The Black Swan

I’ve just finished reading The Black Swan by Nassim Taleb. I found it one of the most interesting books I ever read. If you had some statistics course and are interested in on how the human mind works or a fan of the books of Malcolm Gladwell I can recommend you reading this book.

Nassim Taleb basically tells us that we as humans are very bad in predicting because many things have mainly been determined by highly improbable events.  E.g. all kinds of inventions like the Internet, the car or things like wars, stock market crashes etc. As Nassim Taleb says it: “History doens’t crawl  it jumps”

Furthermore the world is so complex that the human mind simply cannot understand what’s going on.  Still we always try to understand it and come with explanations, and get convinced that we see the patterns and that we can predict because that is what we have been trained for. A funny example of that is the following experiment. Give people the sequence 2, 4, 6 and tell them that this sequence is generated according to a rule and ask people to tell you what the rule is. To get some more information they can ask you if a certain three number sequence is generated also according to that rule. Most people will think that the rule is adding two so they probably will ask you if 4, 6, 8 is generated by your rule. And it is, but the rule is not add two. The rule is very simple that the 3 numbers have to be ascending but people will fall for the pattern of add two. This is because people think in terms of confirmation of rules instead of contradictions. You will see with this game that many people won’t try quickly sequences contradict the rule they have in their mind. While one contradiction says more about a rule than a million confirmations.

That’s also how the book got it’s title “The Black Swan”. Until Australia was discovered people thought there were only white swans, because every time they saw a swan it was white. Discovery of Australia and boom a black swan. Using the fact that you saw another white swan to confirm you’re theory that there are only white swans is the same as saying “Hey a red Mini Cooper another proof there are only white swans”. This might sound funny but it’s actually mathematically true. (Think about it or read the book)

Another thing that struck is Nassim Taleb’s explanation why we keep on listening to experts doing predictions if we just can’t predict. E.g we take advice on which stocks to buy from so called experts. How do they remain experts while market crashes have proven over and over again that they are wrong quite often? Furthermore when they are wrong it can have disastrous effects because the Black Swans they fail to predict have usually huge effects. They remain experts with their models because they have the excuse that certain things could never be in their models because they simply couldn’t predict it. E.g.  how could they have known about 9/11. If they would have known they of course would have predicted that the stock markets would have tanked after that.

Funny thing is that while Nassim Taleb tries to prove that we should not trust any prediction he actually predicts in 2007 that Fannie Mae will get into financial problems (“they are sitting on a barrel of dynamite”) because of the risks they are taking. However the “scientific” staff of Fannie Mae at that time says that this is unlikely to happen.

Anyway these are just a few of the stories and concepts of the book.