• Tous les prix incluent la TVA.
Il ne reste plus que 4 exemplaire(s) en stock (d'autres exemplaires sont en cours d'acheminement).
Expédié et vendu par Amazon. Emballage cadeau disponible.
The Wisdom of Crowds a été ajouté à votre Panier
+ EUR 2,99 (livraison)
D'occasion: Bon | Détails
Vendu par -betterworldbooks-
État: D'occasion: Bon
Commentaire: Expedier des Etats-Unis. Distribution privu en 2-3 semaines. Nous proposons la communication par e-mail en francais. Le dos et les coins peuvent montrer des signes d'usure. Les pages peuvent inclure des notes et quelques signes de feutre. Sous garantie de remboursement complet. Plus de plus d'un million clients satisfaits! Votre alphabétisation dans le monde achat avantages!
Vous l'avez déjà ?
Repliez vers l'arrière Repliez vers l'avant
Ecoutez Lecture en cours... Interrompu   Vous écoutez un extrait de l'édition audio Audible
En savoir plus
Voir les 3 images

The Wisdom of Crowds (Anglais) Broché – 16 août 2005

4.0 étoiles sur 5 3 commentaires client

Voir les formats et éditions Masquer les autres formats et éditions
Prix Amazon
Neuf à partir de Occasion à partir de
Format Kindle
"Veuillez réessayer"
"Veuillez réessayer"
EUR 28,47 EUR 1,21
Broché, 16 août 2005
EUR 9,10
EUR 8,91 EUR 0,01
"Veuillez réessayer"
EUR 236,89 EUR 41,99
Cassette, Livre audio
"Veuillez réessayer"
EUR 47,08
Note: Cet article est éligible à la livraison en points de collecte. Détails
Récupérer votre colis où vous voulez quand vous voulez.
  • Choisissez parmi 17 000 points de collecte en France
  • Les membres du programme Amazon Premium bénéficient de livraison gratuites illimitées
Comment commander vers un point de collecte ?
  1. Trouvez votre point de collecte et ajoutez-le à votre carnet d’adresses
  2. Sélectionnez cette adresse lors de votre commande
Plus d’informations
click to open popover

Offres spéciales et liens associés

  • Outlet Anciennes collections, fin de séries, articles commandés en trop grande quantité, … découvrez notre sélection de produits à petits prix Profitez-en !

  • Rentrée scolaire : trouvez tous vos livres, cartables, cahiers, chaussures, et bien plus encore... dans notre boutique dédiée

Produits fréquemment achetés ensemble

  • The Wisdom of Crowds
  • +
  • How To Win Friends And Influence People.
Prix total: EUR 16,59
Acheter les articles sélectionnés ensemble

Descriptions du produit


The Wisdom of Crowds


If, years hence, people remember anything about the TV game show Who Wants to Be a Millionaire?, they will probably remember the contestants' panicked phone calls to friends and relatives. Or they may have a faint memory of that short-lived moment when Regis Philbin became a fashion icon for his willingness to wear a dark blue tie with a dark blue shirt. What people probably won't remember is that every week Who Wants to Be a Millionaire? pitted group intelligence against individual intelligence, and that every week, group intelligence won.

Who Wants to Be a Millionaire? was a simple show in terms of structure: a contestant was asked multiple-choice questions, which got successively more difficult, and if she answered fifteen questions in a row correctly, she walked away with $1 million. The show's gimmick was that if a contestant got stumped by a question, she could pursue three avenues of assistance. First, she could have two of the four multiple-choice answers removed (so she'd have at least a fifty-fifty shot at the right response). Second, she could place a call to a friend or relative, a person whom, before the show, she had singled out as one of the smartest people she knew, and ask him or her for the answer. And third, she could poll the studio audience, which would immediately cast its votes by computer. Everything we think we know about intelligence suggests that the smart individual would offer the most help. And, in fact, the "experts" did okay, offering the right answer--under pressure--almost 65 percent of the time. But they paled in comparison to the audiences. Those random crowds of people with nothing better to do on a weekday afternoon than sit in a TV studio picked the right answer 91 percent of the time.

