Store manager Jenine Bryant scanned the entrance of the Best Buy, sizing up each customer who passed through. Just before noon, a blond woman in a fashionable white sleeveless shirt and flower-patterned pants wandered in unsteadily, fumbling inside her purse for a scrap of paper.

She looked at it, then looked up at the signs denoting how the store is laid out, and then she looked down and up again. Bryant recognized her immediately and rushed over.

The woman was a "Jill," code name for a soccer-mom type who is the main shopper for the family but usually avoids electronics stores. She is well-educated and usually very confident, but she is intimidated by the products at Best Buy and the store clerks who spout words like gigabytes and megapixels.

Best Buy Co. is trying to change that by giving her the rock star treatment at selected stores: Sending sales associates with pink umbrellas to escort the Jills to and from their cars on rainy days and hoisting giant posters in the stores that pay homage to the Jills and their children, who are shown playing with the latest high-tech gadgets.

Big chain stores used to be among the most egalitarian of places. They were aimed at the average person, the generic "shopper," without conscious regard to background, race, religion or sex. That is changing as computer databases have allowed corporations to gather an unparalleled amount of data about their customers. Many retailers, like Best Buy, are analyzing the data to figure out which customers are the most profitable -- and the least -- and to adjust their policies accordingly.

Express clothing stores no longer accept returns from those the company deems to be serial returners. Filene's Basement has even gone so far as to ban a few customers from its stores because of excessive returns and complaints.

Such endeavors have proved controversial, because the computer programs that try to determine a customer's true value are still a work in progress, with the potential to alienate as well as attract good spenders.

But inspired by Columbia University Professor Larry Selden's book, "Angel Customers and Demon Customers," Best Buy chief executive Bradbury H. Anderson is on a mission to reinvent how the company thinks about its customers. Best Buy has pared some less desirable shoppers from its mailing lists and has tightened up its return policy to prevent abuse. At the same time, it has begun to woo a roster of shopper profiles, each given a name: Buzz (the young tech enthusiast), Barry (the wealthy professional man), Ray (the family man) and, especially, Jill.

Based on analyses of databases of purchases, local census numbers, surveys of customers and targeted focus groups, Best Buy last fall started converting its 67 California stores to cater to one or more of those segments of its shopping population. It plans to roll out a similar redesign at its 660 stores nationwide -- including about 15 in the Washington area -- over the next three years. The Best Buys in the Springfield Mall, the Fairlakes shopping center and Potomac Mills, for instance, are being transformed into stores for Barrys, featuring leather couches where one might imagine enjoying a drink and a cigar while watching a large-screen TV hooked up to a high-end sound system.

The Santa Rosa Best Buy, Store #120, is a Jill store.

Pink, red and white balloons festoon the entrance. TVs play "The Incredibles." There is an expanded selection of home appliances as well as new displays stocked with Hello Kitty, Barbie and SpongeBob SquarePants electronic equipment. Nooks are set up to look like dorms or recreation rooms where mom and the children can play with the latest high-tech gadgets at their leisure. Best Buy has new express checkout lines for the Jills; store managers say anyone can use them, but if you are not escorted by a special service representative they can be easy to miss. The music over the loudspeakers has been turned down a notch and is usually a selection of Jill's favorites, such as James Taylor and Mariah Carey.

But who exactly is a Jill?

"She's very smart and affluent," said Best Buy employee Jenn Metzger.

"Jill is a decision maker. She is the CEO of the household," said Tony Sagastume, the general manager for the Santa Rosa Best Buy.

"Jill's children are the most important thing in her life," Bryant added.

According to the data Best Buy has collected, Jill shops a few times a year -- usually twice -- at an electronics store, but she usually spends a significant amount.

Since the redesign was rolled out in October, Jills have increased their spending at the Santa Rosa store by 30 percent, helping boost the store's revenue to what is expected to be $75 million to $80 million this year from around $50 million a year before the redesign and pushing its customer loyalty rating to among the top five in the country.

Nationwide, such "customer centricity" stores had an 8.4 percent increase in sales in the quarter ended May 28, compared with the same period a year ago, Best Buy executive John C. Walden said in June.

About 20 percent of the overhaul has to do with store merchandise, but the other 80 percent is more about the customer experience, said Susan Busch, a Best Buy spokeswoman. About a dozen of the Santa Rosa store's 210 employees are dedicated to what is known internally as the Jill segment team. To customers, this group is known as personal shopping associates, and its members wear pastels instead of the royal blue shirts that other salespeople in the store sport. They are stationed at an island smack in the center of the store decorated with fake purple flowers and stuffed animals.

"Is there anything special you're looking for today?" Bryant asked the blond woman.

"Oh, yes," she said, glancing down at the paper in her hand. "Playstation-2-Charlie-and-the-Chocolate-Factory?"

Bryant introduced the woman, Ann Facciano, 59, to another member of the Jill team, 18-year-old Jeremy Herman. Herman beamed at her and walked her over to the selection of games, pulled the appropriate box out of the stack, and then walked her back to the express checkout counter.

"Perfect!" Facciano exclaimed, admitting that she usually avoids Best Buys and asks her husband to come here whenever she needs something.

When Herman explained the store's new focus and handed her a card with his work e-mail address and a phone number for the specially trained Jill associates, Facciano squinted at the balloons and the new children's displays. "I guess I had better start coming in here more and figuring out what you have."

In the few minutes Herman had been helping Facciano, another woman in an almost identical crisp white shirt walked in, looking confused. Another Jill.

Bryant jumped in front of her. "Are you finding everything all right?"

"Uh, no," the woman said. "Uh, I have this Dell computer and . . . " Bryant smiled and nodded, and they were off.

Store manager Jenine Bryant explains how the Santa Rosa Best Buy has been redesigned to better serve soccer-mom-type shoppers.