Andrew Pole, a statistician for Target, shared this eye opening story in an interview with the New York Times:

    A Minneapolis father was shocked when he discovered that his high school daughter was pregnant, and even more surprised to find out that Target knew before he did. When the company sent coupons for diapers and other baby necessities to his house, he called the manager of his town's store irate at what he saw as encouragement for his daughter to get pregnant.

   The manager apologized, but when he called back a few days later to apologize again, it was the father who was remorseful.

   "I had a talk with my daughter....she's due in August. I want to apologize," he said.

   So how does Target know details about its customers that even loved ones are unaware of? They assign every shopper a guest ID that records what they purchase.

    “If you use a credit card or a coupon, or fill out a survey, or mail in a refund, or call the customer help line, or open an e-mail we’ve sent you or visit our Web site, we’ll record it and link it to your Guest ID. We want to know everything we can,” said Pole in the same New York Times interview.     Also linked to that ID is detailed demographic information-your age, marital status, salary, credit cards, etc. Target can purchase additional data like your ethnicity, job history, political preference, and even which brands of coffee you favor.

   All of this info is then turned over to statisticians like Pole, who analyze it and predict your shopping habits, which can be very telling. For instance, analysts noticed that women on the baby registry bought bigger quantities of unscented lotion than other shoppers. They also noticed that in the first 20 weeks of pregnancy, women stocked up on supplements like magnesium and zinc.

     Companies like Target use these patterns to try and hook parents-to-be and make them long term customers.

   “We knew that if we could identify them in their second trimester, there’s a good chance we could capture them for years,” Pole said. “As soon as we get them buying diapers from us, they’re going to start buying everything else too." 

   Pole was later told by superiors to stop talking to the press.