A golden vein

摘要

In the old days, knowing your custom-Aers was part and parcel of running a business, a natural consequence of living and working in a community. But for today's big firms, it is much more difficult: a big retailer such as Wal-Mart has no chance of knowing every single one of its customers. So the idea of gathering huge amounts of information and analysing it to pick out trends indicative of customers' wants and needs-data mining-has long been trumpeted as a way to return to the intimacy of a small-town general store. BUI tor many years, data mining's claims were greatly exaggerated. Customer-loyalty cards, which allow retailers to gather information not just about what is selling, but who is buying it, sound like a great idea. Yet Safeway, a British retailer, eliminated its customer-loyalty card when it realised it was gathering mountains of data without being able to use it. Then there was the famous story that Wal-Mart had discovered that sales of nappies (diapers) and beer were highly correlated, as young fathers dropped in at its stores on their way home from work to pick up supplies of the former, and decided to stock up on the latter at the same time. Wal-Mart, the story goes, then put the two items side-by-side on its shelves, and sales rocketed. Alas, the whole story is a myth, an illustration of data mining's hypothetical possibilities, not the reality.