Now, the results of Who Wants to Be a Millionaire? would never stand up to scientific scrutiny. We don't know how smart the experts were, so we don't know how impressive outperforming them was. And since the experts and the audiences didn't always answer the same questions, it's possible, though not likely, that the audiences were asked easier questions. Even so, it's hard to resist the thought that the success of the Millionaire audience was a modern example of the same phenomenon that Francis Galton caught a glimpse of a century ago.

As it happens, the possibilities of group intelligence, at least when it came to judging questions of fact, were demonstrated by a host of experiments conducted by American sociologists and psychologists between 1920 and the mid-1950s, the heyday of research into group dynamics. Although in general, as we'll see, the bigger the crowd the better, the groups in most of these early

experiments--which for some reason remained relatively unknown outside of academia--were relatively small. Yet they nonetheless performed very well. The Columbia sociologist Hazel Knight kicked things off with a series of studies in the early 1920s, the first of which had the virtue of simplicity. In that study Knight asked the students in her class to estimate the room's temperature, and then took a simple average of the estimates. The group guessed 72.4 degrees, while the actual temperature was 72 degrees. This was not, to be sure, the most auspicious beginning, since classroom temperatures are so stable that it's hard to imagine a class's estimate being too far off base. But in the years that followed, far more convincing evidence emerged, as students and soldiers across America were subjected to a barrage of puzzles, intelligence tests, and word games. The sociologist Kate H. Gordon asked two hundred students to rank items by weight, and found that the group's "estimate" was 94 percent accurate, which was better than all but five of the individual guesses. In another experiment students were asked to look at ten piles of buckshot--each a slightly different size than the rest--that had been glued to a piece of white cardboard, and rank them by size. This time, the group's guess was 94.5 percent accurate. A classic demonstration of group intelligence is the jelly-beans-in-the-jar experiment, in which invariably the group's estimate is superior to the vast majority of the individual guesses. When finance professor Jack Treynor ran the experiment in his class with a jar that held 850 beans, the group estimate was 871. Only one of the fifty-six people in the class made a better guess.

There are two lessons to draw from these experiments. First, in most of them the members of the group were not talking to each other or working on a problem together. They were making individual guesses, which were aggregated and then averaged. This is exactly what Galton did, and it is likely to produce excellent results. (In a later chapter, we'll see how having members interact changes things, sometimes for the better, sometimes for the worse.) Second, the group's guess will not be better than that of every single person in the group each time. In many (perhaps most) cases, there will be a few people who do better than the group. This is, in some sense, a good thing, since especially in situations where there is an incentive for doing well (like, say, the stock market) it gives people reason to keep participating. But there is no evidence in these studies that certain people consistently outperform the group. In other words, if you run ten different jelly-bean-counting experiments, it's likely that each time one or two students will outperform the group. But they will not be the same students each time. Over the ten experiments, the group's performance will almost certainly be the best possible. The simplest way to get reliably good answers is just to ask the group each time.

A similarly blunt approach also seems to work when wrestling with other kinds of problems. The theoretical physicist Norman L. Johnson has demonstrated this using computer simulations of individual "agents" making their way through a maze. Johnson, who does his work at the Los Alamos National Laboratory, was interested in understanding how groups might be able to solve problems that individuals on their own found difficult. So he built a maze--one that could be navigated via many different paths, some shorter, and some longer--and sent a group of agents into the maze one by one. The first time through, they just wandered around, the way you would if you were looking for a particular cafe* in a city where you'd never been before. Whenever they came to a turning point--what Johnson called a "node"--they would randomly choose to go right or left. Therefore some people found their way, by chance, to the exit quickly, others more slowly. Then Johnson sent the agents back into the maze, but this time he allowed them to use the information they'd learned on their first trip, as if they'd dropped bread crumbs behind them the first time around. Johnson wanted to know how well his agents would use their new information. Predictably enough, they used it well, and were much smarter the second time through. The average agent took 34.3 steps to find the exit the first time, and just 12.8 steps to find it the second.

