With 3,600 stores in the United States and roughly 100 million customers walking through the doors each week, Wal-Mart has access to information about a broad slice of America - from individual Social Security and driver's license numbers to geographic proclivities for Mallomars, or lipsticks, or jugs of antifreeze. The data are gathered item by item at the checkout aisle, then recorded, mapped and updated by store, by state, by region.
By its own count, Wal-Mart has 460 terabytes of data stored on Teradata mainframes, made by NCR, at its Bentonville headquarters. To put that in perspective, the Internet has less than half as much data, according to experts.
Like last week, this week again I went shopping at Wal★Mart. I was talked into shopping there for a few weeks just to get a feel for how much money we won't spend there, as apposed to Publix. Yes, we're evil for doing it, and articles like the above don't make it any easier to do.
It's also amazing the amount of data they have, and how they can pour through it. Privacy and Big Brother issues aside, it is fascinating that they are able to data mine that much data. Who would have thought that Pop-Tarts and beer are big sellers prior to hurricanes? And how do you come up with the queries to find out such information?
But least you think that all that data Wal★Mart has can only be used for evil:
STILL, as Wal-Mart recently discovered, there can be such a thing as too much information. Six women brought a sex-discrimination lawsuit against the company in 2001 that was broadened this year to a class of about 1.6 million current and former female employees. Lawyers for the women have said that Wal-Mart has the ability to use its human-resources database to calculate back pay for the plaintiffs as well as to determine whether women were fairly promoted and paid. The judge hearing the case, which is pending in a federal court in San Francisco, has agreed.
The database is unusually detail-rich, said Joseph Sellers, a lawyer for the plaintiffs. “They've put into their work force database the information that bears on virtually every facet of compensation,” he said. “They have performance reviews, along with seniority, the time spent with the company, which store they worked in. So you can compare people working in the same store, to measure whether men and women are paid differently.”