Monday, December 26, 2016

Black Swans Fly At Night

Few individuals are more annoying than those who are ‘smart after the event’. To put it more precisely, they are smart only after an event, but rarely prior to it. I am sure everyone can recall dozens of examples. Mainstream media outlets are bursting with them.

For instance, the UK’s recent pro-Brexit vote was hardly predicted before the summer referendum; but, ever since, hack journalists and self-appointed ‘experts’ have been falling over themselves to explain its inevitability. For me, post hoc wisdom verges on fraudulent. Anyone can do it. Of course, some did predict the outcome correctly and proceeded to broadcast their foreknowledge as loudly as possible, implying that ‘I was one of just a select few who, all along, could see it coming’. Even this is often disingenuous. If one makes enough predictions, however outlandish, some are statistically bound to be accurate. Does a stopped clock not tell the correct time twice every day?

The so-called ‘Black Swan Theory’ is a clever metaphor for a special type of surprise occurrence. It was first put forward by a Lebanese-American professor, Nassim Nicholas Taleb (Figure 101.1), in 1991. Taleb’s neat idea relates to a difficult-to-predict event which proves highly consequential and can be rationalized only with hindsight. Political analysts are some of the worst offenders. They explain so many events, with great authority and eloquence, as if everything were blatantly obvious from the beginning (when they never thought to say so). The 2008 financial earthquake is another excellent case in point. Before the crisis, hardly any analysts foresaw it; afterwards, almost all of them supposedly did.

Figure 101.1: Nassim Nicholas Taleb (1960-) is a former mathematical trader and Distinguished Professor of Risk Engineering at New York University’s Polytechnic Institute.

Copyright © 2016 Edge

The black swan reference originates from ancient folk wisdom: black swans (Figure 101.2) were believed not to exist because no one had ever seen one. Eventually, when such birds were identified, the presumption was instantly falsified. As the saying goes, absence of evidence does not equate to evidence of absence. (That said, please read Irving Copi’s Introduction to Logic if you feel inclined to disagree.)

Figure 101.2: A rare sighting of Cygnus atratus

Copyright © 2012 Stanford University

Taleb’s subject is a fascinating one to explore. Why, then, do black swans – the events, not the biological species – exist? I would say that nearly all individuals are hoodwinked by psychological bias, where they are more likely to accept new evidence if it concurs with their existing beliefs. Individual bias is then compounded by collective confirmation bias, because individuals tend to surround themselves with those that share similar views. Thus, even patently false or ridiculous beliefs can become entrenched.

It is said that we see only what we want to see. I would disagree: we see what we expect to see, as a result of psychological bias, whatever the extent of its veracity. If something did not exist yesterday, why be on the lookout for it today?

The night sky is full of black swans. A few will be sighted in 2017, and myriad know-alls will emerge from the woodwork and claim to have seen the birds invisible flight paths. I suspect, though, that the vast majority will continue to fly unseen. Some truly audacious ones might even repeatedly swoop and dive right in front of our faces  and still remain unnoticed. Food for thought, anyone (Figure 101.3)?

Figure 101.3: Do you see?

Copyright © 2016 Paul Spradbery

Copyright © 2016 Paul Spradbery

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