The key to the experiment, though, was this: Johnson took the results of all the trips through the maze and used them to calculate what he called the group's "collective solution." He figured out what a majority of the group did at each node of the maze, and then plotted a path through the maze based on the majority's decisions. (If more people turned left than right at a given node, that was the direction he assumed the group took. Tie votes were broken randomly.) The group's path was just nine steps long, which was not only shorter than the path of the average individual (12.8 steps), but as short as the path that even the smartest individual had been able to come up with. It was also as good an answer as you could find. There was no way to get through the maze in fewer than nine steps, so the group had discovered the optimal solution. The obvious question that follows, though, is: The judgment of crowds may be good in laboratory settings and classrooms, but what happens in the real world?


At 11:38 am on January 28, 1986, the space shuttle Challenger lifted off from its launch pad at Cape Canaveral. Seventy-four seconds later, it was ten miles high and rising. Then it blew up. The launch was televised, so news of the accident spread quickly. Eight minutes after the explosion, the first story hit the Dow Jones News Wire.

The stock market did not pause to mourn. Within minutes, investors started dumping the stocks of the four major contractors who had participated in the Challenger launch: Rockwell International, which built the shuttle and its main engines; Lockheed, which managed ground support; Martin Marietta, which manufactured the ship's external fuel tank; and Morton Thiokol, which built the solid-fuel booster rocket. Twenty-one minutes after the explosion, Lockheed's stock was down 5 percent, Martin Marietta's was down 3 percent, and Rockwell was down 6 percent.

Morton Thiokol's stock was hit hardest of all. As the finance professors Michael T. Maloney and J. Harold Mulherin report in their fascinating study of the market's reaction to the Challenger disaster, so many investors were trying to sell Thiokol stock and so few people were interested in buying it that a trading halt was called almost immediately. When the stock started trading again, almost an hour after the explosion, it was down 6 percent. By the end of the day, its decline had almost doubled, so that at market close, Thiokol's stock was down nearly 12 percent. By contrast, the stocks of the three other firms started to creep back up, and by the end of the day their value had fallen only around 3 percent.

What this means is that the stock market had, almost immediately, labeled Morton Thiokol as the company that was responsible for the Challenger disaster. The stock market is, at least in theory, a machine for calculating the present value of all the "free cash flow" a company will earn in the future. (Free cash flow is the money that's left over after a company has paid all its bills and its taxes, has accounted for depreciation, and has invested in the business. It's the money you'd get to take home and put in the bank if you were the sole owner of the company.) The steep decline in Thiokol's stock price--especially compared with the slight declines in the stock prices of its competitors--was an unmistakable sign that investors believed that Thiokol was responsible, and that the consequences for its bottom line would be severe.

As Maloney and Mulherin point out, though, on the day of the disaster there were no public comments singling out Thiokol as the guilty party. While the New York Times article on the disaster that appeared the next morning did mention two rumors that had been making the rounds, neither of the rumors implicated Thiokol, and the Times declared, "There are no clues to the cause of the accident."

Regardless, the market was right. Six months after the explosion, the Presidential Commission on the Challenger revealed that the O-ring seals on the booster rockets made by Thiokol--seals that were supposed to prevent hot exhaust gases from escaping--became less resilient in cold weather, creating gaps that allowed the gases to leak out. (The physicist Richard Feynman famously demonstrated this at a congressional hearing by dropping an O-ring in a glass of ice water. When he pulled it out, the drop in temperature had made it brittle.) In the case of the Challenger, the hot gases had escaped and burned into the main fuel tank, causing the cataclysmic explosion. Thiokol was held liable for the accident. The other companies were exonerated.

In other words, within a half hour of the shuttle blowing up, the stock market knew what company was responsible. To be sure, this was a single event, and it's possible that the market's singling out of Thiokol was just luck. Or perhaps the company's business seemed especially susceptible to a downturn in the space program. Possibly the trading halt had sent a signal to investors to be wary. These all are important cautions, but there is still something eerie about what the market did. That's especially true because in this case the stock market was working as a pure weighing machine, undistorted by the factors--media speculation, momentum trading, and Wall Street hype--that make it a peculiarly erratic mechanism for aggregating the collective wisdom of investors. That day, it was just buyers and sellers trying to figure out what happened and getting it right.

