The book, "The Drunkard's Walk: How randomness rules our lives," looks at randomness and really randomness plays a greater role in what happens with humans than people, in general, think. I found the book to be exceptional. Although I have always suspected what the book claims, the book backs up its conclusions with mathematics. Plus, it does it in a fun way, making for a very enjoyable book, also. Although not specifically a financial or investing book, the book really is helpful in understanding such stuff. Some points which I noted are....
1. Human intuition is ill suited to uncertainty since in the 1930's researchers noted that people couldn't make sequences of random numbers nor recognize a random sequence.
2. Sometimes in life things happen which can't be foreseen.
3. The amygdala in the brain is active when making a decision, hence decisions are emotional.
4. Rewards work, but punishment doesn't. The opposite is just regression to the mean.
5. Examples which are more likely due to randomness - Roger Maris/1961, success of certain movies and studio heads.
6. Research has shown that people will assign greater probabilities to outcomes which are described in greater detail, the "availability bias."
7. Arithmetic didn't really exist until the 16th century, hence probability not understood before then.
8. DNA in courts - lab error = 1/11, DNA = 1/1B, so chance of error more like 1/10.
9. The Law of Sample Space - Gerolano Cardano - the Book of Games of Chance - 16th century.
10. The Probability of Points - 2 entities competing.
11. Pascal's Triangle - if need to know # of ways in which you can choose some # of objects from a collection that has a > or = #. Pascal's wager -odds about consequences of a pious life, 1/2 if G-d exists, ie. if pious. Confusing, but discussed.
12. Sweepstakes - cost of mail cheaper than chance of winning. Lottery, odds of winning same as one person dying driving to place which sells lottery tickets, but not advertised that way. Dice and roulette wheel are not perfectly balanced, so some uncertainty, not predictable.
13. The book mentions calculus and how it is composed of 1) a sequence, a succession of elements,b) a series which is the sum of the sequence of elements, and 3) a limit where the sequence is heading. But, in Zeno's paradox, the paradox is resolved because of constant motion, no stops. That's how Bernouli attacked the the relationship between probability and observation - toss a coin 10x maybe 7 heads, toss a zillion times expect 50% heads. Bernouli's Golden Theorem - large enough sample to ensure confidence within a certainty. Too small of a sample = the law of small numbers. For instance 1/3 chance that 5 of a CEO's performance will reflect his ability, so better to analyze his abilities rather than just look at results.
14. Bayes's Theorem is discussed where conditional probabilities. Prosecutor's fallacy/ mistake of inversion - just because A happens then B doesn't mean if B happens A will happen. Examples are SIDS deaths and OJ trial.
15. Understanding and quantifying random error led to a new field - mathematical statistics.
16. Wine tasting influenced by all kinds of things, price, context. Statistical measurements include standard deviation, standard deviation squared = variance. Also the Error Law known as a normal distribution or bell curve - in certain cases can expect certain proportionality of results. But, social physics not all normal, like Pareto principle - 80/20 rule or regression to the mean concept. Brownian motion shows Drunkard's Walk, randomness.
17. Book mentions V2 rocket attacks in WWII and cancer clusters, more due to randomness than predictable patterns. The human need to feel in some control interferes with the accuracy in perceiving natural events.
18. Lorenz's Butterfly effect - just small changes can lead to massive differences in results. Plus, unlike laws of physics, human affairs are too complex to predict. Asymmetry makes things impossible to predict, yet look predictable on retrospect, like the stock market. Also, people failing or in poverty may be more random than predictable.
In summary, a terrific book - will likely change the way a reader looks at things, or if a reader does think that way the book will show the mathematics behind it, in a very readable form. 5 out of 5 stars.
