(FORTUNE Magazine) – EVER NOTICE HOW, when you are reading the business press, a few well-known security analysts keep popping up and getting quoted as authorities? Like Wolfgang Demisch in articles about aerospace. Or Hercules Segalas in stories about household products. Who are these experts anyhow? And why do we keep hearing from them and not somebody else? Disarmingly pretty, charming, and cheerful, auto analyst Maryann Keller, 42, is a member of this elite circle of oft-quoted Wall Street figures who command something akin to celebrity status (for others, see box). They are prized not only for the quality of their research on stocks and industries, but also for their prominence, which helps keep their firms' names fixed in the minds of prospective clients. Other analysts may be just as bright, but the quoted ones tend to be the most highly paid, drawing salaries of up to $500,000 a year. The most visible of this group, Keller is the first auto analyst many reporters turn to when they want a fix on a development in the industry. In the days after automakers launched their latest round of low-cost financing, for example, she appeared on four national television shows -- Good Morning America, Nightline, the CBS Morning News (twice), and the MacNeil-Lehrer Report -- plus two local TV news shows and a radio talk show. Keller also answered a barrage of telephone inquiries from newspaper and magazine reporters. The demand for her views is all the more remarkable given that for the past three years she was not even officially a security analyst, having left that job at the Paine Webber brokerage house. For most of the time since then she managed money for individuals and institutions at a small New York firm, Vilas-Fischer Associates. She only recently resumed her career as an analyst when she moved to another small firm, Furman Selz Mager Dietz & Birney. Her celebrity reaches far beyond her employer's. Part of Keller's appeal is that she has all the attributes of a media star, including a lively and gregarious personality and a gift for delivering opinions laced with sardonic humor -- in other words, she's quotable. But behind the quotes is a firm grasp of the industry's nuts and bolts. A hands-on analyst, Keller regularly visits assembly and parts plants around the world. She knows the names and functions of the tools used to build cars, and she never misses an opportunity to drive a new model. Just as important is what even fellow analysts call her unmatched global view of the industry and ability to spot trends. Eighteen months ago Keller was the only well-known analyst forecasting overcapacity in the U.S. for 1986, which she said would lead to widespread price cutting. Now General Motors, trying to work off bloated inventories, has forced a round of record low-interest financing, and the accepted wisdom in the industry is that Detroit has the capacity to produce over a million more vehicles a year than it can sell. Some analysts, understandably wrapped up in serving their clients, spurn calls from reporters. But Keller does not begrudge the time she spends talking to the press. ''It's a quid pro quo relationship,'' she says. While half the calls she receives are routine, Keller estimates that 15% or so hold some surprise: ''A journalist from a small-town newspaper will call me with a rumor that the car factory there is closing. All of a sudden I smell news.'' The rest of the calls are from experienced reporters who are writing about complicated or thought-provoking issues, such as the putative prejudice of Japanese auto manufacturers against U.S.-made car parts. Those calls, she says, help her structure her own thoughts on a subject. By Keller's account, there was little in her childhood to presage celebrity status. ''I was a wallflower, far on the outskirts of the in crowd,'' she recalls. ''Nobody saw greatness in me when I was in school.'' She grew up as Maryann Katula in the chemical factory town of Perth Amboy, New Jersey, about 30 miles south of New York City. Her parents, now retired, both worked. Henry Katula was a factory hand at National Lead Co., and his wife, Helen, was a nurse. There wasn't much extra money for entertainment, so Maryann would take her younger sister, Joann, to the library every week. The Katula sisters would check out four books each, the limit, and complete each one. ''Maryann always loved to learn,'' says Joann, now a public school teacher in New Jersey. ''She thought languages were wonderful, and she would teach me words just because they were fun to know. She memorized half of the Canterbury Tales.'' Joann would ask for dolls at Christmas; Maryann would ask for a chemistry set. By the time she turned 15, she was toiling at least 20 hours a weekend as a volunteer auxiliary nurse. At 16 she quit that and went to work after school slicing bread in a bakery. ''Wednesday was my fun day because we dipped cookies,'' she recalls. Every Friday she banked her paycheck, saving the money for college in hope of becoming a chemist. At the start of her junior year in high school, Keller says, she had a ''big fight'' with her father because he wanted her to fit a typing class into her schedule. ''Risk-averse, he thought I should learn to be a secretary as a fallback career,'' she explains. But