How did they get it right? That's the question that Maloney and Mulherin found so vexing. First, they looked at the records of insider trades to see if Thiokol executives, who might have known that their company was responsible, had dumped stock on January 28. They hadn't. Nor had executives at Thiokol's competitors, who might have heard about the O-rings and sold Thiokol's stock short. There was no evidence that anyone had dumped Thiokol stock while buying the stocks of the other three contractors (which would have been the logical trade for someone with inside information). Savvy insiders alone did not cause that first-day drop in Thiokol's price. It was all those investors--most of them relatively uninformed--who simply refused to buy the stock.

But why did they not want Thiokol's stock? Maloney and Mulherin were finally unable to come up with a convincing answer to that question. In the end, they assumed that insider information was responsible for the fall in Thiokol's price, but they could not explain how. Tellingly, they quoted the Cornell economist Maureen O'Hara, who has said, "While markets appear to work in practice, we are not sure how they work in theory."

Maybe. But it depends on what you mean by "theory." If you strip the story down to its basics, after all, what happened that January day was this: a large group of individuals (the actual and potential shareholders of Thiokol's stock, and the stocks of its competitors) was asked a question--"How much less are these four companies worth now that the Challenger has exploded?"--that had an objectively correct answer. Those are conditions under which a crowd's average estimate--which is, dollar weighted, what a stock price is--is likely to be accurate. Perhaps someone did, in fact, have inside knowledge of what had happened to the O-rings. But even if no one did, it's plausible that once you aggregated all the bits of information about the explosion that all the traders in the market had in their heads that day, it added up to something close to the truth. As was true of those who helped John Craven find the Scorpion, even if none of the traders was sure that Thiokol was responsible, collectively they were certain it was.

Revue de presse

“As entertaining and thought-provoking as The Tipping Point by Malcolm Gladwell.... The Wisdom of Crowds ranges far and wide.” –The Boston Globe“A fun, intriguing read–and a concept with enormous potential for CEOs and politicos alike.” –Newsweek“This book is not just revolutionary but essential reading for everyone.”–Christian Science Monitor“Provocative....Musters ample proof that the payoff from heeding collective intelligence is greater than many of us imagine.” –BusinessWeek“There’s no danger of dumbing down for the masses who read this singular book.” –Entertainment Weekly“Clearly and persuasively written.” –Newsday“Convincingly argues that under the right circumstances, it’s the crowd that’s wiser than even society’s smartest individuals. New Yorker business columnist Surowiecki enlivens his argument with dozens of illuminating anecdotes and case studies from business, social psychology, sports and everyday life.” –Entertainment Weekly“The author has a knack for translating the most algebraic of research papers into bright expository prose.” –The New York Times Book Review"Dazzling . . . one of those books that will turn your world upside down. It's an adventure story, a manifesto, and the most brilliant book on business, society, and everyday life that I've read in years." –Malcolm Gladwell, author of The Tipping Point “Surowiecki’s clear writing and well-chosen examples render complicated mathematical and sociological theories easy to grasp. . . . [His] accounts of how the wisdom of crowds has formed the world we live in will thrill trivia mavens–and may make a better investor (or football coach) out of anyone who takes its conclusions to heart.” –Time Out New York"This book should be in every thinking businessperson's library. Without exception." –Po Bronson, author of What Should I Do With My Life?
“Drawing from biology, behavioral economics, and computer science, Surowiecki offers answers to such timeless–and often rhetorical–questions as “Why does the line you’re standing in always seem to move the slowest?” and “Why is there so much garbage on TV?” The result is a highly original set of conclusions about how our world works.” –Seed Magazine“As readers of Surowiecki’s writings in The New Yorker will know, he has a rare gift for combining rigorous thought with entertaining example. [The Wisdom of Crowds] is packed with amusing ideas that leave the reader feeling better-educated.” –Financial Times (London)“The book is deeply researched and well-written, and the result is a fascinating read.” –Deseret Morning News"Jim Surowiecki has done the near impossible. He's taken what in other hands would be a dense and difficult subject and given us a book that is engaging, surprising, and utterly persuasive. The Wisdom of Crowds will change the way you think about markets, economics, and a large swatch of everyday life." –Joe Nocera, editorial director of Fortune magazine and author of A Piece of the Action “Makes a compelling case.” –The Gazette (Montreal)“Deftly compressing a small library’s worth of research into a single slim and readable volume, the Financial Page columnist at The New Yorker makes his bid to capture the zeitgeist as his colleague Malcolm Gladwell did with The Tipping Point. . . . The author has produced something surprising and new: a sociological tract as gripping as a good novel.” –Best Life“Surowiecki is a patient and vivid writer with a knack for telling examples.” –Denver Post "Most crowds of readers would agree that Jim Surowiecki is one of the most interesting journalists working today. Now he has written a book that will exceed even their expectations. Anyone open to re-thinking their most basic assumptions–people who enjoyed The Tipping Point, say–will love this book." –Michael Lewis, author of Moneyball
“Surowiecki’s is a big-idea book.” –Salon.com"It has become increasingly recognized that the average opinions of groups is frequently more accurate than most individuals in the group. The author has written a most interesting survey of the many studies in this area and discussed the limits as well as the achievements of self-organization." –Kenneth Arrow, winner of the Nobel Prize in Economics and Professor of Economics (Emeritus), Stanford University“Clever and surprising.... The originality and sheer number of demonstrations of the impressive power of collective thinking provided here are fascinating, and oddly comforting.” –Bookforum“An illuminating book.” –Detroit Free Press

