Diaper and Beer

From WSJ:

Tesco's computers often turn up counterintuitive results. Shoppers who buy diapers for the first time at a Tesco store can expect to receive coupons by mail for baby wipes, toys -- and beer. Tesco's analysis showed that new fathers tend to buy more beer because they are home with the baby and can't go to the pub.

Detailer can be founded in a blog called Data Doghouse.
Giving causation to the correlation given by the statistics is quite interesting:
More interesting and probable OR people can do is the following:
We have N items with correlation matrix, and we want to put them in the shelf togather to gain maximum profit. It is quite similar to the facility layout problem. And we may also hope to change the layout as little as we can, since the customer use to current layout.