DAN ARIELY

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Are We More Rational Than Our Fellow Animals?

August 20, 2009 BY danariely

We usually accept without argument the notion that man is at the top of the animal hierarchy. After all, only mammals have a neocortex – the most recently evolved part of the brain and the center of higher mental functions – and ours is the most advanced variation, so it makes sense that we’d be at a higher stage of development.

But is this true? Does the neocortex always make us more rational than other animals?

Most of the time, the answer is yes. For instance, it’s thanks to our neocortex that we are able to plan for the future, something that animals have a hard time doing. (They are even worse at saving than we are!)

Still, this isn’t always the case, as the following chimpanzee experiment suggests. In “Chimpanzees are rational maximizers in an ultimatum game,” researchers Keith Jensen, Josep Call, and Michael Tomasello looked into how chimps fare at one of the classic tests of human rationality, the ultimatum game.

In the human version of this game, a “proposer” is handed some money, say $10, and must suggest a division of the sum for himself and another participant. This other person, the “responder,” can then either accept or reject the offer. If he chooses to accept the division, both participants receive their share; if he opts to reject it, neither gets compensated.

Now, if we were to go by the traditional economic model of man as a self-interested rational maximizer, we would suppose that the proposers would always suggest a division that maximized his self-interest (an $9/$1 division) and that the responders would always accept a nonzero offer ($1 may not be $9, but it’s still better than nothing).

Except, this is not what happens. Research has shown that we human beings not only consider how best to maximize our compensation, but we also factor in such notions as cooperation and fairness when we make our decisions. For example, responders in the ultimatum game will often reject a monetary division that is particularly unfair for them (such as a $8/$2 division) – even when this comes at their own cost (they lose the $2, after all). This behavior is of course wonderfully human — but it is not part of the standard rational model.

Chimpanzees, however, go about the ultimatum game (which involves divisions of raisins in their case) without giving fairness any thought. In this experiment, the researchers found that the chimp responders tended to accept any nonzero offer, however unfair. And conversely, the chimp proposers rarely suggested a fair division, choosing instead to maximize their own share.

In this case, then, animals are more rational than we are. Whereas we’re willing to lose a couple bucks so that the other guy gets punished for his inequitable offer, chimps only act according to what will guarantee them the most raisons.

This curious turning-of-tables suggests that we might want to think differently about the neocortex. Overall, we’re better off having it, as without our sense of right and wrong, we would lack empathy and the ability to reinforce societal rules. Yet, in certain contexts, the neocortex can cause us not to maximize our self-interest. Evolution, then, is a mixed blessing: it makes us better some things, and worse at others.

PREDICTABLY IRRATIONAL SHORT STORY SERIES NO. 3

August 15, 2009 BY danariely

It’s time for another Predictably Irrational Short Story! This one is a love story the beautifully demonstrates some of the principles of discussed in Predictably Irrational about decision making applied to dating, again written by one of my students at Duke. It’s called “The Dating Game” and you can find it here.

The Nuances of the FREE! Experiment

August 10, 2009 BY danariely

The New York Times and Time Magazine have recently posted interesting articles about two new books that discuss consumer behavior: Chris Anderson’s Free and Ellen Ruppel Shell’s Cheap (see links in The New York Times and Time Magazine).

Both books reference our Hershey’s Kiss experiment that is described in Chapter 3 of Predictably Irrational. If you recall, in one trial of one study we offered students a Lindt Truffle for 26 cents and a Hershey’s Kiss for 1 cent and observed the buying behavior: 40 percent went with the truffle and 40 percent with the Kiss. When we dropped the price of both chocolates by just 1 cent, we observed that suddenly 90 percent of participants opted for the free Kiss, even though the relative price between the two was the same. We concluded that FREE! is indeed a very powerful force.

It’s important to note that we have carried out lots and lots of studies on the effect of FREE!, many of which are detailed in Predictably Irrational. Describing them all, however, would be too much for those who are trying to make just one point abut this effect, so naturally we see authors making choices about which experiments to describe and which ones to leave in footnotes, or not to mention at all. But, some  kinds of omissions are made as well — ones that are important for understanding the complexity of the effect.

For example, in one study of FREE!, we tried lowering the price from 2 cents to one cent on the Kiss to see if we observed that same level of increase in demand in the Kiss. We didn’t. In another study we also tried seeing what would happen if we lowered the price from FREE! to negative one cent, and we also didn’t see a difference in behavior. We also tried the experiment on a broad demographic–not just college students, but also on children and older adults.
Personally, I think it is perfectly fine for people to take the main point from some experiments and build on it, but as readers (and writers) we should realize that often there is more complexity to the picture and that before criticizing particular findings, or citing them as supporting evidence, we should keep in mind the nuances.