Aucun appareil Kindle n'est requis. Téléchargez l'une des applis Kindle gratuites et commencez à lire les livres Kindle sur votre smartphone, tablette ou ordinateur.

  • Apple
  • Android
  • Windows Phone
  • Android

Pour obtenir l'appli gratuite, saisissez votre numéro de téléphone mobile.

Détails sur le produit

Commentaires en ligne

4.0 étoiles sur 5
5 étoiles
4 étoiles
3 étoiles
2 étoiles
1 étoile
Voir les 3 commentaires client
Partagez votre opinion avec les autres clients

Meilleurs commentaires des clients

Format: Broché
Ce livre est plus journalistique que scientifique mais reste une lecture passionnante. Il explique quelques mécanismes pyschologiques qui permettent à un groupe ou à une foule de se comporter (parfois) de manière intelligente, coordonnée, conforme à l'intérêt du groupe, et de dépasser les capacités limitées et les intérêts égoïstes de ses membres.

Résumé du livre sur :

Remarque sur ce commentaire 9 personnes ont trouvé cela utile. Avez-vous trouvé ce commentaire utile ? Oui Non Commentaire en cours d'envoi...
Merci pour votre commentaire.
Désolé, nous n'avons pas réussi à enregistrer votre vote. Veuillez réessayer
Signaler un abus
Par Romur TOP 500 COMMENTATEURS le 9 novembre 2008
Format: Broché
James Surowiecki propose une approche et une analyse intéressantes de l'intelligence collective (dont l'archétype est Wikipedia) et des meilleures façons de la susciter et de l'exploiter : diversité, indépendance, décentralisation, mécanisme neutre de consolidation... Facile à lire, illustré d'exemples concrets, il fournit des idées, outils et méthodes pratiques pour la vie professionnelle.

Il présente toutefois le défaut de ne faire aucune analyse critique sur les limites de sa thèse, et mène un impressionnant et parfois pénible plaidoyer pour la doctrine américaine de libre concurrence, son économie de marché et sa démocratie. Un peu de recul et moins d'américano-centrisme aurait été souhaitable.
Remarque sur ce commentaire 9 personnes ont trouvé cela utile. Avez-vous trouvé ce commentaire utile ? Oui Non Commentaire en cours d'envoi...
Merci pour votre commentaire.
Désolé, nous n'avons pas réussi à enregistrer votre vote. Veuillez réessayer
Signaler un abus
Format: Relié
"The wisdom of crowds" est une causerie, pas très organisée, sur le fascinant sujet de la collaboration, coopération et action concordante au sein des groupes humaines .
L'auteur illustre par des nombreux exemples -tirés des domaines les plus inattendus- son thèse principale: une foule est plus sage que le plus intelligent et le plus informé des personnes qui la composent, précisément puisqu'elle part d'une diversité des opinions.
L'auteur prend ainsi la contrepartie de l'image dominante -dans la sociologie comme pour le bon sens- de la foule vue comme une collection d'individus dirigée par des émotions primaires et portée à prendre des décisions plus hâtives, radicales et destructrices que celles que la moyenne des personnes qui s'y trouvent auraient pris.
L(auteur tempère ses propos sur les effets bénéfiques du regroupement des individus, en détaillant - de manière plus ou moins convaincante ( car partant d'une série d'études de psychologie sociale expérimentale, choisis pour appuyer les convictions de l'auteur) - les conditions nécessaires pour que la coopération se mette en place et puisse exercer ses effets bénéfiques.
Remarque sur ce commentaire Avez-vous trouvé ce commentaire utile ? Oui Non Commentaire en cours d'envoi...
Merci pour votre commentaire.
Désolé, nous n'avons pas réussi à enregistrer votre vote. Veuillez réessayer
Signaler un abus

