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Predictably Irrational: The Hidden Forces That Shape Our Decisions
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Predictably Irrational: The Hidden Forces That Shape Our Decisions

4.12  ·  Rating details ·  116,062 ratings  ·  6,128 reviews
Why do our headaches persist after taking a one-cent aspirin but disappear when we take a 50-cent aspirin?

Why does recalling the Ten Commandments reduce our tendency to lie, even when we couldn't possibly be caught?

Why do we splurge on a lavish meal but cut coupons to save twenty-five cents on a can of soup?

Why do we go back for second helpings at the unlimited buffet, eve
Hardcover, 247 pages
Published February 19th 2008 by HarperCollins Canada
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Serdar Yalçın There are some additions that the writer mentioned at the book. I bought the book for my kindle for 2 USD. I think the difference worth it. However th…moreThere are some additions that the writer mentioned at the book. I bought the book for my kindle for 2 USD. I think the difference worth it. However the book was on sale at the time, and I don't think it would worth paying 10 USD instead for the Revised and Expanded version.(less)

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Petra going to Mexico to hospital again, so hiatus
May 31, 2015 rated it liked it
Recommended to Petra going to Mexico to hospital again, so hiatus by: riku sayuj
“I asked them why when they persecute men, for religion or colour it was seen by the world as oppression and when they persecute women, it was dismissed as tradition.” Emer Martin

This book is generally brilliant if you ignore the misogyny. It is a book written by a man about a man's world for men. The "Our' in the title does not include half the world.

The misogny, the putting down of fat women, ugly ones, old ones in this often otherwise insightful and percipient book is making me groan. The a
Sep 20, 2008 rated it it was ok
This book was somewhat entertaining, but I can't really recommend it. The author does experiments with college students and beer, and extrapolates this into a world view. Most of his applications are anecdotal.
Here's an example on p. 215: "Iran is another example of a nation stricken by distrust. An Iranian student at MIT told me that business there lacks a platform of trust. Because of this, no one pays in advance, no one offers credit, and no one is willing to take risks. People must hire with
Oct 09, 2008 rated it it was amazing
It is important that you move this one up your list of books that you have to read. This is a particularly great book. My dear friend Graham recommended I read this book. He has recommended four books to me – and the only one I couldn’t finish was “My Cousin, My Gastroenterologist: A novel” by Mark Leyler – but he did recommend, “The Tetherballs of Bougainville” also by Leyler and that is still one of the most remarkable books I’ve ever read. I haven't written a review of that book, but where th ...more
Ahmad Sharabiani
Predictably irrational : The Hidden Forces That Shape Our Decisions, Dan Ariely

Predictably Irrational: The Hidden Forces That Shape Our Decisions is a 2008 book by Dan Ariely, in which he challenges readers' assumptions about making decisions based on rational thought.

Ariely explains, "My goal, by the end of this book, is to help you fundamentally rethink what makes you and the people around you tick. I hope to lead you there by presenting a wide range of scientific experiments, findings, and
Riku Sayuj
Jul 14, 2011 rated it really liked it  ·  review of another edition
Recommends it for: Nishant Singh
Written in the tried-and-tested and bestselling tradition of the Malcolm Gladwell books and the Frekonomics clones, Dan Ariely's book too is an entertaining and counter-intuitive look at the world around us.

While I am getting more and more inured to this way of analysis of behavioral economics and physchology, these kinds of books are still hard to resist - that is because they do, no matter if they have now become an industry doling out similiar books by the dozens, still stretch our perspecti
Always Pouting
Feb 12, 2017 rated it really liked it  ·  review of another edition
Honestly all the business books that talk about psychological research or behavioral economics talk about the same things. I haven't even read Thinking Fast and Slow by Daniel Kahneman but all these books literally rehash it again and again so I probably wouldn't even get anything out of reading it now. That said this one's much better written than most of the other books I've read and so if you haven't read anything else about behavioral economics or that way we make decisions this is a good ch ...more
As a social psychologist, I have been trained to scoff at all "behavioral economists" because they often claim to have recently discovered that individuals do not always behave "rationally". Furthermore, they seem to brilliantly deduce that the only way to accurately predict how humans actually behave is to test behavior/decision making empirically. Of course, social psychologists have been doing this for over half a century without much public fanfare or guest spots on "MSNBC" or "CNN" every ti ...more
Mar 19, 2008 rated it it was amazing
Shelves: read-in-2008
All classic economic theories are based on the assumption that consumers behave rationally, despite a considerable body of evidence to the contrary. It is only in the last 25 years that economists have begun to investigate the irrational side of consumer behavior. This field of investigation, which started with the pioneering work of Tversky and Kahneman, is usually referred to as behavioral economics.

Dan Ariely's book, "Predictably Irrational", offers a clear and comprehensive overview of thi
Nov 05, 2013 rated it it was ok
Yet another book I'm recommending to Goodreads staff. I will write up a long review when it's done, but I think this is worth chewing on:

According to the author of Predictably Irrational, we live simultaneous in the world of social norms and the world of market norms. Social norms are the exchanges and requests we make as part of personal connections. Market norms are the dollar-defined exchanges of dollars, wages, rents, prices. Here's where it gets interesting:

"In the lasts few decades, compa
May 06, 2011 rated it really liked it

Explores the ability of a decoy option to determine outcomes.
(The economist subscription, travel to rome or france w/free breakfast)

Our first experience becomes our anchor point that future instances are pegged to and rebound towards like a rubber band.

Anchor points are hard to change, but new anchor points can be created wholecloth by giving people a new experience (starbucks vs. dunkin donuts)

The power of FREE! to disguise the actual cost we pay. The difference between 0 and 1 is
Jun 05, 2012 rated it it was amazing
This is a wonderfully interesting and amusing book. Every time I had a few spare minutes, I would leap back into it with gusto. Some of the things I read I had already seen elsewhere - but much was new to me. The author is described as a behavioural economist.....and I think this book would interest anyone who is interested in psychology.

This book is tops. There are enough reviews here singing its praises already. I shall simply end with some notes for my own record(view spoiler)
Jul 15, 2018 rated it it was amazing
What an interesting book. It complemented my last reading ~ Thinking Fast and Slow by Kahneman ~ in some ways. The examples in the book suggests that `The Neo Cortex` is such a funny dude that tricks us into thinking that we are making logical decision, that we are rational beings. In the meanwhile the other machinery that actually makes and executes the decision is pulling our strings. As stated in the book, we are a true Jeckll and Hyde dilemma. Very funny and the joke is on us. ...more
Aug 30, 2017 rated it did not like it
Oh God, what shit. Where to begin?

The simplest start is to take issue with the premise, which is simply that the model of a 'rational actor' as defined in classical economics is ridiculous for two reasons: one because of how irrational we are naturally, but also that the degree of our irrationality is so pervasive as to be testable and demonstrable in a way that studies that prove it are easily replicated. This is good. Data replication is crucial. It's a shame that this stubborn notion of a 'ra
Nov 30, 2008 rated it really liked it
If I had to describe Predictably Irrational using two words they would be "thought provoking." The author is a professor who was injured in an explosion in Israel. He suffered severe burns and 5 years of therapy. He used this "down time" to ponder the why's and how come's of life. Using many experiments he (and others) tested the moral aptitude and other aspects of human behavior.

Each chapter has several experiments that pertain to a topic.

Chapter 1: The Truth about Relativity: Why Everything
Otis Chandler
Absolutely loved this book and all the examples it gives of how we think we are making rational decisions, when in fact we aren't. The book concludes by saying many of these irrational decisions we make are entirely predictable (thus the title of the book), and thus we should as a society do better to factor them in. I would have loved more suggestions of how this could be done, but that was beyond the scope of the book.

This book seems to be a must for anyone studying or dealing with pricing. W
Apr 04, 2008 rated it it was ok
Ariely is a good writer whose book catches onto the _Freakonomics_ craze by taking a look at times when people make different decisions that typical "laissez faire" economic theories would expect. His book is a fairly easy read and does include some surprising results through social-science experimentation.

However, the text is not without its flaws. For instance, some of the breathlessly-reported "surprising" results aren't all that surprising or even controversial. For instance, the effect of
May 07, 2015 rated it really liked it
Predictably Irrational is an entertaining and enlightening read.
The most important lesson I learned from Ariely is the high cost of free. The biggest example is "free shipping." Companies only offer you free shipping to convince you to spend at least the minimum amount to get it. Something to think about the next time I shop online.
Many of Ariely's lessons on psychology were already explained to me in previous books, but that isn't a strike against him. It just shows that maybe humans aren't as
Jul 04, 2008 rated it really liked it
Here are just a few tidbit's I've learned:

-If you're ever going to a bar, trying to score a little bit of lovin', bring a friend who looks very similar to you - only a little uglier. That way you'll look like the ideal candidate, not just compared to your friend but to everyone else there.

