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Humans are so skilled at pattern-seeking, and so taken with the notion of actively-managed destinies, that they regularly (and sometimes tragically) mistake routine coincidental events for fragments of some cosmic strategist's grand plan. A similar effect once caused Apple Computer to make its iPod shuffle sequences less random in order to seem more random. Mlodinow's core theme is that the modern echoes of Laplace's determinist view of the world, embodied in the notion of a personal destiny for each human being, are, on balance, harmful to clear and critical thinking. Mlodinow and other educators striving to explain and clarify the immense influence of chance events on our daily lives. But the author provides many examples showing that even the most "obvious" causal chains were far more randomly influenced than they appeared to be in the seductively misleading light of 20-20 hindsight.Although it may sound cynical and discouraging at first, the view promoted in this book is actually healthier and ultimately more optimistic than reliance on a mysterious, intelligently- guided "destiny" which needlessly causes us to agonize over the imagined motives of a nonexistent grand supervisor. Among the general public, a pervasive lack of appreciation for the importance of randomness often shows up in casual pronouncements such as "There are no coincidences." It is hard to imagine a less true claim.Mlodinow guides the reader through ten chapters forming an entertaining introduction to probability and statistics, with many interesting sidelights. Countless people could significantly sharpen their understanding of the world and its workings if only they would pay attention to Prof. Having given the reader a useful store of background knowledge in the first nine chapters, the author introduces the kernel of the book's conclusions in chapter 10, which carries the book's main title ("The Drunkard's Walk").
One such is an explanation of Benford's law, which has helped catch criminals trying to fake random number sequences in illegal lotteries. In fact, says the author, some of the characteristics of random series are so counterintuitive that people may imagine they detect a bias. Our pattern-prone minds are endlessly creative at linking events and experiences into a seemingly coherent version of what some invisible intelligence has in store for us, or has used to influence the fate of others. Just as Darwin found a certain grandeur in the immensely long trial-and-error saga of evolution, we can take comfort in the recognition that we all face the same spectrum of strictly impersonal odds in the daily lottery of life.
I bought this book for my husband for Christmas. He wasn't all that impressed with the book.he said he knew most of the information from his college and graduate school statistics courses (he's an engineer). For someone wanting to learn about statistics it's probably a good read, though.
Regression Towards the Mean means that on average, people perform at the average of their abilities. It is really easy to read, and it is chocked full of examples where very smart people made very bad decisions. It highlights very well that in general, people are terrible at recognizing randomness, and thus will always be controlled by it.Randomness is very unsettling to people, as such we have a tendency to give order and purpose to the world. and when they do present data, they almost never provide enough details to determine whether or not their results are "statistically significant." In other words, how do they know that their "supporting data" isn't just a great big coincidence.This book bucks that trend big time, and the results are very impressive.The author wrote this like a history book about the field of statistics, and how it evolved (slowly) over they years.
It doesn't sound monumental, but people forget it sometimes. One great example of this was discovered fairly recently, called "regression towards the mean." The author's example was as follows:A psychologist was visiting a group of Air Force instructors after World War 2 to help them design a new training program. But, if they do badly and I yell at them well, the next day they do MUCH better. I am typically disappointed with pop-science books written for the general public. it's why Roger Maris beat Babe Ruth's home run record, and then very few records after that. In fact, even if you get 6 positive mammograms in a row, you still have better than a 50/50 chance of being totally healthy. Do the math.
At which point, an instructor jumped up to yell at the psychologist for talking hogwash."When my students have a good day and I praise them, the next day they slack off and don't do as well. You need only be as talented as the average to have a great winning streak.My other favorite section was when the author covered false positives on medical tests. it's why some CEOs do amazingly well at one company, but then crash and burn when put in charge of another. He was telling the instructors that positive feedback was much more effective at getting people to learn than negative feedback. But, every time the author introduces a new concept in statistics, he also shares real-world situations where people made terrible mistakes because they didn't understand these basic principles. Most people -- most doctors even -- aren't good enough with statistics to understand when medical tests lead you astray. Towards the end of the book -- after a highly readable introduction to statistical theory -- he presents the following question: * assume breast cancer is present in 0.8% of the population * assume a mammogram says a healthy person has cancer 7% of the time (false positive) * if a mammogram says you have cancer, what are the odds you actually have cancer.Most people would assume that the answer is 93%, since there is a 7% false positive rate. and people will incorrectly assume that it's because of greater competency.
So don't tell me this 'positive feedback' garbage works, because it doesn't."Surprisingly, both the psychologist and the instructor were right. Likewise, if you do a task enough times, eventually you're going to have a 100-item winning streak that is entirely random luck. out of 1000 people getting a mammogram, 8 will have breast cancer (0.8% incident), and be told so. they usually don't present enough data for me to make up my own mind about their conclusions. But the correct answer is much different: if you test positive for cancer, there is only a 10% chance you actually have cancer.How is this possible.
