage in the three-of-five- game, opening-round playoff series. The series could end tonight in Game 4 at the Garden with a Ranger victory. Not since 1982, in a first-round series with the Pittsburgh Penguins, have the Islanders been in such a ''must-win'' situation. Since avoiding elimination that year, with a fifth- game victory over the Penguins, the Islanders have gone seven straight playoff series without entering a game in which they faced elimination.

Before any Oscars are handed out tomorrow night at the 56th annual Academy Awards, someone will walk out on stage and recite the voting rules. This tradition begain in 1970 when the FCC demanded it, and the Academy has gone out of its way ever since to get this part of the show over with fast. Last year, the actor John Moschitta breezed through it in 25 seconds - the length of one of his television commercials for a package delivery service. The Academy doesn't like to go into specifics about its membership, but every year when the nominations are released, surprising nominations and omissions raise questions about who is doing the voting. Many members of the Actors Branch, for example, haven't made a movie in decades. The Directors Branch, with Elaine May and Claudia Weill as its only female members, is virtually an exclusively male preserve. Who, in fact, are the 4,053 Academy voters and how do they vote? And do they all even bother to vote?

NEWARK A DRIVE to raise money to expand and renovate the Newark Museum - a plan that has lain dormant for 16 years - got under way last week, with state officials, business representatives and supporters of the arts calling the work a complement to the state's plans for urban economic rebirth and growth. The renovation, which involves four buildings of disparate architecture that have to be integrated schematically, has been designed by Michael Graves of Princeton, an architect with an international reputation whose other current projects include changes at the Whitney Museum of American Art in Manhattan. Addressing about 150 friends of the museum in the skylit central court, where some of the institution's better- known holdings in American art are being displayed, Governor Kean said: ''The way we value the arts - creations of the human mind and spirit - says a lot about our values as people.'' Later, the Governor, a former trustee of the museum, said that developments in the arts were creating the kind of public image needed for growth and new jobs in the state. He pointed to the George Street Theater in New Brunswick and the Walt Whitman Poetry Center in Camden as ''other catalysts of rebirth.''

Because of the Rev. Jesse Jackson's strong showing in the Democratic Presidential primaries, leaders of both parties are putting renewed effort into analyzing his potential impact on the Democratic National Convention and the general election. Mr. Jackson and his advisers said they would begin meetings this week to plan how the civil rights leader could play a key bargaining role at the convention in San Francisco in July. A 'Specific Agenda' Mr. Jackson said in an interview yesterday that he would arrive there with a ''specific agenda'' of issues and concerns. However, his main issues adviser, Ronald P. Walters, said there had Walter F. Mondale finished first as Wisconsin Democrats held caucuses amid much confusion. Page 36.

In the minds of most Americans, thatched roofs are for fairy-tale cottages. But in Britain and throughout Europe, this age-old method of roof construction has gained renewed popularity and respect because of its natural durability and old-fashioned beauty.

United States and Japanese negotiators reached agreement today on new export quotas that would allow American farmers to sell significantly more beef and citrus products to Japan. The American announcement of the accord late today came only hours after the talks seemed on the verge of collapse. The previous agreement expired last Saturday. United States negotiators here hailed the pact, which came after two and a half years of negotiations. To many in this country and in Japan, the talks had come to symbolize the larger differences on trade between the two countries.

-op apartment was having trouble sleeping at night because the elderly, bedridden and hard- of-hearing tenant upstairs kept his television blaring long past midnight. The family asked the board to intervene. Meanwhile, the owner of a Manhattan penthouse co-op was stirring up a buildingwide conflict because she maintained that the terms of her proprietary lease gave her exclusive rights to the roof. Far from being isolated incidents, stories such as these are becoming so common that the Council of New York Cooperatives, which represents more than 350 co-ops in the city, is exploring several conciliation programs designed to resolve such internal co-op disputes. In other instances, house regulations are being modified to try to forestall the most frequent types of conflict and independent mediators are finding a fertile new field for their services.

WASHINGTON E VER since the New Hampshire primary turned a relatively genteel race for the Democratic Presidential nomination into a street brawl, President Reagan has been doing as little as possible to divert attention from the Democratic candidates' slashes at each other. His campaigning for re-election has centered largely on the traditional appeals to business, ethnic and women's groups that marked his visit to New York City last week. But last week also brought an abrupt change in Mr. Reagan's broader strategy. Swinging at critics of his policies toward the Middle East, the Soviet Union and Central America, the President was on the offensive. White House officials billed it as an attempt to take a high institutional road, asserting that Congressional criticism of foreign policy was undermining American interests abroad. But its effect was to rupture what little civility was left in the foreign policy discourse and to raise questions about how much cooperation there can be in the months ahead.

D. W. GRIFFITH An American Life. By Richard Schickel. Illustrated. 672 pp. New York: Simon & Schuster. $24.95. By Peter Bogdanovich WHEN I asked Allan Dwan, the late pioneer picture maker who began directing in 1910 (and who continued into the early 60's), to describe in what ways he had been influenced by D. W. Griffith - who started making films only two years earlier - Dwan was typically blunt. ''We just went down to the nickelodeon to see what Griffith was doing,'' he said, ''and then we'd go out and try to do the same thing.'' Every director did. John Ford, arguably our greatest, began as a stunt rider for Griffith in the Ku Klux Klan chase scene in the controversial ''Birth of a Nation.'' ''I was the one with the glasses,'' Ford used to joke. Griffith's influence on Ford was not only apparent but acknowledged. Griffith, Ford would say, ''did it all.'' Even a film maker as temperamentally and artistically different from Griffith or Ford as Alfred Hitchcock tipped his hat to the father of the movies. ''A bit dated now,'' Hitchcock once told me, ''but it's certainly all there, isn't it?'' Still, today there is no director working who doesn't owe (consciously or not) some