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 What happens to the Turkey on the 1001st day? July 24, 2008
0 out of 2 found this review helpful
I can't comment on the science behind this book. I will say that - at least from this layman's perspective - Taleb offers magnitudes of insight on the ideas of unpredictability and randomness, and does a bang-up job of upsetting the status quo.
The book is centered on the concept of a Black Swan - an event that lies outside the narrow periphery of our knowledge, has an extreme impact or causes a major upset (whether it be cultural, financial, political, et al.), and is characterized by a rampant slew of retrospectives - all the media, the so-called "experts", and the authorities suddenly have the details on why it happened.
For instance, we are told by historians of the outbreak of WW2: "tensions were mounting" throughout Europe, and that there were "escalating crises" abound, but according to bond prices (which offer a good understanding of history, says Taleb), there was no sign of this to speak of! "One would suppose that people living through the beginning of WW2 had an inkling that something momentous was taking place. Not at all."
The idea of retrospective distortion and over-interpretation fascinates me. How people attempt to fit messy empirical reality into neatly organized interpretations! The problem with our predictions, and our retrospectives, is that they are often framed from a naive perspective that we live in a place called Mediocristan, a place where randomness is mild, or Type 01, when we really live in a place called Extremistan - where reality is characterized by wild, unpredictable events that completely upset the averages of the bell curve.
...We come out the other side mistrusting the arrogance of almost all predictions! What does bird poop have to do with one of the most fundamental physical theories? Do we think that our wars are "under-control", or do we consider the unpredictability of conflict - that a small conflict might someday spiral unpredictably out of control and result in the decimation of the entire human race!?! How has the Nobel Prize been exploited to sell methods of market-interpretation that are completely unscientific, yet universally accepted and completely institutionalized? We are treated to an interesting investigation of this arrogance which dominates so many fields of study and indeed, we find that it is an arrogance deeply embedded in our minds!
Despite the seemingly bleak picture, The Black Swan is great fun to read and offers tips ("be as hyper-conservative and as hyper-aggressive as you can!") on how to cope and perhaps even thrive in this chaotic, simmering soup we call Civilization.
If you are like me, you will enjoy reading about things like the narrative fallacy, confirmation bias, the ludic fallacy, the problem of induction, et al. My only criticism of book is it's repetition, but honestly - I hardly noticed.
 A world few people live in. July 23, 2008
2 out of 2 found this review helpful
Wealth Odyssey: The Essential Road Map For Your Financial Journey Where Is It You Are Really Trying To Go With Money?
This work says more about the world of hedge funds and speculation than it does about the world most people live in. "Everything is possible, yet only one thing happens" is a quote from "Chances are ... Adventures in Probability" by Michael and Ellen Kaplan, a much easier to read work without laborious philosophy wrapped around otherwise good information. Yes, things happen. "Pop! Why Bubbles are Great for the Economy" by Daniel Gross, explains that unexpected things do indeed happen, which is often a good thing.
Nothing can be predetermined or forecast. There is more to life than worrying about black swans, which may never happen. The illusion is that even if one did know, how would knowing it make life any different after it happened? Yes, for those not living in Pompeii it mattered. Nevertheless, a super volcano for example (or any other cataclysmic event - geophysical or financial), a true black swan, would change life, as we know it, globally - unstated, but a result of his definition. To approach investing just in case a black swan comes along has more of an impact on the present results, for those holding such beliefs, since the odds of the black swan are small. Indeed, any traumatic black swan would affect everyone's results and all would be in the same boat. Otherwise, it wouldn't be a true black swan, simply a localized, unforeseen, occurrence for those holding such views.
 Nebulous with the odd bright spot July 23, 2008
1 out of 1 found this review helpful
Any book that attempts to explain a nebulous concept such as this is hard to write but the presentation of this book is very cumbersome.
The only parts I liked was Chapters 1-3 which has some interesting observations about rare events and how most humans are hardwired to miss the rare event and Chapters 15-17 are quite good: I think most readers will relish the discussion on bell curves and standard deviations.
Chapters 5-15 are completely unreadable in which the author "discusses" the works and hypothesis of unknown french-philosophers with weak connections to the book's subject.
This book doesn't offer a clue on predicting rare events and offers a lot of hindsight advice. Most readers will find Taleb's suggestions totally inapplicable to their work. The biggest shortcoming of this book is its treatment (lack of) conditional probability and its dismissal of intelligent action as merely "random" events.
 The Abnormality of Normal Distributions July 20, 2008
1 out of 2 found this review helpful
Nassim Taleb's Black Swan makes for a fascinating read, despite (or perhaps because of) his heavily self-important style of writing. Taleb strikes at the core of the human tendency to prophesize, or more humbly, forecast all kinds of things. The reason why almost everyone gets it so wrong all the time, even while making predictions about seemingly mundane things (e.g., a project plan for building construction), is that they ignore the impact of "black swans", seemingly rare events. Taleb's contention is that while specific black swans are difficult to predict, the occurrence of some black swan or the other is very widespread in all walks of human life. In mathematical terms, Taleb contends that a lot of real life phenomena that are modeled using Normal or Gaussian distributions, are in fact governed by a Power Law distribution.
Taleb introduces the notions of Mediocristan and Extremistan, the former including all areas of measurement where the outlier event does not make much of a difference to the average (e.g., the average weight of any population sample will not be skewed by the fattest or the thinnest person), and the latter includes all areas where the outlier (or the black swan) typically dominates the sample (e.g., Bill Gates' wealth would dominate any sample of the wealth of1000s of people of which he was one). Taleb points out that Extremistan is more widespread and commonplace than we'd imagine, and that we commonly end up making the mistake of applying Mediocristan tendencies of averaging, linear extrapolation and Gaussian distributions to situations that belong to Extremistan.
