The Associated Press reports:
To get an idea of the data Facebook collects about you, just ask for it. You’ll get a file with every photo and comment you’ve posted, all the ads you’ve clicked on, stuff you’ve liked and searched for and everyone you’ve friended – and unfriended – over the years.
But activity isn’t limited to pages or posts you like, comments you make and your use of outside apps and websites. “If you start typing something and change your mind and delete it, Facebook keeps those and analyzes them too,” Zeynep Tufekci, a prominent techno-sociologist, said in a 2017 TED talk .
And, increasingly, Facebook tries to match what it knows about you with your offline data, purchased from data brokers or gathered in other ways. The more information it has, the fuller the picture of you it can offer to advertisers. It can infer things about you that you had no intention of sharing – anything from your ethnicity to personality traits, happiness and use of addictive substances, Tufekci said.
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