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  • PROFESSOR ROBERT SHILLER: OK, good morning.

  • So, I wanted to talk today about Behavioral Finance or

  • about Psychology and Finance.

  • This is a longstanding interest of mine.

  • I've been involved with it for over 20 years.

  • It's not really emphasized in your textbook, Fabozzi and his

  • co-authors talk about a lot of things in the financial world,

  • but not about the underlying human behavior.

  • Behavioral Finance, or Behavioral Economics more

  • broadly, is a kind of revolution that has occurred

  • in finance and economics over the last 20 or 30 years.

  • And it remains somewhat controversial.

  • I don't quite fully understand why it is that people polarize

  • as much as they do, but some people don't like this.

  • We're coming along to be the majority, I think.

  • People are now regarding Behavioral Finance as an

  • important element of finance.

  • But the real problem is that people are complex and our

  • financial institutions, as I've emphasized, are designed

  • for real people and their functioning depends on the

  • behavior of real people.

  • And it's not as simple.

  • You know, another revolution that's occurring parallel, of

  • bigger significance, is a revolution in neuroscience

  • about the human brain.

  • And the human brain is a very complicated organ.

  • Economists have liked to invoke the principle of

  • rationality as an underlying component of their theory, and

  • that has been useful, but it's of limited use, because people

  • aren't rational.

  • They are often rational, they're

  • not completely rational.

  • And very often, people behave stupidly.

  • I'll put it that way.

  • That includes everyone, including me, because we're

  • human and we have limits.

  • One thing about the human species is that we are aware

  • of other people's weaknesses and have an

  • impulse to exploit them.

  • So when you see other people behaving stupidly, sometimes

  • you think, maybe I can turn this to my advantage.

  • OK?

  • And that becomes a problem.

  • The history of humankind is a history of exploitation of one

  • person by another.

  • Not entirely, but I'm saying it has that as

  • an important element.

  • So, I'm going to talk about these human failings.

  • It's not to say that people are stupid, I'm just saying

  • they're people, and we're all imperfect.

  • We're smart in some dimensions and we can be very smart, but

  • we can also make important mistakes.

  • But before I start, I wanted to try to put this into a

  • perspective.

  • Maybe, I'll return to this at the end of the lecture, but I

  • wanted to start out on an upbeat note.

  • I'm going to talk about all kinds of human errors, but I

  • wanted to start on an upbeat note that the business world

  • generally doesn't exploit people terribly.

  • I believe that very characteristically successful

  • businesses in finance and elsewhere consider their

  • long-term advantage and the reputation they have. So,

  • doing something that is blatantly exploitative of

  • human weaknesses will work against

  • their long-term advantage.

  • You'll see a lot of human failings, but we don't see

  • people cashing in on them as often as you'd think.

  • And beyond that, I want to emphasize also that another

  • aspect of human behavior is morality.

  • Evolutionary biologists think that this evolved along with

  • our other traits, that we have an impulse to be moral.

  • And so, in the long run, you might not really gain so much

  • satisfaction from exploiting other people's mistakes.

  • And so, you don't necessarily do that.

  • So, that's why we have a lot of weaknesses outlined and we

  • won't see significant or serious exploitation of them

  • as characteristic.

  • Now as you know, I have chapters from my forthcoming

  • book assigned for this course.

  • And I looked back on what I put up for you to read and I

  • keep thinking, gee, this really wasn't ready.

  • So, I had a chapter for this section of the reading list

  • about Behavioral Finance.

  • And I thought, I didn't really get it right.

  • I know what I was trying to say, but maybe I should --

  • what I start out in that chapter is talking about Adam

  • Smith and his book The Theory of Moral Sentiments.

  • Now just to remind you, Adam Smith was a professor in

  • Scotland in 1759.

  • He was a professor of moral philosophy, because there were

  • no professors of economics in those days.

  • And he wrote in 1759 --

  • Maybe I should write some of this on the board. --

  • He's probably the most important figure in the

  • history of economic thought.

  • So, in 1759 he wrote his The Theory of Moral Sentiments.

  • And in 1776, he wrote the more famous book,

  • The Wealth of Nations.

  • So, this is The Theory of Moral Sentiment.

  • The Wealth of Nations is considered the first real

  • treatise on economics and it's a wonderful book.

  • And it's still very readable today.

  • His The Theory of Moral Sentiments is

  • not so widely read.

  • But it's not really economics, it's a book about psychology

  • and morality.

  • I find it very good, even 250 years later.

  • He went through many editions on this book, because maybe he

  • thought it was his most important work.

  • But the book starts out about selfishness and altruism.

  • And the real question, which he thinks defines economics,

  • is, are people really completely selfish?

  • Sometimes it seems that way, that their presumed

  • benevolence is just an artifice

  • for their own benefit.

  • But he wonders, how does an economy work if everyone is

  • totally selfish?

  • And he ends up concluding that they're not.