Taleb argues that humans have a natural tendency to forecast, even though most previous forecasts have been proven wrong. In addition to ignoring the black swan, some of the reasons for incorrect forecasting include:
oConfusing cause and effect, or attaching unreasonable probabilities to events, due to "narrative fallacy": We have a tendency to believe statements of the form "U.S. Treasuries rise; Hussein Capture may not curb terrorism", which treats one event as a cause for the other. Similarly, people are likely to consider the scenario "A massive flood somewhere in America in which more than a thousand people die" as being less likely than the more narrative scenario "An earthquake in California, causing massive flooding, in which more than a thousand people die", even though the first scenario is more inclusive than the second.
oIgnoring "silent evidence" and drawing incorrect cause-effect relationships: Taleb quotes Cicero's story about Diagoras who, when shown the portraits of worshippers who prayed and then survived a shipwreck (the implicit suggestion being that the praying helped prevent their drowning), remarked "where are the portraits of those who prayed, and then drowned?". We often infer cause and effect relationships from incomplete data, because the only data we see has "the winner's bias". By ignoring silent evidence, we give an undue importance to the role of certain actions towards causing an outcome, instead of ascribing the outcome to luck or randomness.
oConfusing the uncertainty that averages out with the uncertainty in real life: We often confuse the unpredictable uncertainties we deal with (e.g., how long will the Iraq War last) to the more well-behaved uncertainties we find in the rolling of dice and casino games.
Even if we opened our eyes to these mistakes, Taleb argues that we can not predict most real life phenomena. Modeling real life events using the Gaussian distribution is incorrect, because the assumptions behind the Gaussian (that all changes happen in a series of small steps, and that the odds are balanced at each step) do not hold in real life.
So what's one to do in the face of these difficulties in forecasting? Taleb offers his prescriptions: First, do not try to predict a specific black swan, and instead just expect some black swan to happen; and second, take actions that expose yourself aggressively to black swans (i.e., expose yourself to wild upsides and downsides) but at the same time protect your downside using some form of insurance. For example if you are investor, invest 15% of your portfolio in wildly unpredictable assets, and invest the remaining in safe insured assets.
Overall, I found Taleb's book a great read for anyone who uses data in decision making. It exposes a lot of mistakes I have seen myself and people around me make. I would strongly recommend this book to anyone, and I feel that reading The Black Swan will help any reader improve their understanding (or at least expose our lack of understanding) of the workings of the world around us.
Pompous and annoying July 17, 2008
1 out of 2 found this review helpful
As others have observed, there are a couple of good ideas in this book. The style, however, makes it practically unreadable. I actually listened to the audiobook; one of the editorial reviews comments that the reader salvaged the work somewhat by softening the sarcastic and annoying tone; I did not find that to be the case. It's hard to blame the narrator, as he seems to have captured more-or-less the author's intent.
The "couple of good ideas" are fairly straightforward. One, don't assume that you know the form of the probability distribution of any given social or economic phenomenon. That's good advice. It's often easy to find a function and a set of parameters that appear to fit a given historical data set; but just because the function appears to fit historically doesn't mean it's going to be predictive. Two, if the form of the distribution is unknown and unknowable, then computed measures of "risk" are not reliable, as risk is in fact incalculable. So, a good investing strategy is to avoid assets whose valuation depends on risk estimates, and seek out certain other assets. Following that strategy would have kept you out of a lot of the asset classes that have melted down recently.
The most frustrating problem with the way the book is written is its lack of self-consistency. For example, there is a long discussion of "silent evidence": just because you don't observe something doesn't mean it's not there. Then, over and over again, Taleb tries to assert that no one in business, or the social sciences, or this or that domain understands a certain issue correctly. Even if we assume for a moment that Taleb's understanding of the point in question is correct, and that he is therefore qualified to pass judgement on who is a Right-Thinking Individual, the fact that he has not encountered any Right-Thinking Individuals does not mean they don't exist. He may not have met them; or he may have met them and not been listening when they spoke; or he may have met them and presented his ideas in such a contemptuous way they chose not to engage in conversation, concluding there would be no value to themselves in it.
Then there is the rant against the bell curve that occupies the last chapters of the book. Kind of silly to get angry at a mathematical function. It's like criticizing a hammer for not being a screwdriver. In a few places the author does draw the distinction between appropriate uses of the bell curve and inappropriate uses, which is of course the (perfectly reasonable) point he is trying to make. Most of this section, however, is written in a much more sloppy and imprecise way, so that any sentence or paragraph by itself comes across as criticizing the hammer. To make sense of it one has to keep saying to oneself "well what he really means is that there are certain people who misuse this tool, and they shouldn't."
Similarly, the assault on academic economics and the Nobel Prize. Not many people would argue that idealized models are predictive of reality. That's not the same as saying they are without value; it just means one has to know what to use them for. The author does find value in behavioral economics, but somehow when attacking academia seems to forget that a) behavioral economics is all the rage today in academic circles, and b) the Nobel committee, who Taleb considers so clueless, awarded Kahneman the economics prize for inventing it. [Another self-consistency issue here: after a very lengthy discursion on the value of empiricism and the fallacy of oversimplified models, Taleb confidently repeats numerous experimental-psychology and behavioral-economics results as "the way we behave," where by "we" he means all of humanity, excluding perhaps himself the Enlightened One. In fact, most of these results are based on very small samples, so while they are indeed interesting, the authors generally go to great lengths to explain that what they have observed COULD have a certain meaning or cause, but that the data are not conclusive, as other causes could have led to the same observations.]
Great books are like great friends. Even when they challenge your ideas, you want to enage with them because it's such a pleasure. This is not such a book. The ideas, while interesting, are not as controversial as the author claims, and they aren't worth the pain of struggling through the writing.
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