[TristanDaCunha]

Disclosure: I worked at Cambridge Analytica.

Cambridge Analytica were accused of taking data mainly on what pages users 'Liked' - not private messages or news feed. (Unless you have a source?)

Obama campaign boasted about having access to the entire friends network. In other words, they know who each person was and what the connections between them were. Facebook openly said that they helped the Obama campaign get and utilise 100% of the friends network data on Facebook.

[loceng]

Fairly sure that's not anywhere near the whole picture of what CA was accused of? I thought CA ran surveys and from that data could make implications based on the friends and friends if friends of the person who took the survey?

[auganov]

My understanding is the quizzes were just viral Facebook apps to get API authorizations which back then let you download a lot of friends' basic data.

Simple scraping would get you a lot of the same data back then but it would be more involved and less solid legally. CA just figured out an easy way to do a huge scrape of Facebook.

I'd be surprised if many other organizations out there aren't sitting on similar datasets.

Even without asking any psychometric questions you could easily seed this through the dataset based on just a few examples or ground truths. This part seems rather unspectacular. With all the likes you can already tell who's alike. You just need to label the clusters.

CA's sell was this data would allow them to target super precisely and send different messages to different groups. But there's a big bottleneck at message creation. If you have 10 ads you can only target 10 groups uniquely. I'd be much more impressed if CA actually had software to manage ad creation, placement and performance tracking.

[_jal]

If that disclosure statement means what it is apparently meant to imply, it would of course be substantially more interesting to hear what you know, rather than talking about accusations, no?

But if you actually want a refresher, and for anyone else,

https://en.wikipedia.org/wiki/Cambridge_Analytica

[TristanDaCunha]

Well I'm not willing to provide any proof of my identity, so you have no reason to take what I say as legitimate. Indeed, I've seen lengthy posts of utter nonsense from others who claimed to work at CA.

Usually, even the generally available facts are a lot better than most people's understandings of the situation. For example, most people seem to think that this scandal proved that Facebook sell their user data, whereas it actually is alleged that CA took advantage of the well-documented public API that Facebook used to have, where any app vendor could download data on friends of friends who had given permissions to the app.

If you have specific questions, I would be happy to point you in the right direction.