The Rules of Contagion

its ad provider. The provider then shows this information to a group of
automated traders acting on behalf of advertisers. After another 0.07
seconds, the traders will have bid for the right to show us an advert.
The ad provider selects the winning bid and sends the advert to our
browser, which slots the advert into the webpage as it loads on the
screen.[81]
People don’t always realise that websites work in this way. In
March 2013, the UK Labour party tweeted a link to a new press
release criticising then Education Secretary Michael Gove. One
Conservative MP responded by tweeting about the choice of advert
on Labour’s website. ‘I know Labour are short of cash but having an
invitation to “Date Arab girls” at top of your press release?’ he wrote.
Unfortunately for the MP, other users pointed out that the Labour
page featured targeted advertising: the offer on display was likely to
depend on a user’s specific online activity.[82]
Some of the most advanced tracking has cropped up in places we
might least expect it. To investigate the extent of online targeting,
journalism researcher Jonathan Albright spent early 2017 visiting
over a hundred extreme propaganda websites, the sort of places that
are full of conspiracy theories, pseudoscience, and far-right political
views. Most of the websites looked incredibly amateurish, the sort of
thing a beginner would put together. But digging behind the scenes,
Albright found that they concealed extremely sophisticated tracking
tools. The websites were collecting detailed data on personal identity,
browsing behaviour, even mouse movements. That allowed them to
follow susceptible users, feeding them even more extreme content. It
wasn’t what users could see that made these websites so influential;
it was the data harvesting that they couldn’t.[83]
How much is our online data actually worth? Researchers have
estimated that users who opt-out of sharing their browsing data are
worth about 60 per cent less to advertisers on Facebook. Based on
Facebook’s revenue in 2019, this implies that data on the behaviour
of the average American user is worth at least $48 per year.
Meanwhile, Google reportedly paid Apple $12bn to be the default
iPhone search engine for 2019. With an estimated one billion iPhones