Is Free Bus Fare a Good Idea?

August 5, 2009 BY danariely

Someone should remind Michael Bloomberg that free does not always mean free lunches.

The billionaire New York City mayor recently rolled out a transit proposal that sounds too good to be true – probably because it is.

In order to speed up the pace of Manhattan’s famously slow crosstown buses, mayor Bloomberg suggested eliminating the $2.25 fare on a few of the buses, as it would put an end to all the time passengers spend fumbling for their MetroCard and cash at the bus door. It would mean free bus rides for all, but without much additional cost to the city, he reasoned, since the majority of crosstown passengers are already riding for free, using their MetroCards to transfer from the subway. If we aren’t charging folks anyway, it’s not a big money loss, is the gist of his claim.

In short: win-win.

Except, there’s a flaw to his argument.  If bus fare falls to zero, it’s likely that more people (many more people) will start riding the bus, which will lead to even worse congestion and potentially require the city to spend on introducing more buses.

In other words, mayor Bloomberg is harboring under the assumption that demand for the cross town bus will not change as the price drops. In all likelihood, however, the number of bus-riders will go up dramatically because free is exciting. In fact, according to our research on free, such a change will cause many people who now walk a few blocks, to switch their ways and hop on the free bus.

The Trouble with Cold Hard Cash

August 5, 2009 BY danariely

Motivating people is an extremely difficult and delicate task as anyone who’s ever taught, managed, collaborated with or given birth to someone knows. In business, as opposed to say, child-rearing, the debate is slightly less daunting, though not always much clearer. For instance, offering incentives to employees for improved performance is a fairly common approach to encouraging higher sales —though surprisingly unproven by data.

For the most part, the effectiveness of incentives is supported by intuition and some anecdotal evidence. Wouldn’t everyone work at least a little harder for a $100 bill on top of their usual paycheck? Certainly it can’t hurt. But one important open question is whether monetary or tangible (spa retreat, ipod, dinner for two, etc) rewards more efficacious motivators?

Those who advocate for monetary incentives claim they have the greatest appeal given that the winners can do anything with them; what if someone needs an ipod like they need another hole in their head? On the other side, those in favor of tangible incentives argued that money lacks the emotional appeal of, say, a weekend for two at a romantic country inn or swank hotel. But either way, there was nothing to back up either camp.

Thankfully, there is some data on this debate.  A few years ago Goodyear Tire & Rubber Company decided to test which method was more successful in an effort to improve sales of a new line of Aquatred tires. Their plan was simple and elegant: first they ranked their 60 retail districts according to previous sales, then divided them into two groups of equal performance and assigned one group to receive monetary incentives and the other to receive tangible incentives of equal value to the first group.

The results were very interesting; it turned out that the tangible-reward group increased sales by 46% more than the monetary-reward group. They also improved in terms of the mix of products sold by 37%. One explanation, and it seems to me a fairly good one, is that we can visualize tangible rewards (imagine yourself on a Hawaiian beach), which creates an emotional response. Money, on the other hand, is not accompanied by images as often (aside from maybe Scrooge McDuck swimming in piles of it), and lacks the emotional pull that tangible rewards have, so they’re less effective in motivating employees. I guess it’s called “cold, hard cash” rather than “future beach vacation cash” for a reason.

Predictably Irrational Short Story Series No. 2

August 1, 2009 BY danariely

In a follow-up to the much acclaimed “Pinch of Saffron” , this latest Predictably Irrational Short Story is a thrilling Wall Street tale of overpricing CDOs, again written by one of my Behavioral Economics students, Andrew Holmberg. It’s entitled, “Fixed Income”, and you can find it here.

Introducing the Predictably Irrational Short Stories Series

July 15, 2009 BY danariely

I pleased to announce a new series of short fictional stories written by Duke undergraduate students who took my Behavioral Economics class this last spring.

I will post another one of these stories twice a month for the next few months.

The first story is called “A Pinch of Saffron,” which is about a business executive who redesigns her mother’s traditional Indian restaurant to monetize on people’s irrationalities. You can download it here.

The value of advice (by Alon Nir)

July 10, 2009 BY danariely

A few days ago Dan wrote about Don Moore’s research on how we accept advice from others. A lab experiment showed that subjects adhered to advice from confident, not necessarily accurate, sources. The findings of another research, led by Prof. Gregory Berns of Emory University, show another aspect of our reaction to advice.

Berns recorded his subjects’ brain activity with an fMRI machine while they made simulated financial decisions. Each round subjects had to choose between receiving a risk-free payment and trying their chances at a lottery. In some rounds they were presented with an advice from an “expert economist” as to which alternative they consider to be better.