Commentaires client les plus utiles sur Amazon.com (beta)

Amazon.com: 4.0 étoiles sur 5 296 commentaires
3 internautes sur 3 ont trouvé ce commentaire utile 
5.0 étoiles sur 5 Important and Paradoxical 4 janvier 2009
Par Steven Farron - Publié sur Amazon.com
Format: Broché Achat vérifié
Surowiecki's The Wisdom of Crowds documents and analyzes an extremely important phenomenon. When people guess at a question to which nearly no one knows the answer but most people can make a sensible guess (e.g., what proportion of the world's airports are in the USA; how many marbles can fit into a box that is a meter on each side) the average of a large group is nearly always more accurate than the guess of any member of that group. Moreover, the more people involved, the more accurate the average is.
This phenomenon was first discovered by Francis Galton, Charles Darwin's first cousin. Throughout his life, Galton was obsessed with measurement and categorization. His study of fingerprints led to their use by the police to identify criminals. His study of twins revealed that biological heredity determines intelligence and temperament. He also worked out the coefficient of correlation, which is a basis of modern statistics. In 1906, when Galton was eighty-five and still as inquisitive as ever, he visited a country fair. One of the events was a contest to try to guess what the weight of an ox, which was on display, would be after it had been killed and dressed. In order to enter the contest, a person had to pay sixpence and write his guess, along with his name and address, on a piece of paper. After the contest was over, Galton borrowed the papers with the guesses. There were 787 papers in total. To his amazement, the average guess was only one pound less that the actual weight (1,198 pounds). That was closer than any individual guess. Yet, some of the participants in the contest were butchers and cattle raisers, who would be expected to do much better than the average.
This phenomenon also applies to predictions of future events. That is why it is nearly impossible to make money consistently by betting on sporting events - because the odds are determined by the average of all bets, which is extremely accurate. The most striking illustration of this phenomenon is the otherwise inexplicable fact that, with very few exceptions, professional stock investors (managers of mutual funds, pension funds, etc.) do worse than the stock market indexes. Professional investors are highly intelligent people, who devote all their time to analyzing stocks and stock market trends; they have specially developed soft-ware and teams of assistants. But their analyses are not as accurate as the average analysis of all investors.
However, for the wisdom of crowds to work, two conditions must be met (pages 10-11, 36-7). One is that the opinions of the individuals involved must be formed and expressed independently of the others. When decisions are made by groups meeting together, the group is often swayed by a consensus that seems to have formed or by one or two of its member who seem to have more expertise, or who express their opinions forcefully. Also, the individuals involved must have some knowledge of what is involved. For example, the average prediction of Indonesian peasants as to which team will win the National Football League championship would be worthless.
In line with the second condition, the wisdom of crowds does not apply to areas of technical expertise. The average guess of a crowd as to the weight of an ox when it has been slaughtered and dressed is more accurate than the estimate of any butcher in the crowd. But the butchers in the crowd are more adept than any non-butchers at carving the ox, storing its meat, and preparing it for sale.
Surowiecki offers a general explanation (pages 10-11) for why the crowds are wiser than any of their individual members and specific reasons (pages 34, 44-50) for why professional stock investors do worse than the stock indexes. I found the latter explanations more convincing than the former.
Surowiecki also discusses (pages 236, 245-6) the obvious objection that the average prices of stocks, houses, and commodities often rise and fall sharply, without regard to the value of the assets involved. Such price swings do not occur with ordinary goods and services, such as televisions or haircuts; nor does a rise in price of ordinary goods and services induce more people to buy them. Average predictions of the results of sporting events or of elections are also immune from irrational price bubbles. In these cases, the accuracy of the predictions is decided unequivocally at a specific time in the near future. That keeps the crowd tethered to reality. But when the prices of stocks, houses, and commodities rise, that means that they can be resold at a higher price; and there is no point at which the bet is definitely over and the bettors have undeniably been proved right or wrong.
9 internautes sur 9 ont trouvé ce commentaire utile 
4.0 étoiles sur 5 Smoothly written, valuable points, somewhat one-sided 25 mars 2005
Par Max More - Publié sur Amazon.com
Format: Relié Achat vérifié
Crowds have a bad rap. Our opinion of collective decision making and behavior has been darkened by first-hand observation of events such as the stock market bubble and crash, and by classic works such as Extraordinary Popular Delusions and the Madness of Crowds, and The Crowd: A Study of the Popular Mind. That is unfortunate, argues James Surowiecki because, under the right circumstances, groups "are remarkably intelligent, and are often smarter than the smartest people in them."