with a $400 scholarship and her savings, Keller commuted to Rutgers University in nearby Newark, graduating in 1966 with a B.A. in chemistry. In 1968 she joined Celanese Corp. to analyze possible acquisitions. Says her former boss, Joseph F. Dash, now a senior vice president and general manager at CBS Records: ''I knew I wouldn't be able to hold her long because she was too talented.'' On lunch breaks Keller went next door to Merrill Lynch to watch the stock quotes and became fascinated with this glimpse of the market in action. In 1970 she left Celanese for what turned out to be a brief fling in the corporate finance department of Donaldson Lufkin & Jenrette. ''I hated it,'' she says. Told she would be an analyst, she wound up working as a statistical assistant doing, as she puts it, ''grunt work.'' She returned to Celanese, but only briefly. A friend who had left to join a brokerage house as an analyst persuaded her to give Wall Street another shot. KELLER TOOK the $17,000-a-year auto analyst slot at the Kidder Peabody investment firm, becoming the first woman to follow Detroit. No expert then, ! she did not know that the DeSoto nameplate had been dead for a decade. But she jumped in with enthusiasm and with a burning desire to be recognized as the best in her business. As she identified it, recognition meant getting onto Institutional Investor magazine's annual listing of the top analysts. ''When I first became an analyst, I wondered how I would ever make the list,'' Keller reflects. ''To me it was like winning the Oscar and the Emmy simultaneously.'' Three years after she hit the Street at age 29, Keller landed on the list as a runner-up. In 1979 she swept past her male competitors to be ranked the No. 1 auto analyst in the U.S. A year later she moved from Kidder Peabody to Paine Webber because, she says, it was a smaller, less bureaucratic operation. She held the title for four years until she left Paine Webber. Keller distinguished herself partly with her reports. Most analysts were content to crunch automakers' quarterly numbers and look for omens in ten-day sales figures. Keller added critiques of manufacturing technologies and analyses of industry trends. In 1973, for example, as Detroit was trying to come to grips with the oil shock, Keller spent five months researching the merits of six alternative engines, ranging from the turbine to the Stirling engine, and picked the diesel as the most likely to succeed. ''People thought I had grease under my fingernails after that,'' she says with a bewildered look. Some of her efforts enraged people in the industry. In a 1975 report on materials automakers would be using as they tried to make cars lighter and more efficient, she predicted that the amount of die-cast zinc, then used mainly as a base for chrome trim, would drop from about 34 pounds per car to 16 pounds by 1980. Miffed, the Society of Die-Cast Engineers invited her to a meeting where they challenged her estimate. But Keller stood firm, telling the engineers, ''Zinc is dead for cars.'' (The typical 1986 U.S.-made car contains 19.7 pounds of zinc die castings.) The controversy only pleased Keller. ''There are aspects of this business that are slightly theatrical,'' she admits. ''I could have written nice little reports and, maybe, eventually have been noticed. But since I wanted to distinguish myself early on, I had to create attention so that money managers would put my report on top of the pile.'' Keller further distinguished herself as the first analyst to spot the growing importance of the Japanese auto industry. In the early Seventies the Japanese were just beginning to set up full-scale sales organizations in the U.S., and none of Keller's rivals at other firms had paid them much attention. ''But when I began talking to Toyota, Nissan, and Honda, I realized I was on to something.'' The Japanese were hiring experienced sales executives from U.S. automakers and making plans to work harder than Detroit at pleasing customers. Keller concluded that they had the power to seriously challenge Detroit's dominance. She went on to visit virtually every car market in the world, including Brazil, Mexico, and Korea, before the pack got there. Stellar though it is, Keller's record has not been flawless. As a stock picker, she missed the great opportunity Chrysler offered in 1982, arguing for GM instead. ''Chrysler was a disaster financially, and I believed that GM, with all its financial power, would prevail,'' she says. ''After all, how could a company that has everything going for it blow it? It was the one time in my life where I let the numbers rule my judgment. I will never make that mistake again.'' And the U.S. auto market has not suffered as drastically as she predicted it would early in 1985, because she foresaw an end to the self- imposed Japanese export quotas and a subsequent flood of low-priced cars. Keller still thinks a flood is inevitable, though, as more and more nations build cars for export. Three years after she joined Paine Webber she startled Wall Street by resigning and moving to the relatively obscure VilasFischer. She was earning close to $300,000 a year, and several other firms were offering her more. But according to Eli Lustgarten, a vice president at Paine Webber who worked