Showing posts with label The Impact of the Highly Improbable. Show all posts
Showing posts with label The Impact of the Highly Improbable. Show all posts

Friday, June 24

Nassim Nicholas Taleb's The Black Swan. The Impact of the Highly Improbable


Nassim Nicholas Taleb's book has drawn a lot of attention since its publishing, especially due to the bold, revolutionary ideas it promotes. It goes from general, psychological and philosophical considerations to a rather technical thesis, challenging the statistical bell-curve's usefulness.
Taleb’s arguments follow two main directions: that there is much more randomness than people generally admit, and that dealing with it is troublesome because of the way people think. According to him, people should free themselves from the chains represented by statistics and probabilities, by what they think they know, and should give the impossible and luck, a chance.
There are numerous examples of success stories that start with a mere accident, of people who thrive out of pure luck (common sight in Extremistan), and also numerous stories of people who struggle to be in control of everything and never exceed their condition (the people of Mediocristan).
The world should give black swans, and the highly improbable, a chance, should focus on knowing "how to" rather than "what" moves the world. What would that bring about? Probably a wave of uncontrollable consequences, but that is not necessarily a bad thing, is it?  

Summary

The black swan referred to in the title is the one found in Australia, defying all previous observations according to which all swans were white. It is used to prove that induction can never bring certainty, as one exception is enough to invalidate the rule.
For the author, a black swan is an outlier, an exception, an improbability with extreme impact for which, after it happens, people create doubtful explanations (p. xviii). Relevant examples would be the “Lebanese paradise” destruction after 1975, the crash of the stock market in 1987, the USSR breakup, the 9/11 terrorist attack, and the internet's development. Some black swans have positive outcomes, but others do not.
Taleb believes the world we live in is one full of black swans with extreme consequences. People, no matter their background, do not usually accept the existence of realities like Extremistan or Mediocristan (p. 36), as the author calls them.
In the former, rewards are huge and have nothing to do with time, skill and effort, but a lot to do with luck and inequality rules. In the latter, a dull, predictable reality, jobs are rewarded based on the time, skills and effort invested, and extremes are rare, allowing a certain measure of equality.
The problem is that social sciences refuse to accept that Extremistan exists and outliers are important for society. Scientists and experts in all fields overestimate their knowledge and overlook the importance of what they do not know.
They give people the illusion that they understand, by selectively collecting and corroborating evidence or dead thinkers' thoughts (p. xxvii), while the real problem is how they think. People love stories, the “narrative fallacy” - believing in a less random world than the world really is, the “ludic fallacy” – believing that games approximate life, whereas they do not (p. 127).
Once they adopt a theory, people have a hard time giving it up when confronted with new evidence. They overrate facts relying on general knowledge, have a too narrow focus and depend too much on self-proclaimed experts.
Taleb considers that real experts have knowhow, and grain inspectors, chess masters, test pilots and physicists are the best examples. Those who possess know-what, like judges, stockbrokers, intelligence analysts, financial forecasters or political scientists are not real experts. He appreciates that military planners are the most knowledgeable, as they take into account the “unknown” (p. 127).
He offers many examples to show that people do not like to leave anything to chance. He sarcastically quotes financial press headlines interpreting unforeseen market shifts after they had happened. When forecasts turn out right, expertise is used as an explanation, but, when they are wrong, the experts are not to be blamed, or they have "nearly" nailed it.
Taleb turns to research to prove that, in economics and politics, not even the greatest experts, with their sophisticated analysis tools, can offer more accurate predictions than undergraduates using simple methods.
He states that many discoveries are made accidentally, by people looking for completely different things, and he gives the example of penicillin, laser or Viagra, with the latter designed to regulate blood pressure. He adds that technology adventurers strive due to the fact that common people worry about consequences (p.170).
The author declares himself against Platonicity, against people's tendency to mistake maps for territories, to focus on "forms" rather than on the reality. He proposes skeptic idols like Hume, Hayek, Popper and others. He agrees with Popper’s idea that the best way to verify a theory is to consider it false, and condemns the tendency of using the lack of evidence against a theory as an argument to prove its validity.