If nothing else, The Wisdom of Crowds should entertain you. It may not do much more than this if you are already well read in economics, complexity theory, decision analysis, organizational theory, social psychology, prospect theory and other fields. Few readers will have delved into all the relevant areas to any great extent, so most can expect to learn something new, interesting, and quite possibly useful. Surowiecki's wide-ranging gathering of sources to support his argument is a virtue, yet it's also something of a problem. The difficulty of knowing much about all the areas on which he draws makes it easy for him to pick and choose studies and arguments selectively. While many of his points are well made, the way he supports his case sometimes seems one-sided.

In evaluating and supporting the idea of the wisdom of crowds, Surowiecki looks at how collective intelligence can be applied to three kinds of problems: Cognition problems (which have definitive solutions), coordination problems, and cooperation problems (which require self-interested agents to work together). The first half of the book sets out the theory, thoroughly and entertainingly illustrated by examples. These include the smarts of the audience on game shows, how to design an excellent search engine, why short selling is a good thing, and how a group finds a lost submarine. The second half of the book applies the ideas to show various ways in which people organize toward common goals in cases such as traffic, science, juries, committees, business organizations, markets, and democracies.

Among the main points that may be useful to executives, Surowiecki emphasizes that for the crowd to be wise, it must be characterized by diversity of opinion, independence of members from one another, and a specific kind of decentralization, and there needs to be a good method for aggregating opinions. He stresses that the best collective decisions result from disagreement and contest, not consensus or compromise.

While corporations often rely on experts, the book does well at challenging our confidence in expertise as compared to the average of the crowd. In the course of a discussion of the role of independence, we learn that to improve your organization's decision making you should ensure that decisions are made simultaneously rather than one after the other. Finally, I have to second Surowiecki's puzzlement at the apparent lack of interest by companies in using markets (such as decision markets) for corporate strategy and market research.
6 internautes sur 6 ont trouvé ce commentaire utile 
4.0 étoiles sur 5 Worth a quick read 5 décembre 2005
Par Kenneth Posner - Publié sur Amazon.com
Format: Relié Achat vérifié
Surowiecki's book focuses on the strengths and weaknesses of collective decision-making. The text covers a large number of issues rather superficially, and it will not satisfy those looking to dive into and master the underlying economic theories. But it makes an important point and can be read quickly.

His thesis is that groups of people can aggregate information to produce surprisingly accurate decisions. The book starts by recounting a famous experiment, in which a 19th century Scottish scientist studied the results of a typical contest where county fair-goers guessed the weight of an ox. He found that, while many guesses were wide of the mark, the mean of the guesses was spot on -- and closer to the ox's actual weight than any individual guess. Apparently this phenomenon holds true for other such contests (how many jellybeans in a jar or how much a pumpkin weighs) -- and this ought to make one stop and think about the power of aggregating information from groups of ordinary people.

Surowiecki relates the power of group thinking to other situations, ranging from the efficacy of market prices to the eery accuracy of the Iowa Electronic Markets (which forecast election results among other things).

