To the average person, the billboard on the bus stop on London's Oxford Street was a standard coffee-brand ad. Every few seconds, the digital poster would change. Sometimes, it would feature a wide range of drab grays and blocks of text. Other times, it was a minimalistic image with a short saying. What was unique about this particular poster, which ran in two locations at the end of July 2015, wasn't the fact that people were looking at it. Rather, it was looking at them — and learning. Using facial tracking technology and genetics-based algorithms, the poster took the aspects that people looked at the longest and then incorporated that into the next design evolution. "We were surprised how quickly it learned," said Sam Ellis, business director of innovation at M&C Saatchi. "It got to a state of where it felt like it was in the right place a bit faster than we thought." In less than 72 hours, the M&C Saatchi advertisement was creating posters in line with the current best practices in the advertising industry, which had been developed over decades of human trial and error like realizing three to five word slogans work best. "We thought [our employees] would be nervous about it: Is this going to kill off creative?" Ellis said. "What they started to realize is that it could be really, really useful based on its insight." M&C Saatchi's Ellis believes eventually ad agencies will be smaller, because AI will be able to accomplish tasks with a high degree of accuracy — for much less money than now — and will make outsourcing tasks a lot more effective. As our machines become more sophisticated and more details about our lives are recorded as data points, AI is getting to the point where it knows a tremendous amount about humans. It can tell what a person is feeling. It knows the difference between a truth and a lie. It can go through millions of permutations in a second, coming up with more variations than a human could think of. It knows your daily routine, like when you're most likely going to want a cold beer on a hot summer day.

"The AI economy is going to be the most disruptive thing we've ever seen," said Winston Binch, chief digital officer of agency Deutsch North America. "It's tough because the pace of technological change is so fast, we don't know what to do with it." This leads to the question: How far are we from the day where AI is going to be better at creating advertising than the creators themselves? "We all have to be a little unnerved by this," Binch said. A $10 BILLION INDUSTRY AND GROWING

Some forecasts have pegged the AI industry at $10 billion globally today, with spending growing in the double digits annually, according to Deloitte LLP. A United Nations report suggested as much as two-thirds of all jobs in developing countries could be affected by "significant automation." "There is no question that there is strong and rapidly growing investment in this area, spanning hardware, software, cloud and services," said David Schatsky, managing director of Deloitte LLP. "But the impact of cognitive will likely be much greater than the sum of the investments in the technology. A growing number of companies are already benefiting from cognitive technologies that are embedded in the products and services they buy and use." Businesses like Netflix use AI to power its movie and TV show recommendations, according to a Deloitte report titled "Cognitive technologies: The real opportunities for business." Meanwhile, the Associated Press uses language-generation AI to write corporate earnings stories. The concept of machines being capable of logical reasoning has been around since the 14th century, but it wasn't until 1956 after a conference at Dartmouth College that people began earnestly researching the subject. By the late 1990s, AI was being used for data mining and other logical deduction tasks. But, it wasn't until March of 2016 that AI was able to do the previously impossible: Beat a human at a game that required highly advanced reasoning and deductive skills. In other words, Google's AlphaGo was able to "think." Go is a Chinese game that involves using stones to take over more "territory" on the playing square. The number of possible moves in the game is said to be more than the number of atoms in the observable universe. The human opponent had some advantages over AlphaGo: The computer couldn't shift its playing strategy once the match started, or think on the fly and be creative with its moves. That's because, for now at least, the best AI only has about the equivalent of a couple hundred brain neurons, said Stephen Pratt, CEO of enterprise AI company Noodle.ai, a partnership with TPG Growth. For comparison, the human brain has 100 billion. "For the foreseeable future, you absolutely need humans as the genesis of ideas and the creative director, and to understand the final product is good and it is effective," Pratt said. In the movie "Minority Report," "precogs" were able to determine if someone was likely to commit a crime, Pratt said. In advertising, while there aren't mutated humans capable of determining your future, AI can "absolutely" determine if a person is more likely to purchase a product and what kinds of things might compel them to want to buy it. It's not quite the same thing, but the technology is getting there.

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