If Big Tech has our data, why are targeted ads so terrible?

 Click HERE

Personalised advertising is the dirty fuel that powers some of the world's biggest tech giants. 

Data is supposed to be the new oil - a resource so valuable it warrants multibillion-dollar market valuations.

Just as mail services cannot open letters and use information inside to make money from advertisers, so campaigners say browsing histories and other online data should be treated as private.

Internet giants are so effective at wielding the data they collect that they can predict and influence the behaviour of millions of people - a scare story promoted since the 2016 victories of Brexit and Mr Donald Trump.

"There is not enough distinction between correlation and causation," he says. "Look at eBay."

the people clicking on search ads were the ones already planning to buy something on the site. eBay was wasting millions of dollars.

Relate to 2017 'A' level AQ on swarm mentality and sharing of data....