Friday, 15 July 2016

Musings & Amusings

Unclouded vision

Forecasting is a talent. Luckily it can be learned.

Human beings cannot resist trying to scry the future. If soothsaying is not the oldest profession, it is certainly one of them.

The Chinese had the I-Ching; the Romans peered at the entrails of sacrificed animals. These days, anyone wanting to know what the future holds can consult everything from telephone psychics to intelligence agencies, bookies, futures markets and media pundits. Their record is far from perfect. But it is difficult to say just how imperfect: for all the importance people attach to forecasting, hardly anyone bothers to keep score.

Superforecasters are clever, on average, but by no means geniuses. More important than sheer intelligence was mental attitude. Borrowing from Sir Isaiah Berlin, a Latvian-born British philosopher, Mr Tetlock divides people into two categories: hedgehogs, whose understanding of the world depends on one or two big ideas, and foxes, who think the world is too complicated to boil down into a single slogan. Superforecasters are drawn exclusively from the ranks of the foxes.

Humility in the face of a complex world makes superforecasters subtle thinkers. They tend to be comfortable with numbers and statistical concepts such as “regression to the mean” (which essentially says that most of the time things are pretty normal, so any large deviation is likely to be followed by a shift back towards normality).

But superforecasters do have a healthy appetite for information, a willingness to revisit their predictions in light of new data, and the ability to synthesise material from sources with very different outlooks on the world. They think in fine gradations.

Most important is what Mr Tetlock calls a “growth mindset”: a mix of determination, self-reflection and willingness to learn from one’s mistakes. The best forecasters were less interested in whether they were right or wrong than in why they were right or wrong. They were always looking for ways to improve their performance. In other words, prediction is not only possible, it is teachable.

Talk of growth mindsets, statistical fluency and a complicated world may sound dry and technical. It is not. Mr Tetlock’s thesis is that politics and human affairs are not inscrutable mysteries. Instead, they are a bit like weather forecasting, where short-term predictions are possible and reasonably accurate.

Source: The Economist