He contrasts these examples with the dangers of "group think," the consensual and wrongheaded approach to decision-making that plagues governments and corporations, the frequently poor quality of "expert" forecasts, and the volatility of security prices (he explains the theory of "information cascades" in a clear and easy-to-follow manner).

The moral of the story: "Diversity and independence are important because the best collective decisions are the product of disagreeemant and contest, not consensus or compromise." It strikes me that this bit of wisdom could be usefully applied in government, business, investing, and many other walks of life; hence the value of the book, even if you skim it quickly.
7 internautes sur 7 ont trouvé ce commentaire utile 
5.0 étoiles sur 5 A good book to read and reread 16 février 2005
Par Henry Cate III - Publié sur Amazon.com
Format: Relié Achat vérifié
In "The Wisdom of Crowds" James Surowiecki explores how often a group of people can make better decisions than the "expert" and under what situations might a group make poor choices.

One of the basic points of the book is that in making a decision people have two components, information and error. Often by aggregating the decisions of many individuals the errors will cancel out and you are left with a very good decision. Another point is that for complex problems there is no "expert" who completely and thoroughly understands the problem, and can thus give the "right" answer. Most big problems are solved by making our best guesses and then seeing if our decisions were right or good enough. A group of people, because together they have more information, can make better choices.

James Surowiecki uses a variety of interesting examples to discuss how much better decisions a group can make. His first example is how Francis Galton found that an average group of people at a county faire in England back one hundred years ago were able to guess the weight of an ox within a pound, much closer than any of the "experts" were able to get. It was fascinating to learn that within hours of the Challenger Space Shuttle explosion the stock market picked which company was responsible, by a big drop in the stock price, long before there was any clear understanding of what had happened. And within a couple weeks the international health community was able work together to understand SARS, without any guiding hand or one organization in charge.

The author also explores under what conditions a group of people might make a poor decision. He found that a group of experts, who all tend to have a similar viewpoint on a particular topic, may make a worse decision than a group with a few "less smart" people who will see a problem from different view points. Another situation that happens is where there is a vague problem for which people don't see a clear answer so if someone will go public with his answer, then other people will go along with the first answer, rather than making their best guess. He calls this information cascade. It is better that everyone be encouraged to make their best guess, and then work through a process of resolving or aggregating the decisions.

The chapter on how to pick good solutions for issues raised by new technology was fascinating. The author compared the process of how the free market finds good solutions to how a beehive looks for food. One example was the early development of the automobile. In both cases scouts go out looking for solutions (honey or car designs) and bring them back to be evaluated by the group. The market reviewed hundreds of designs for cars and gave feedback on which designs were better. The basic design quickly developed. It is key to have a system which generates lots of alternatives and allows losers to be abandoned quickly. It is important to have both diversity of solutions and diversity of perspectives to generate better results.

Some books are interesting and educational, but after reading them there is little need to go back and reread them. You can learn the basic lessons in one reading. "The Wisdom of Crowds" is one of those which needs to be reread every so often because there are so many interesting ideas explained and thoughts explored. It is well written and is worth the time to read and worth thinking about after reading.
1 internautes sur 1 ont trouvé ce commentaire utile 
5.0 étoiles sur 5 great stuff! 9 novembre 2008
Par ponto - Publié sur Amazon.com
Format: Broché Achat vérifié
I read this for a MBA class. Out of the stack of books assigned, so far, this is the only one I liked. It is relevant to today's curious questions of how to get crowds engaged, how crowds behave, and why we even care.

I'm trying to teach people to work collaboratively together at work. They "think" they already are doing this but the author gives me new ideas on how to further their participation in team work. I find that in corporate america, people contribute mostly in their assigned role. "I am a business analyst so I don't give my 2 cents when solutioning". Yikes it drives me crazy that they put their single hats on then multi-task when we start talking about something that isn't their specialty.

Anyway, I underlined something on every other page which is a sign that I found this useful and something I will want to learn to apply.

Did I mention how good a writer this guy is?
Ces commentaires ont-ils été utiles ? Dites-le-nous


Souhaitez-vous compléter ou améliorer les informations sur ce produit ? Ou faire modifier les images?