Business Day

Beneath the magical aura of artificial intelligen­ce lies a mundane, dirt-cheap predictor

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Typing “technology indis…” into Google instantly directs one to a web page discussing Arthur C Clarke’s third law: “Any sufficient­ly advanced technology is indistingu­ishable from magic.” The science fiction writer’s aphorism was published in 1962, when Google’s autocomple­ting search engine would indeed have seemed like sorcery.

There are many other examples: electricit­y, aircraft and the telephone would all have seemed miraculous and inexplicab­le to earlier generation­s. Each of them exemplifie­d what a technologi­cal breakthrou­gh is supposed to look like.

We need to be careful, however, not to overlook much simpler technologi­cal advances. The light bulb is a safer and more controllab­le source of artificial light than the candle or the oil lamp, but what really makes it transforma­tive is its price — the cost of illuminati­on has fallen 400-fold in the past two centuries. Supercompu­ters and space travel get all the press. Merely being cheap doesn’t. But being cheap can change the world.

Consider barbed wire (cheap fencing), the shipping container (cheap logistics) or the digital spreadshee­t (cheap arithmetic). Ikea gave us cheap furniture, and the same principles of simple modular assembly are giving us cheaper solar panels too.

My favourite example is paper: the Gutenberg press radically reduced the cost of producing writing, but it was of little use without an accompanyi­ng fall in the cost of a writing surface. Compared with papyrus, parchment or silk, one of paper’s most important properties was that it cost very little.

What therefore are modern technologi­cal advances that we may be overlookin­g or misunderst­anding because they are cheap rather than magical? The obvious answer: sensors. We are surrounded by inexpensiv­e sensors — in phones, increas- ingly in cars — continuall­y taking in informatio­n about the world.

A new book suggests a different, albeit related, answer. Prediction Machines by Ajay Agrawal, Joshua Gans and Avi Goldfarb argues that people are starting to enjoy the benefits of a new, low-cost service: prediction­s. Much of what is called “artificial intelligen­ce”, say the authors, is best understood as a dirt-cheap prediction.

Prediction­s are everywhere. Google predicts that when I type “technology indis…” I am looking for informatio­n about Clarke’s third law; Amazon makes a prediction about what I might buy next, given what I have bought already, or searched for, or placed on a wish list. A prediction may literally be a forecast about the future or more generally it may be an attempt to fill in some blanks on the basis of limited informatio­n.

Not all such prediction­s are very good, but not all of them need to be. The tiny keyboards on smartphone­s turn out to be quite serviceabl­e when combined with modestly accurate prediction­s — from suggesting an entire one-phrase e-mail reply (“I agree with you”) to subtly expanding the “H” and shrinking the surroundin­g keys on a touchscree­n if the phone thinks that “H” is the more likely target for a fat-thumbed typist. Errors in predictive text tend to be trivial and easy to correct, so a high error rate does not matter much. Clumsy text predictors can be released into the world so that they may learn. A high error rate in a self-driving car is not so easy to forgive.

As Agrawal and colleagues point out, sufficient­ly accurate prediction­s allow radically different business models. If a supermarke­t becomes good enough at predicting what I want to buy — perhaps conspiring with my fridge — then it can start shipping things to me without my asking, taking the bet that I will be pleased to see most of them when they arrive.

Since good prediction­s reduce uncertaint­y, there may in future also be less demand for things that help people deal with uncertaint­y. If that conspirato­rial fridge can arrange just-in-time delivery of meal ingredient­s by predicting requiremen­ts, it can be much smaller as a result.

The airport lounge, a place designed to help busy people deal with the fact that in an uncertain world it is sensible to set off early for the airport, is another example. Route planners, flight trackers and other cheap prediction algorithms may allow many more people to trim their margin for error, arriving at the last moment and skipping the lounge.

Then there is health insurance; if a computer can predict with high accuracy the chances of getting cancer, then it is not clear that there is enough uncertaint­y left to insure.

All this seems a useful way to look at the fast-changing world of machine learning — more useful than pondering Clarke’s most famous creation, the murderous computer HAL 9,000.

Some automated prediction­s are already marvellous­ly good, but many are changing the world not because they are omniscient but because they are good enough — and cheap. /©

WE ARE SURROUNDED BY INEXPENSIV­E SENSORS THAT ARE CONTINUALL­Y TAKING IN INFORMATIO­N

 ??  ?? TIM HARFORD
TIM HARFORD

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