The results are surprising. Expert advice attenuated activity in areas of the brain that correlate with valuation and probability weighting. Simply put, the advice made the brain switch off (at least to a great extent) processes required for financial decision-making. This response, supported by subjects’ actual decisions in the task, are troublesome, perhaps even frightening. The expert advice given in the experiment was suboptimal – meaning the subjects could have done better had they weighted their options themselves. But how could they? Their brains were somewhat dormant.

References:
Jan B. Engelmann, C. Monica Capra, Charles Noussair, Gregory S. Berns (2009). Expert Financial Advice Neurobiologically “Offloads” Financial Decision-Making under Risk.

We’re Swayed by Confidence More than Expertise

June 25, 2009 BY danariely

“For the great majority of mankind are satisfied with appearances, as though they were realities, and are more often influenced by the things that ‘seem’ than by those that ‘are.'”
-16th-century Italian politician Niccolo Machiavelli

It’s something we come across regularly: presentation trumps content. Often what matters is not what we know, or what we have done, but rather how we spin it. It’s why cover letters are so important, and why the peripheral route to persuasion – one of advertising’s biggest weapons – works.

Now, Don Moore of Carnegie Mellon University demonstrated yet another way that we are heavily influenced by delivery — We tend to seek advice from experts who exhibit the most confidence – even when we know they haven’t been particularly accurate in the past.

In his experiment, Don had volunteers guess the weight of people in photographs, and paid them for their correct answers. But before each guess, the volunteers were asked to choose one of four advice-givers (also volunteers) from whom to buy advice. Each advice-giver submitted their weight guess in percentage form, with some advisers spreading out their advice over multiple weight ranges. So, one advisor might have said that there was a 70% chance that the person’s weight was 170-179 pounds, a 15% chance that it was 160-169, and a 15% chance that it was 180-189. A more confident advisor, however, would have put all his eggs in one basket and said there was a 100% chance that the weight was within the 170-179 range.

Now here’s the really important part: in each round, before they chose their adviser, volunteers got to see each adviser’s percentage spread, but not the associated weight ranges. (See this really handy chart for more on the set-up.)

What did Moore find? Volunteers were more likely to buy advice from confident advisers (such as the 100% adviser from above) than those who spread out their percentages. What’s more, this tendency led advisors to make their advice more and more precise in subsequent rounds – but not more accurate.

These findings are troublesome. Because though confidence and accuracy sometimes go hand-in-hand, they don’t necessarily do so. And when we want confident advisors, some will exaggerate to give us what we want.  Maybe this is why so many pundits on TV for example exaggerate their certainty?

Context effect in Britain’s Got Talent?

June 13, 2009 BY danariely

I got this suggestion from Thomas Aedy in Eton College in the UK:
Dear Dan,

The final for Britain’s Got Talent was on Saturday June 30th and this final was very interesting because it involved 3 choices, 2 of which were very similar, and 1 of which was different. In our show, viewers have to vote in by telephone on the night of the show for a winner to be decided, and there was some shock when the favorite (Susan Boyle – a singer) didn’t win, and lost out to one of two dance groups (Diversity were the winners, Flawless were the other dance group) – whilst the dance group were very good, most people thought that the singer would edge win.

I think this is a case of relativism:

Option A – Singer – Susan Boyle who was generally regarded (before the final) as the favorite contender for the win

Option B – Dance group – Diverstiy

*   Probably the better of the two dance groups – more creativity and flair, and possibly more entertaining
*   That is largely my view, although their victory in the competition would suggest that they were the better of the two dance groups

Option B’ – Dance group – Flawless

*   Also a very talented dance group, but more straightforward dancing – not very many surprises from them
*   We could view them as the ‘dud’ choice of the two (although this is somewhat harsh)

General points

*   Frankly impossible to judge who were the best of all three – all of them were very talented, but it is impossible for most viewers to try and think whether Option B was better than Option A (comparing singing and dancing)
*   However, on the night, it is fair to say that Option B was better than Option B’
*   Thus whilst most found it impossible to establish who was better of A and B – it was clear that B was better than B’, and this made it easier to select an overall winner (which would be Option B)

In my mind this could be seen as an example of relativism

Very best wishes,

Thomas Aedy

PS: YouTube videos of the 3 acts if you’re interested.

Option A (singer) : http://www.youtube.com/watch?v=b2xiAQCTy2E

Option B (dance) : http://www.youtube.com/watch?v=KJIz8BgRQc0


Option B’ (dance) : http://www.youtube.com/watch?v=NY9I6pxnVpM

————-

I did not watch this show — but I find the idea plausible and interesting.

Dan