Data Mining: How Companies Now Know Everything About You
Time, By Joel Stein, Mar. 10, 2011
In the past few months, I have been told many more-interesting facts about myself than my Social Security number. I've gathered a bit of the vast amount of data that's being collected both online and off by companies in stealth - taken from the websites I look at, the stuff I buy, my Facebook photos, my warranty cards, my customer-reward cards, the songs I listen to online ...
Google's Ads Preferences believes I'm a guy interested in politics, Asian food, perfume, celebrity gossip, animated movies and crime but who doesn't care about "books & literature" or "people & society." (So not true.) Yahoo! has me down as a 36-to-45-year-old male who uses a Mac computer and likes hockey, rap, rock, parenting, recipes, clothes and beauty products; it also thinks I live in New York, even though I moved to Los Angeles more than six years ago. Alliance Data, an enormous data-marketing firm in Texas, knows that I'm a 39-year-old college-educated Jewish male who takes in at least $125,000 a year, makes most of his purchases online and spends an average of only $25 per item.
... Each of these pieces of information (and misinformation) about me is sold for about two-fifths of a cent to advertisers, which then deliver me an Internet ad, send me a catalog or mail me a credit-card offer. This data is collected in lots of ways, such as tracking devices (like cookies) on websites that allow a company to identify you as you travel around the Web and apps you download on your cell that look at your contact list and location.
and Joel Stein conclusion:
Oddly, the more I learned about data mining, the less concerned I was. Sure, I was surprised that all these companies are actually keeping permanent files on me. But I don't think they will do anything with them that does me any harm
The article also mentions other companies which provide personal information: