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Science

The Science of Irrational Decisions 244

Posted by kdawson
from the why-you-do-what-you-do dept.
The Rat Race Trap blog has a look at one aspect of the irrational decision-making process humans employ, based on the book Predictably Irrational by Dan Ariely. "Professor Ariely describes some experiments which demonstrated something he calls 'arbitrary coherence.' Basically it means that once you contemplate a decision or actually make a decision, it will heavily influence your subsequent decisions. That's the coherence part. Your brain will try to keep your decisions consistent with previous decisions you have made. I've read about that many times before, but what was surprising in this book was the the 'arbitrary' part. ... [In an experiment] the fact that the students contemplated a decision at a completely arbitrary price, the last two digits of their social security number, very heavily influenced what they were willing to pay for the product. The students denied that the anchor influenced them, but the data shows something totally different. Correlations ranged from 0.33 to 0.52. Those are extremely significant."
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The Science of Irrational Decisions

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  • Not sure (Score:2, Funny)

    by Anonymous Coward

    I think Im 50 / 50 on this one

    • Re: (Score:3, Funny)

      by node 3 (115640)

      Aha! We now have the last two digits of your social security number...

      Question. If you were to represent your odds of agreeing with this study as a *nine* digit number, what would it be?

  • So (Score:5, Funny)

    by MyLongNickName (822545) on Friday October 23, 2009 @11:36AM (#29846597) Journal

    Will it help me to understand why I read Slashdot instead of doing something productive with my time?

    • Re:So (Score:5, Funny)

      by spun (1352) <loverevolutionary @ y a hoo.com> on Friday October 23, 2009 @11:45AM (#29846695) Journal

      Yes. You arbitrarily decided to read Slashdot one day. In order to maintain internal consistency, your brain had to make it seem like this is a good idea, and continually offers up excuses for reading Slashdot.

      • Re:So (Score:5, Funny)

        by dissy (172727) on Friday October 23, 2009 @01:26PM (#29848139)

        In order to maintain internal consistency, your brain had to make it seem like this is a good idea, and continually offers up excuses for reading Slashdot.

        Pfft, I don't need excuses. I can stop reading Slashdot any time I want!

    • Re:So (Score:5, Interesting)

      by Idiomatick (976696) on Friday October 23, 2009 @11:45AM (#29846705)
      In case you were actually curious which I'm sure you are...

      Humans are naturally curious, and we have a love for information. These are great things, clearly evolving to strive for greater knowledge and understanding is a good thing. And a certain level of curiousity is also good. So there are mechanisms in our brain that reward us for gaining knowledge... generally you feel good learning something.

      That said, the implementation is terrible. We get rewarded (chemically) for ANY information we learn. There is no natural mechanism that filters out useless information. So at our base we feel equally rewarded learning about britney spears' baby as we do about our political system. This results in you feeling good learning the tidbits of information though they may not be very pertinent to your life. If you are good at trivial pursuit you are likely more of an addict and so on.
      • Re: (Score:3, Informative)

        by snowraver1 (1052510)
        I disagree. I find watching E-Daily, or Entertainment Tonight, or any other celebrity show physically nauseating. It's literally an assault on my brain.
        • Re:So (Score:5, Funny)

          by lwsimon (724555) <lyndsy@lyndsysimon.com> on Friday October 23, 2009 @12:09PM (#29846987) Homepage Journal

          You probably do it too much, though, as you obviously have never spent any time with a dictionary. If you did, you would realize that you just stated that certain shows show intent to physically harm your brain.

          Please use the word "literally" literally in the future.

          • Re: (Score:3, Informative)

            by Mr Z (6791)

            You're literally full of it. "Literally" has been used as an intensifier since the 17th Century. [slate.com] Get over it. And before you go off on the author of the article I just linked... He's a dictionary editor. I think he spends more time with a dictionary than any of us.

            • Re: (Score:3, Insightful)

              by lwsimon (724555)

              I appreciate the link, but the improper and confusing use of a word throughout history doesn't make it correct. Even the author of the article you linked decries the use of the word in a confusing manner.

              I really did like the article, though :)

              • Language isn't immutable. If a word is used "improperly" over a great deal of time, it eventually acqires that "improper" meaning.

              • by Mr Z (6791)

                I enjoyed the article too. :-)

                English is full of confusing words. That doesn't make their use improper, it just makes them potentially confusing. I'm inclined to put "literally" in that category. If I said "I dusted the light dusting of dust off the book," aside from being (purposefully) repetitive, is it incorrect? The verb "dusted" means removing dust, whereas the verb "dusting" (used as a gerund) means adding dust. (Somebody cue "Buffalo buffalo..." guy.)

                I do agree with his penultimate advice: "Don

              • Re: (Score:3, Insightful)

                by pugugly (152978)

                For what it's worth - the sentence I abhor is the "Never Assume - it makes an ass of you and me!" bit of obnoxious cleverness, even more annoying than "There is no I in Team!".

                It just irritates the hell out of me, since all logical though is in fact based on *some* set of propositions taken for granted. Euclid is based on one set of assumptions, Riemannian geometries an almost identical set of assumptions. Good thing for both Newton and Einstein Euclid never bought into *that* BS.

                "Never Assume" only seems '

        • Re:So (Score:5, Interesting)

          by causality (777677) on Friday October 23, 2009 @12:18PM (#29847099)

          I disagree. I find watching E-Daily, or Entertainment Tonight, or any other celebrity show physically nauseating. It's literally an assault on my brain.

          That's because such trivia is designed for children who never really grew up. Y'know, the ones who have adult bodies. That's why they think someone else's personal life is so much more fascinating than their own, merely because that person can sing or dance or act. They don't seem to notice that the truly famous entertainers are some of the most out-of-touch people who are least worthy of this kind of adoration. The doctor who finally cures cancer will be an anonymous, unknown figure by comparison.

          They're impressed with the entertainer's ability to entertain and that's their only real criteria; any critical thinking or other evaluation shuts down at that point. Their appetite for the superficial and insignificant is absolutely endless, even though those same mental faculties could be put towards educating themselves, establishing deep and meaningful connections with people like their neighbors, and finding real purpose and meaning in their own lives. They see nothing wrong with this or the waste that it represents.

          It's an assault on your brain because the underlying message is "it's okay to devote so much time and energy to something completely devoid of any real meaning." There's also the implication that it's okay to form grossly asymmetric relationships instead of mutual relationships, that there is anything healthy or nurturing about this, like when a person learns all about the personal and romantic life of an actor when that actor doesn't even know that he or she exists. The message is that you should eagerly do such things merely because it's encouraged by the industry that was built around it. If you have any understanding whatsoever, how could you do anything but reject this notion?

          • Re: (Score:3, Interesting)

            by inviolet (797804)

            That's because such trivia is designed for children who never really grew up. Y'know, the ones who have adult bodies. That's why they think someone else's personal life is so much more fascinating than their own, merely because that person can sing or dance or act. They don't seem to notice that the truly famous entertainers are some of the most out-of-touch people who are least worthy of this kind of adoration. The doctor who finally cures cancer will be an anonymous, unknown figure by comparison.

            Well said

        • Grats, i said 'base'. You have gotten over part of it using logic and processing in your fore-brain. That said, I bet you still listen and remember bits of it even if you find it abhorrent. I'm sure I can list other flaws in your brain if you'd like. I'll go with... procrastination, you don't do things as quickly as you could which is clearly inefficient, were you to design a life you'd likely not have it procrastinate. Unless you were trying to approximate a human.
      • Re:So (Score:5, Interesting)

        by linguizic (806996) on Friday October 23, 2009 @12:34PM (#29847295)
        Studies have shown that 80-90% of everything that humans talk about is gossip. When you think about this from an evolutionary perspective it makes sense. We're highly social animals and our biggest competitors are other humans. Sharing information about the members of tribe is a HUGE advantage. Unfortunately, today we have the same brains that our tribal ancestors did and these brains seem to include celebrities in our tribes, so we eat up gossip about them. The implementation isn't terrible, it's just legacy :)
        • Re:So (Score:4, Interesting)

          by Idiomatick (976696) on Friday October 23, 2009 @12:51PM (#29847545)
          Exactly. The human brain is like a computer program that has constantly been patched for millions of years. The original intent of the program is completely different from how we use it now. And we have never had a version change or rewrite. Oh and we were programmed by inputting code semi-randomly.

          When you think of it from that point of the it isn't at all surprising we have a few hundred stupid flaws.

          I'll let someone else come up with a car analogy if they like.
        • by causality (777677)

          Studies have shown that 80-90% of everything that humans talk about is gossip. When you think about this from an evolutionary perspective it makes sense. We're highly social animals and our biggest competitors are other humans. Sharing information about the members of tribe is a HUGE advantage. Unfortunately, today we have the same brains that our tribal ancestors did and these brains seem to include celebrities in our tribes, so we eat up gossip about them. The implementation isn't terrible, it's just legacy :)

          That makes a lot of sense to me. Before technology allowed anything other than face-to-face communication, such a tendency might have been valuable. You can, after all, be greatly affected by the decisions of those closest to you. However, it seems to break down due to telecommunications. Telecommunications and mass media mean that this mechanism is being used for strangers that the individual will probably never meet. Due to that, it loses the meaningful function of "staying in touch" that it once ser

      • by blue_teeth (83171) on Friday October 23, 2009 @12:53PM (#29847567)
        For better understanding on Dan Ariely's point, see this video http://www.ted.com/talks/dan_ariely_on_our_buggy_moral_code.html [ted.com]
    • Cool. This means that I can stop trying to get my wife to make more rational decisions. At least until someone invents a time machine.

    • Yes.

      It increases Dopamine spikes in your brain. Doing Productive Things is boring, so they don't. It's the same brain center as other addictions.

  • Remember those personalized hologram ads in Minority Report? Now, if they know your SSN, they can personalize a "deal" for you at a price you might be more willing to pay for it.
  • by Red Flayer (890720) on Friday October 23, 2009 @11:37AM (#29846615) Journal
    How the hell did this article make it off the firehose?

    There is a quote in the summary from a blog referenced. The blog is not linked to -- instead the only link is to a site (Amazon, I think) selling the book.

    Where's the actual discussion of what's in the book? Where's the article (or blog entry)?

    If you're going to post a book review... please, include the review. Otherwise it looks like you're just hocking a book.
  • TFA (Score:5, Informative)

    by TubeSteak (669689) on Friday October 23, 2009 @11:39AM (#29846625) Journal
    • by kalirion (728907)

      Editors sleeping on the job

      They were probably asked to write down the last two digits of the SS# as "the number of hours to sleep on the job" during their orientation.

    • by RyoShin (610051)

      The editors were merely following a previous decision. From the first, they never actually edited, so to do so now would be contradictory. It's irrational cohesion. The ad revenue influenced them.

  • Still, GIGO (Score:4, Insightful)

    by MikeRT (947531) on Friday October 23, 2009 @11:39AM (#29846627) Homepage

    Your brain will try to keep your decisions consistent with previous decisions you have made.

    People tend to forget that logic is just a set of rules. If you load it up with bad data, especially data that is driven by pure emotions, you'll rationalize yourself into neat, coherent clusterfuck. The difference between wisdom and intelligence is that the former is an a priori mental filter for bad data, the latter is just raw capacity. That's why a wise person need not follow a life based on reason alone to generally make good decisions.

    • Re:Still, GIGO (Score:5, Insightful)

      by iamhigh (1252742) on Friday October 23, 2009 @11:54AM (#29846819)
      To bring it full circle... you made a logical decision to do x, this sets a rule in your mind that x is true. Once you made x decision, you had no further reason to question that, and you would base many more decisions on that "logical rule". When x is challanged, it would require you to re-think all past decisions that were based on x, which might include who you married, why you took this job, your religious beliefs and other important life decisions.

      Is it any wonder our minds are wired to assume we were right and keep on moving in the same directions? The brain is trying to keep you alive; anything you have done up to this point won't kill you, so why would the brain try to change that? That's why few people really have a life changing moment unless forced upon them by war, death, or other bad things. When the going is good, you will keep going.
      • by Reziac (43301) *

        Or to put it more simply "This worked yesterday, so it'll work today too". Clearly a survival mechanism.

      • Once you made x decision, you had no further reason to question that, and you would base many more decisions on that "logical rule". When x is challanged, it would require you to re-think all past decisions that were based on x, which might include who you married, why you took this job, your religious beliefs and other important life decisions.

        That's not entirely a bad thing, however (which I think is probably the point of your second paragraph). If you had to re-evaluate every decision you ever made throughout your entire life, you would find that never did anything else. For there to be any progress, you must assume that the decisions that lead to where you are currently were good.

        Hindsight may be 20/20, but at some point, you've got to stop second guessing yourself and actually act on your decisions.

      • Re: (Score:2, Interesting)

        by 517714 (762276)

        Our brains are wired this way because as predators, it was more successful to continue chasing the same animal from the herd than to continually change targets who were not already tired from the chase. It predates anything we would likely call logic since this behavior is found in lower life forms.

      • Re:Still, GIGO (Score:5, Interesting)

        by nine-times (778537) <nine.times@gmail.com> on Friday October 23, 2009 @01:16PM (#29847951) Homepage

        What's more, I would say it's very unclear that we'd be able to live, let alone become intelligent, without such irrational assumptions. This is something that people miss a lot when they talk about intelligence and AI: irrationality is part of intelligence.

        Imagine you didn't generally make basic assumptions that your past actions and beliefs were appropriate. Let's say you wake up in the morning and feel a pain in your belly. Well, yesterday and the day before that, you ate a bowl of cereal with milk in it, and that seemed to make the pain go away. But you're not just going to follow habit or assume that it's a good decision. You're going to wake up every morning from now on and try random things. Maybe you'll try scratching your belly with a stick, or maybe you'll throw yourself out the window. How is intelligence ever going to emerge from that?

        People are creatures of habit, and people are mimics. We do what other people around us are doing. We role-play and we follow fads and we talk the way our neighbors talk. We see friends and family and people on TV eating breakfast in the morning, and so we do it too. Our brains then try to tie all of that habit and mimicry up in a nice tidy logical explanation so that we can understand what we're doing, so that we can explain it to ourselves and to others.

    • by Carewolf (581105)

      No, if your logic is internally consistent, it will form a valid base of logic-space and will only lead to correct results. The problem is a lot of people have and defend broken logic. It doesn't matter if you rationalize about emotions or the bible, if you can manage to make it coherent you are right. I do admit that cohorent emotions are hard, and the bible itself is incoherent, but those are just examples.

      • No, if your logic is internally consistent, it will form a valid base of logic-space and will only lead to correct results.

        You still don't get it, just like most people who turn reason into a fetish. A 100% perfect logical system is still dependent on the data that it receives. One of those inputs is raw emotion. Another is instinct. You cannot perfectly control them, and are lucky to just control them most of the time.

        • by Carewolf (581105)

          I don't try to control my emotions or instincts, but that doesn't lead me to think they are related to logic. You questioned logic, but bring up emotions.

          Sure doing the right thing when it feels wrong is hard, meaning they are both factors of decision making. Logic and emotions are still completely unrelated however. The existance of emotions does not invalidate the soundness of logic. There is not even a reason to think that using emotional data would be wrong. Emotions are perfectly correct data about how

    • People tend to forget that logic is just a set of rules.

      Logic is a set of rules, or more truly a class of rulesets. It can be applied usefully or poorly.

      If you load it up with bad data, especially data that is driven by pure emotions...

      How can data be driven by emotions? I'm not sure I even understand what you're trying to say.

      Logic works very well when applied as a formalized method for decision making. It helps to mitigate some of the emotionally driven flaws in decision making. Logic can also be used, after the decision, as a way to provide a reasonable sounding justification for why a decision was made. For pretty much everyone I've ever m

    • by causality (777677)

      Your brain will try to keep your decisions consistent with previous decisions you have made.

      People tend to forget that logic is just a set of rules. If you load it up with bad data, especially data that is driven by pure emotions, you'll rationalize yourself into neat, coherent clusterfuck. The difference between wisdom and intelligence is that the former is an a priori mental filter for bad data, the latter is just raw capacity. That's why a wise person need not follow a life based on reason alone to generally make good decisions.

      "On two occasions I have been asked, 'Pray, Mr. Babbage, if you put into the machine wrong figures, will the right answers come out?' I am not able rightly to apprehend the kind of confusion of ideas that could provoke such a question."

      -- Charles Babbage

  • "A man hears what he wants to hear, and disregards the rest."
    - Paul Simon, The Boxer

  • Yard Sales (Score:3, Interesting)

    by dschmit1 (1353767) on Friday October 23, 2009 @11:48AM (#29846737) Journal
    This is exactly why I never buy anything that is not previously labeled with a price. I will negotiate but not if I have to contemplate a starting value myself.
    • Which is why car salesmen almost always open negotiations with some variation of "name me a price."

      • by Aladrin (926209)

        Am I the only one that names a really low price when people do this? It's not a thrift shop, it's a car dealership. I always feel insulted when people do this.

        On the other hand, at a thrift shop, yard sale, or flea market, I feel obligated to haggle. And if they don't give at all, I generally don't buy.

        • Re: (Score:3, Funny)

          I do. And when they start to explain why it costs $30,000 more then my offer I go "Well why didn't you say it costs $30,001 in the first place?"

    • by neo (4625)

      Just out of curiosity, what is your social security number?

    • I bet you're one of those jerks who started haggling on the $1.50 ceramic frog from my last yard sale.
  • Anchoring (Score:5, Informative)

    by INeededALogin (771371) on Friday October 23, 2009 @11:51AM (#29846773) Journal
    Nothing really new here. Decisions making based on anchors is a large part of why we use Planning Poker [wikipedia.org] when doing our estimations. All it takes is that one guy that says everything is easy to influence everyone's brain to under-estimate a project.
    • > All it takes is that one guy that says everything is easy to influence everyone's brain to under-estimate a project.

      Not exactly.

      What TFA says could be translated like:

      YOU analyze some (software?) project, and decided (maybe correctly or not) that this is easy.

      Next you analyze other totally unrelated task, for example, running 2 km, and you will more probably underestimate the effort (and the other way too.)

      It's some kind of auto-suggestion with an interesting prove of correlation.

  • The implications (Score:2, Interesting)

    by AdmiralXyz (1378985)
    Our brains favor consistency over correctness... we're finally coming close to understanding the biological origins of conservativism. Here's hoping this research eventually leads to a cure.
    • After all, why would we want engineers designing bridges to be conservative about safety margins?

  • by crmarvin42 (652893) on Friday October 23, 2009 @12:08PM (#29846977)
    Apparently I'm in a very pedantic mood today.

    Correlation is a measure of how well the model describes the data. So according to the summary, 33 to 52% of the variation in the data was explained by the model. Depending on the inherent variability in the criteria being evaluated, that could be very good or very bad. In my line of work that would be very bad, but for social sciences such as sociology, that is very high. It all comes down to how many variables you can control. The more control, the less variation, the higher the correlation when the model is a good fit.

    Significance is a measure of the probability that the response seen is due to random variation or errors in sampling. They may have given a measure of significance in the article, but the summary did not.
  • So, it is basically about cognitive dissonance? [wikipedia.org]

  • Windows (Score:2, Funny)

    by SnarfQuest (469614)

    In other words, a company that installs Windows on its first PC will probably install it on thousands of additions, instead of installing Linux on hundreds.

  • Laziness and Pride (Score:5, Insightful)

    by Temujin_12 (832986) on Friday October 23, 2009 @12:37PM (#29847349)

    To me laziness and pride are the two biggest obstacles to rational thinking.

    Laziness since, more often than not, simply sitting down and thinking things through you can avoid most irrational decisions. Time constraints can make this difficult. But I'm surprised at how often I see family/friends make poor decisions simply because they don't know how to stop and think. I like this quote from Samuel Johnson since it articulates the fact that easy access to information does not mean people will spend the energy to even look at it (let alone use it wisely):

    Mankind have a great aversion to intellectual labor; but even supposing knowledge to be easily attainable, more people would be content to be ignorant than would take even a little trouble to acquire it.

    Next to laziness, is pride. This boils down to the fact that culturally we're often taught to focus on being right rather than focusing on what's right. This comes from the illusion that one can own or control truth. I've seen this affect friendships, marriages, professional atmospheres, politics, etc. Truth is independent. You either align yourself with it or continue to live in ignorance. Of course, objective indisputable truth is rare or even non-existent in humanity, but it's the honest, humble desire to align oneself with truth (not the other way around) that's important here.

  • by threaded (89367) on Friday October 23, 2009 @12:38PM (#29847363) Homepage

    The wife's number ends in 99, which explains everything.

  • When a store puts a product on sale, and it gets a new customer, it also loses that customer when the sale is off? Interesting that a number sticks so hard, not just the relative scale.
  • Hey, I can be a quack evolutionary biologist too! The mind is constantly trying to cast objects and phenomena into patterns, so that it can identify similar patterns of events that happen in the future. That way, it'll have some idea of how a certain decision turned out in a situation patterned a certain way. So naturally, it doesn't just describe or identify patterns, it also constructs them. So by trying to construct the coherences described in the TFA, it is trying to construct a world in which it has an

  • I'm pretty sure advertisers already know this: "How much would you pay for all this? $100? Guess again! If you call within 10 minutes we'll sell it to you for ONLY $19.99!"

  • A Couple Small BS's (Score:3, Interesting)

    by DynaSoar (714234) on Friday October 23, 2009 @02:15PM (#29849011) Journal

    "something he calls "arbitrary coherence."

    And that other call things like behavioral persistance, behavioral momentum, priming, avoidance of cognitive dissonance, etc. He can call it whatever he wants, but that's not going to make the concept his.

    "Correlations ranged from 0.33 to 0.52. Those are extremely significant."

    Those are correlations, the magnitude and direction of co-variance of two measures. These are positive so they vary the same directions. Correlations, are often done using Pearson's technique and are then given the variable little r. A handy but of work with r is the ability to tell at a glance just how much of the observed variance can be explained by the scores. To do so, simply square them. So the amount of variance explained in these tests are 0.11 to 0.27 (11% to 27%). That means from 73% to 89% of the observed variance is unexplained. In practical terms, that's poor. I know in psychology we tend to accept such low r's as meaningful, but we're about the only ones.

    As to "significance": there is no such thing as "highly" (or any other modifier) significant. The significance score, using the variable little p, is what it is, whether you have a program tell you it's equal to or less than a number calculated from the data, or you calculate it and find it to be less than some arbitrary cut off value. If p 0.001 or if p = 0.9, that is the significance level. You can't use the modifiers because significance depends on things like the number of subjects and/or samples, score variance, multiple comparisons between scores, etc. The significance changes. Even with the same data set, if you calculate a second result, you're doing a second comparison which requires a correction factor and that changes p. What significance means in one data set (how many times Mary punches the Bobo doll after watching Homer choke Bart) has nothing to do with another (how many meters depth on average the Earth's surface would be sterilized by all US vs. all Russian thermonuclear weapons), so some dangling, arbitrary "much much MUCH so" means even less, being of zero import but incorrectly suggesting there is.

    So those (.33 to .52) are the r values, In calculating them p was also. It should have been reported. I have no idea of the author ever did or not because the references here consist of two blog posts about the guy's work and one about a book on this subject, and zero that I see on peer reviewed journal articles. Now, I'll be the first to tell you that last bit doesn't count for near what people think, but at least they see to it the formulae are followed, one being proper (as in APA format) quoting of statistics. I might have looked up an article to see if the author gets it right, but I'm not about to read a book by someone who either ignores or is ignorant of the fact that the concept he's examining has already been, in much greater depth and clarity than what's given here.

    • Re: (Score:3, Interesting)

      by ceoyoyo (59147)

      There is a difference between something that is "highly" significant and something that is "barely" significant or "almost" significant.

      The p-value is a measure of the probability that the result could be obtained by chance. Taking the conventional threshold (p=0.05) for significance, you might well say that a result where p=0.05 is "barely" significant, p=0.06 is "almost" significant and p=0.000000001 is "highly" significant. Those adjectives do have meaning, albeit a fuzzy one that should never be subst

  • by kklein (900361) on Friday October 23, 2009 @11:55PM (#29854099)

    Just want to point out that even though the correlation coefficients are definitely significant, that isn't effect size. Squaring the coefficients will give you a better idea of the size of the effect we're talking about here. In this case, the effect was found to account for about 11% to 27% of the shared variance. This is certainly nothing to sneeze at, but it also doesn't mean that you can really bet on it.

    I'm not one of these "social science isn't science" trolltards. I just like to remind people to think in effect sizes to temper their enthusiasm. This is interesting stuff, no matter what, but having a couple quick 'n' dirty formulae for calculating effect size in your mental pocket will keep your reality check intact.

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