How Cambridge Analytica hijacked 50 million Facebook profiles
https://www.theguardian.com/technology/2018/mar/17/facebook-cambridge-analytica-kogan-data-algorithm
How Cambridge Analytica turned Facebook likes into a lucrative political tool
The algorithm used in the Facebook data breach trawled though personal data for information on sexual orientation, race, gender and even intelligence and childhood trauma
Carole Cadwalladr and Emma Graham-Harrison
Sat 17 Mar 2018 09.02 EDT
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The academic (Aleksandr Kogan) had developed a Facebook app which featured a personality quiz, and Cambridge Analytica paid for people to take it, advertising on platforms such as Amazons Mechanical Turk.
The app recorded the results of each quiz, collected data from the takers Facebook account and, crucially, extracted the data of their Facebook friends as well.
The scale of the data collection Cambridge Analytica paid for was so large it triggered an automatic shutdown of the apps ability to harvest profiles. But Kogan told a colleague he spoke with an engineer to get the restriction lifted and, within a day or two, work resumed.
Within months, Kogan and Cambridge Analytica had a database of millions of US voters that had its own algorithm to scan them, identifying likely political persuasions and personality traits. They could then decide who to target and craft their messages that was likely to appeal to them a political approach known as micro-targeting.