When asked to a bunch of doctors, the average answer was actually around 70%. However, because of the false positive rate of 7%, another 70 people will be told that they have cancer, when in fact they don't. Medical tests for rare diseases are fraught with this kind of problem, and it's a shame doctors aren't better at telling their patients the true odds.Overall, I would recommend this book to everybody. but after that, any winning streaks are probably just dumb luck.It's the same reason why some mutual fund managers do better than others, but only for a few years. People frequently see patters where they just don't exist.
therefore, if you test positive for breast cancer, there's only about a 10% chance you actually need to worry. If you flip a coin enough times, eventually you'll get 100 heads in a row. Sure, you need to be competent enough to perform the task, and you need to do the task very frequently. That's 78 people who test positive for cancer, but only 8 actually have it. simply because they didn't understand how randomness rules our lives.
She quoted as an example the cool fact that Apple made the music selection of the Ipod Shuffle less random so that it would "appear more random" to the listener for not repeating back-to-back the same song or artist. Of course this calculator often miscalculates. As the wall is an impenetrable barrier regardless of the randomness of each stumble (to the right or to the left) the drunkard's future is inevitable:: he will end laying in the gutter. In that book the allegory included the drunkard walking down a sidewalk with a wall to the right side and a gutter to the left. So here are my pet peeves::1 - The book has a table of contents, an index and notes but it doesn't have a reference section or list of quoted books and papers sorted by author. The book is filled with other interesting situations from the sports world, gambling and a bold bet against an Aussie state lottery, trial by mathematics, education and grading, investing, medical care, and other aspects of our daily lives.The book also recounts in chronological order the major developments in probability and statistics with interesting background information on the mathematician responsible for each breakthrough.
At every step the theory is presented in a very simple though meaningful way by use of practical examples. What my journalist friend probably didn't realize is that I am a trained geo-statistician or someone who makes a living by applying probability distribution and statistical analysis to assessing mineral deposits and this gives me special tinted lenses through which I tend to see the world. A friend who is a journalist recommended me this book over some beers. - baseball. So it puts us back in the 16th century at best;4 - In The Blank Slate Steven Pinker explains how the human brain has a simple built in probability calculator. An additional chapter on Mlodinow's book addressing behavioural psychology, the physiology and evolution of this primitive built in probability calculator would be, in my opinion, a great addition.5 - I first read about the "Drunkard's Walk" on the book Full House: The Spread of Excellence from Plato to Darwin by Stephen Jay Gould. If you never had the chance to study statistics in college or if you did it many years ago and never really practised it here is an entertaining way to get a crash or refresher course.
There was no need for the corny humour;3 - The book explains how the lack of mathematical notation held back for centuries advances in math and science. This example shows how we often misinterpret randomness. With this allegory and a competent introduction to probability the late Stephen Jay Gould tries to prove that the apparent trend of evolution to climb a ladder of complexity with mankind atop is nothing more than a drunkard's walk contained on one side by the lower limit of complexity in living organisms. This has become standard in modern nonfiction books;2 - Randomness is a fascinating subject and the author has researched it well and filled the book with fascinating examples. The equal sign, according to the book, was invented in the year 1557 by the British mathematician Robert Recorde, but the book does not have a single equal sign or a single mathematical expression for that matter. I prefer Gould's allegory and in many respects I prefer Full House over Mlodinow's book but Full House is focused in evolutionary biology and - what else. If you, like myself, see things through jaundiced eyes then reach down to the bottom of your pocket and the bottom of your purse and pull out that pair of cheap sunglasses.Leonardo AlvesBelo Horizonte - Brazil - 2010
This is the science that modern day business, government, and medicine heavily depend on, indeed is part of our everyday life.From the book, originally from a real game show: say you are presented with three doors, behind one is a car to win, nothing behind others. Thumbs up. (Amazon knows, bet on that)This book introduces readers to random process, probability and statistics from a very familiar day-to-day point of view with no math or formula. This is the science that has significantly advanced most other physical and social sciences. If you think it does not matter whether you switch or stay, you think the same way as many (including myself initially), but are wrong.More amazing thought provoking examples about conditional probabilities, false positives and false negatives, measurement errors, etc. The story roughly follows the history of development of probability and statistics and is built with historical tales and modern day stories of how, like it or not, randomness is an integral part of our lives.
Without opening that door, the game show host helps you improve your decision by opening one of the other doors with no car behind it, and let's you make another choice: either stay with the originally selected door or switch to the other unopened door. What was the chance of that. You select one door. Many examples of fallacies of human thought illustrate how human brain is not wired to think in probabilities. We are talking about gross systematic mistakes made by humans, including doctors in diagnosis and treatment, judges in weighing evidence, by PhDs, Wall Street experts, etc.This is the science that requires gambler's intuition rather than a scientific mind. Should you switch.
But you get the point.
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