Stalk my pals on social media and you'll know that the next words out of my mouth will be banana hammock

Boffins reckon they can predict what you'll say based on your friends' activity online


The phenomenon of "prescient Facebook advertising", so beloved of conspiracy theorists who think social networks listen to your microphone, might instead simply be evidence of how good Facebook's algorithms have become.

That's one of the surprising hypotheses to arise from research by boffins from the University of Vermont and the University of Adelaide, published today in Nature Human Behaviour.

Speaking to The Register, co-author Lewis Mitchell of Adelaide University said the chief conclusion of the work he conducted with Vermont's James Bagrow and Xipei Liu related to how well individuals can be predicted not from their own posts, but those of their friends.

Analysing posts from as few as eight of your friends is enough to predict what you'll write next, with up to 64 per cent chance of success.

Mitchell told El Reg the research looked at a question relevant in a post-Cambridge Analytica world: how effective is deleting your account in protective privacy?

Not very much, the trio found. By focusing on people's networks of friends, their startling discovery was that close to 65 per cent of the time, with eight or nine friends' feeds to analyse, they could predict the next thing you would say.

The good news: that's not a permanent state of affairs. If you deleted your account, the quality of inference that can be made according to your (former) friends' posts will deteriorate over time.

"There's a recency effect," Mitchell said. "If you delete your account, the information will wash out, and the predictability about you from your friends' posts will eventually decay."

However, he said, the research clearly made the case that it's misguided to overemphasise individual responsibility for privacy. Privacy is clearly a collective responsibility.

"The responsibility lies with FB and Twitter, the social media platforms – they're the ones that have that network-level view, it's something the network has to grapple with."

Prescient advertisements

What's this got to do with those advertisements that creep people out by seemingly intruding on their recent real-life conversations?

Mitchell said work like his group's provides a theoretical underpinning to understand how good the "black box" of a social media algorithm can be.

"After this, I'm not surprised by the ability of Facebook to recommend ads as if they had the microphone turned on," Mitchell told The Register.

He said people are so predictable from their friends' posts, "you could conceivably build language models about the types of statements someone might make, and in principle use that for recommendations". ®

Similar topics


Other stories you might like

  • Prisons transcribe private phone calls with inmates using speech-to-text AI

    Plus: A drug designed by machine learning algorithms to treat liver disease reaches human clinical trials and more

    In brief Prisons around the US are installing AI speech-to-text models to automatically transcribe conversations with inmates during their phone calls.

    A series of contracts and emails from eight different states revealed how Verus, an AI application developed by LEO Technologies and based on a speech-to-text system offered by Amazon, was used to eavesdrop on prisoners’ phone calls.

    In a sales pitch, LEO’s CEO James Sexton told officials working for a jail in Cook County, Illinois, that one of its customers in Calhoun County, Alabama, uses the software to protect prisons from getting sued, according to an investigation by the Thomson Reuters Foundation.

    Continue reading
  • Battlefield 2042: Please don't be the death knell of the franchise, please don't be the death knell of the franchise

    Another terrible launch, but DICE is already working on improvements

    The RPG Greetings, traveller, and welcome back to The Register Plays Games, our monthly gaming column. Since the last edition on New World, we hit level cap and the "endgame". Around this time, item duping exploits became rife and every attempt Amazon Games made to fix it just broke something else. The post-level 60 "watermark" system for gear drops is also infuriating and tedious, but not something we were able to address in the column. So bear these things in mind if you were ever tempted. On that note, it's time to look at another newly released shit show – Battlefield 2042.

    I wanted to love Battlefield 2042, I really did. After the bum note of the first-person shooter (FPS) franchise's return to Second World War theatres with Battlefield V (2018), I stupidly assumed the next entry from EA-owned Swedish developer DICE would be a return to form. I was wrong.

    The multiplayer military FPS market is dominated by two forces: Activision's Call of Duty (COD) series and EA's Battlefield. Fans of each franchise are loyal to the point of zealotry with little crossover between player bases. Here's where I stand: COD jumped the shark with Modern Warfare 2 in 2009. It's flip-flopped from WW2 to present-day combat and back again, tried sci-fi, and even the Battle Royale trend with the free-to-play Call of Duty: Warzone (2020), which has been thoroughly ruined by hackers and developer inaction.

    Continue reading
  • American diplomats' iPhones reportedly compromised by NSO Group intrusion software

    Reuters claims nine State Department employees outside the US had their devices hacked

    The Apple iPhones of at least nine US State Department officials were compromised by an unidentified entity using NSO Group's Pegasus spyware, according to a report published Friday by Reuters.

    NSO Group in an email to The Register said it has blocked an unnamed customers' access to its system upon receiving an inquiry about the incident but has yet to confirm whether its software was involved.

    "Once the inquiry was received, and before any investigation under our compliance policy, we have decided to immediately terminate relevant customers’ access to the system, due to the severity of the allegations," an NSO spokesperson told The Register in an email. "To this point, we haven’t received any information nor the phone numbers, nor any indication that NSO’s tools were used in this case."

    Continue reading

Biting the hand that feeds IT © 1998–2021