Jesse Frederick:

For more than a century, advertising was an art, not a science. Hard data didn’t exist. An advertising guru of the Don Draper
type proclaimed: “What you call love was invented by guys like me to sell nylons”

– and advertisers could only hope it was true. You put your commercials on the air, you put your brand in the paper, and you started praying. Would anyone see the ad? Would anyone act on it? Nobody knew.

In the early 1990s, the internet sounded the death knell for that era of advertising. Today, we no longer live in the age of Mad Men, but of Math Men.

Looking for customers, clicks, conversions? Google and Facebook know where to find them. With unprecedented precision, these data giants will get the right message delivered to the right people at the right time. Unassuming internet users are lured into online shops, undecided voters are informed about the evils of US presidential candidate Elizabeth Warren, and cars zip by on the screens of potential buyers – a test drive is only a click away.

But is any of it real? What do we really know about the effectiveness of digital advertising? Are advertising platforms any good at manipulating us?

You’d be forgiven for thinking the answer to that last question is: yes, extremely good. After all, the market is huge. The amount of money spent on internet ads goes up each year. In 2018, more than $273bn dollars was spent on digital ads globally, according to research firm eMarketer. Most of those ads were purchased from two companies: Google ($116bn in 2018) and Facebook ($54.5bn in 2018).