closely with Keller, ''Maryann was suffering from burnout. All the good analysts are workaholics, but she tended to take being a workaholic slightly to the extreme.'' At the same time, her 15-year marriage to lawyer Arthur Keller was collapsing. Maryann, who says only that she needed a new challenge, threw herself into her money management job at Vilas-Fischer. But she could not stay away from the auto business. She continued to take calls from the press, and she started a monthly newsletter on industry trends for institutional and corporate subscribers. Keller had taken a pay cut to join VilasFischer, expecting to become a stockholder within a year. Shortly after she came aboard, however, Vilas- Fischer sold out to a British insurance company. The new management did not proffer her any stock. ''I felt I had been misled about my future,'' she says. ''They sold the company right from under me.'' Vilas-Fischer says that Keller is ''a very competent and hardworking lady, but because of her high profile in the auto industry, it was impossible for her to use her time as her own.'' Though she could have had her pick of most major Wall Street firms, Keller puzzled her peers once again by moving to Furman Selz, a respected but small full-line brokerage firm. To Keller, however, smaller is better. ''You tend to have high-quality people in a small firm, because there is no room for anyone who isn't,'' she says. And Furman Selz has given her carte blanche to manage money and dabble in investment banking as well if she wishes. Keller is making her mark as a money manager, though she does not exude the same confidence on the subject that she does when she talks about cars. Three- quarters of her clients, including both institutions and individuals, followed her from Vilas-Fischer to Furman Selz. Frederick J. Mancheski, chairman of Echlin Inc., an auto parts manufacturer, uses a dozen money managers to run his company's portfolio. Keller, he says, has ''done better than most even though she has tough competition.'' BUT THERE is little doubt about the activity closest to her heart. Keller has become a sage of sorts to the auto business, a role she clearly enjoys. ''The recognition I'm getting now is much more valid than Institutional Investor because it is coming from the auto industry, not from the investment community,'' she says. She speaks more and more often to groups of dealers, suppliers, and manufacturers. ''Her presentations provide us with a point of view that sometimes can't be developed inside a company,'' says Fredrick Bolling, director of Ford's manufacturing development center. That is putting it mildly. At a recent Oldsmobile dealers' symposium she blasted GM for ''excessive spending, generic advertising, and failure to reduce the ranks.'' Though GM has only 43% of the market, she added, it is staffed to handle 50%. The dealers loved her candor. One came to her table afterward and said, ''Maryann, you are just a jewel. If I had any money, I sure would let you handle it.'' Two years ago Keller married Korean businessman Jay Chai, 52, a star of the auto industry in his own right. As executive vice president of the large, publicly held Japanese trading company C. Itoh & Co., he has arranged most of ( the major joint ventures between U.S and Japanese auto companies, including the GM-Toyota deal. Chai, divorced for nearly 15 years, had been a single parent with three children -- two sons and a daughter, ages 19 to 24 -- when they married. Keller's presence has changed the Chai household dramatically. ''My father is a different man,'' says Eleanor Chai, a vivacious 19-year- old third-year student at Oxford University. ''He laughs more and he's not as tense.'' After marrying Chai, Keller sat the children down and without talking to her husband in advance asked if she could legally adopt them. ''I felt like crying,'' says Julius, the older son. ''Her offer was so sincere that we knew she really cared.'' Keller delights in domestic details and brings as much energy to the family home in suburban Scarsdale, New York, as she does to work. ''Our life is humdrum,'' she says happily. She spends evenings and weekends cooking, gardening, decorating, or shopping for the kids. At night before going to bed, Chai sometimes helps Keller translate Japanese annual reports. Since Keller loves to cook, most of the family's entertainment centers on food. On Friday nights she and Chai shop together for groceries at the local Food Emporium supermarket, achieving another kind of celebrity. ''We are the only interracial couple, we have the heaviest shopping cart, and I have more coupons than any other customer,'' she says. Keller clips coupons every Sunday morning, sorts them by aisles in the supermarket, and organizes them in plastic bags. She was irate a few weeks ago when the Food Emporium reorganized a few aisles, throwing her system temporarily out of kilter. Having a big family has created what she calls ''a scheduling phenomenon,'' but Keller seems in no mood to cut back. In particular she is not about to withdraw from her role as the sage of the auto industry. Though the phrase is usually used by Detroit traditionalists to describe each other, it applies also to the woman from Perth Amboy, New Jersey: She has gasoline in her blood.