Evaluation

For Taleb, luck prevails over talent and hard word. People should accept it and move on. Talented people should focus on working in their field of interest, but remain alert to unexpected discoveries. It is alright to plan small matters, but bigger ones should leave room for trial and error.
When planning, one should focus not on probability, but on the gravity of the potential consequences, no matter how improbable. When investing, 85% of one's money should go into something risk-free, like Treasury bills, and only the remaining 15% should be scattered as venture capital.
Life should be seen as a derivatives series. By cutting negative exposure, people actually limit their vulnerability to the unknown (p. 329). The author advises them to consider as many opinions as possible, to go to as many parties as possible.
The Black Swan abounds in practical, easy to follow, justified ideas. Although some of them seem difficult to accept at first sight, they are so well explained and exemplified that adhering to them becomes easy. Indeed, there are many success stories in which luck plays a greater part than one would like to admit.
The author believes that evolution was survival of the luckiest, rather than survival of the fittest. And he is right to point out to people's risk calculation weaknesses – after 9/11, many gave up air travel considering highways safer, but the number of accidents actually rose. Philosophical research is cited to show that facts can be coherently interpreted using opposite explanations.
Taleb invites his readers to be skeptical, so why not begin with his own book. Although supported by convincing, well researched arguments, his exposition itself shows some weaknesses, beginning with the very black swan.
The discovery of the creature he named his book after, although contradicting all previous sightings, had no dramatic consequences, or, at least, the author failed to discuss them, and no one attempted to justify it. Another debatable issue would be the use of fictional characters to sustain his point.
The author can only understand they are fictional by reading the footnotes, and this is not one would expect or want to find in a book on the perception and understanding of reality. The use of narrative in the first part of the book, mostly anecdotes, to fight narrative is not too helpful either, even though Taleb argues that a story is needed for displacing another one (p. 28).
A closer look at the facts leaves some question marks as well. For example, while he claims that experts are mostly wrong, or not better than undergraduates at forecasting, he neglects the fact that political scientists’ generally succeed to predict the following events quite well and offer their reader the odds, so that the latter can decide by themselves what to expect and take for granted.
Even the 9/11 example can be challenged, since several terrorists were imprisoned in America for previously attempting to blow up World Trade Center, and there were several clues that something was being planned.
The American Statistician published review articles in which four statisticians show that Taleb was “statistically reckless”, ignoring those who study extremes (Lund, 189). He disregarded Hume’s anti-induction principles by considering his biased and limited statisticians' sample enough to allow him to assess that all statisticians are Mediocristan dwellers (Westfall and Hilbe, 193).
Of course, the truth and practicality of some of Taleb's ideas cannot be denied. Actually, it is impossible not to notice the similarity between public administration and Mediocristan, as a world in which people conform themselves to policy positions imposed by the politicians they elected, action and moderate speech is expected from public service members, and people are not supposed to get rich during their career. But even public administration has its share of thinking practitioners, it is a practical world in which people regard new theories with suspicion and hold success stories in high esteem.

Conclusion

While the book's intended audience ranges from academics and people with an already solid educational background to people activating in public sector innovation and administration, as indicated by the numerous notes (18 pages) and bibliography entries (27) from literature, philosophy, social sciences and finances, the accessible language makes it an interesting reading for anyone.
A detailed review of Taleb's work would require analysis of all of the facts and ideas presented, but one thing can be concluded based on the above observations: reading it can provide immense value to the reader, as long as it is regarded with the very skepticism the author recommends. Nothing should be taken for granted, and this book makes no exception.
References
Lund, Robert. 'Revenge Of The White Swan'. The American Statistician 61.3 (2007): 189-192. Web.
Taleb, Nassim Nicholas. 'Black Swans And The Domains Of Statistics'. The American Statistician 61.3 (2007): 198-200. Web.
Taleb, Nassim Nicholas. The Black Swan. New York: Random House, 2007. Print.


Westfall, Peter H, and Joseph M Hilbe. 'The Black Swan'. The American Statistician 61.3 (2007): 193-194. Web.