-People are more likely to steal things once removed from cash than cash - ie. the Enron crew who stole millions of dollars from the retirement pensions of little old ladies, but would they ever have snatched 1
Mar 22, 2009 rated it did not like it
reads like an extended, slightly dumbed down USA today article.
Jamie Smith
Jul 14, 2021 rated it really liked it
Shelves: science
We like to think of ourselves as rational actors who carefully evaluate our options, and make decisions based on cool, dispassionate logic. Not bloody likely, especially after we’ve had a few drinks. Just ask the author of this book, MIT behavioral economist Dan Ariely. We all come loaded with preconceived ideas and past experiences and can nudge ourselves, or be nudged by those wanting to manipulate us, without our ever suspecting a thing.

This book describes a number of cleverly designed exper
Aug 01, 2008 rated it it was amazing
It's only about the middle of the year, but I think Dan Ariely's Predictably Irrational is a shoe-in for my favorite non-fiction book of 2008. When I was studying psychology one of my favorite topics was judgment and decision-making, which dealt in large part with the kinks in the human mind that could lead us to irrational behavior and decisions. Why are you likely to pay more for something if you are shown a large number completely unrelated to the price? Why do people who read words like "eld ...more
David Rubenstein
Mar 14, 2010 rated it it was amazing
While there is nothing truly new in this book, it is written very clearly and concisely. Unlike some other books of this genre, this book does not ramble on and on about irrelevant subject. The author makes this book a very interesting read.
Salil Kanitkar
Mar 18, 2017 rated it really liked it
Shelves: 2017, english

Whether you are into behavioral economics or not, whether there are better books than "Predictably Irrational" out there or not, it is still a must read I feel. For one, it is less economics and more behavioral psychology (this would be considered good or bad depending on your expectations though). Two, about 50% of the experiments that the Author carries out and talks about at length in the book are fascinating and eye-opening. The rest of them, not so much. Three, the book makes you realize ho
Janet Newport
Jan 01, 2020 rated it really liked it
My final read of 2019... and it was fascinating. An easy, somewhat anecdotal read on behavioral economics. I did see myself in several of the anecdotal examples and recognized my own self justifications for spending money that I later questioned. Who knew I was a goose??

Hopefully some of the self-realizations will carry forward.
Laura Gembolis
Jan 24, 2012 rated it really liked it
There’s a generalization that people make that really gets me. It’s the idea that people naturally prefer or practice competition over collaboration or cooperation. Usually this is said as a way to dismiss addressing inequalities in America and to explain why capitalism is the only choice. Socialism or any hybrid economic system is doomed. Doomed! There are several reasons the acceptance of individual competition over striving for the group’s overall well-being seems to be a social norm rather t ...more
Jun 11, 2011 rated it really liked it  ·  review of another edition
Recommends it for: Malcolm Gladwell and Freakonomics fans
As you can tell from the title, this book gives us a needed reality check when it comes to our belief that we are making rational decisions. Ariely writes engagingly and informatively about the various unwitting errors we make, from finding an option more attractive simply because of its proximity to a less attractive version of it (note to realtors: if you want to sell someone a particular house, show the prospective buyers a similar and slightly inferior one) to overvaluing something because w ...more
Mario Tomic
Sep 20, 2015 rated it it was amazing
I don't think there's one person out there who won't learn something valuable from this book. If you've already read a few popular behavioral physiology books then this book might just help you understand ideas you've already heard about but also introduce a ton of new stuff. The big idea of the book is that irrationality is systematic and predictable, which means that whether we like it or not we are all biased. And we can't help it. The only thing we can do is recognize these biases and potent ...more
Dec 27, 2016 rated it liked it
If the brain is predictably irrational, then the books which warn us we aren’t the rational creatures we hope are also predictable. I don’t think there was a single circumstance in Ariely’s book I wasn’t already aware of from one experiment or another, one summary or another. That said, Predictably Irrational is well written and easy to digest; there’s no technobabble, and everything is presented in a very readable and readily understandable format. It’s not Dan Ariely’s fault that I’ve read all ...more
Chip Huyen
Jul 19, 2016 rated it it was amazing
I read this book per my professor's recommendation. It's not one of the best books that I've read, but it's a book that changed how I perceive the world of abstract irrationalities around me. The way Ariely constructed experiments to measure dishonesty, trust, effects of emotions on our thinking is admirable. ...more
Daniel Pink
Jun 03, 2009 rated it it was amazing
Excellent insights into behavioral economics
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From Wikipedia:

Dan Ariely is the James B. Duke Professor of Behavioral Economics at Duke University. He also holds an appointment at the MIT Media Lab where he is the head of the eRationality research group. He was formerly the Alfred P. Sloan Professor of Behavioral Economics at MIT Sloan School of Management.

Dan Ariely grew up in Israel after birth in New York. He served in the Israeli army and

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