  • I thought it was very interesting,

  • the way he put it.

  • The thing he emphasized right at the beginning of the book

  • is that people inherently love praise.

  • We crave the approval of other people.

  • And so, praise is a fundamental human desire.

  • But then he reflected on it and he said, do people really

  • want praise itself or is it something else that they want?

  • Well, think of it this way.

  • Suppose people made a big mistake and thought that you

  • had accomplished something, but there was a mix up.

  • You know, it was really somebody else

  • who did it, not you.

  • And it's just a complete mistake.

  • You had nothing to do with it, but you find lots of people

  • praising you.

  • Would that really be pleasurable?

  • And suppose you even know that they'll never find out that I

  • didn't do it.

  • Well, Smith said, it probably isn't.

  • Think about it.

  • You internally are thinking, I'm getting all this praise,

  • but I know I don't deserve it.

  • So, I don't enjoy it.

  • And then he went on to say that, especially among people

  • who are more mature, he says more mature people --

  • not everyone makes this step.

  • But he says, adults, normal, mature adults, make a

  • transition from a desire for praise to a desire for

  • praise-worthiness.

  • I want to know that I am the kind of person who will be

  • praised and I don't need to get the praise.

  • And he said, it's that tendency ultimately, which

  • makes an economy work, that people don't

  • care just about praise.

  • He gives an example of mathematicians.

  • And he said he's known many mathematicians in his life and

  • he finds that they're almost all obscure.

  • The public doesn't know about mathematicians.

  • They couldn't explain to the public what they do.

  • And they don't seem to care at all, because they know the

  • public doesn't appreciate mathematics.

  • And so, there's a few mathematician friends who

  • understand what they do and may praise them.

  • But ultimately, a mathematician can sometimes do

  • the work completely unknown.

  • And it's the praise-worthiness that drives these people.

  • You may think I'm being too idealistic, when I say this,

  • but I think that the finance profession --

  • this is what I was trying to say in that chapter.

  • That the finance profession, like other mature professions,

  • is really dominated --

  • although there's a lot of funny things that happen.

  • It is really dominated by people who have reached this

  • desire for praise-worthiness.

  • And so, you're not going to exploit people extravagantly.

  • Just because, why would I do that?

  • This is not a good thing.

  • I wouldn't feel good about it.

  • Well, some people will.

  • Now, I wanted to also mention, not everyone reaches this

  • mature state that Adam Smith describes.

  • And that's one of the complexities of human society.

  • And I think that the finance profession has a problem with

  • other kinds of people.

  • Now there's a whole branch of psychology called Personality

  • Psychology that categorizes people by their personality.

  • And we're not all the same.

  • And in our society, we have many different kinds of

  • personalities.

  • A successful society promotes people up who have the

  • praise-worthiness desire.

  • We try to recognize them and we try to put people of

  • character into important positions, with

  • not complete success.

  • But I wanted to just briefly talk about --

  • this is a lecture on psychology.

  • I wanted to talk about other personality types.

  • And I was going to use a book called The Diagnostic and

  • Statistical Manual Edition IV published by the American

  • Psychiatric Association.

  • They're coming out with a fifth edition in 2014.

  • DSM-IV is kind of a household word around my house, because

  • my wife is a psychologist. DSM-IV is actually

  • controversial among psychiatrists, because it's

  • too cut and dry for some of them.

  • What it tries to do is, identify mental illnesses and

  • personality types in a quantifiable, reproducible

  • way, so that we can define who has this mental illness or who

  • has this personality type.

  • And so, it gives you checklists and it says, the

  • patient must have exhibited at least three of the following

  • five behaviors.

  • And then, there will be another checklist. And so, you

  • keep score and you can actually

  • diagnosis personality disorders.

  • I'm just going to mention one of the

  • many personality disorders.

  • One of them is called APD, called

  • Antisocial Personality Disorder.

  • And so they have checklists, but just to

  • give you a sense --

  • oh, and the Antisocial Personality Disorder is called

  • psychopathy, or one kind of APD is psychopathy.

  • Another one is called sociopathy and --

  • I don't know.

  • There's a huge literature on these.

  • But according to DSM-IV, 3% of the male population in the

  • world is APD, and 1% of the female population.

  • A simple definition for APD is a jerk.

  • There are more male jerks than female jerks, apparently,

  • according to their --

  • this is all quantifiable and done.

  • But what is an Antisocial Personality Disorder?

  • It has the following characteristics: lack of

  • remorse, frequent lying, lack of empathy, superficial charm,

  • shallow emotions, distorted sense of self, constant search

  • for new sensations.

  • Have you met someone like that?

  • You probably have, because that's 3% of the population.

  • I'm not anti-male, when I point out there are three

  • times as many jerks among males as females.

  • Females have characteristically different

  • personality disorders.

  • And you can look down the list. It's much more than 3%

  • of the population that would be diagnosed

  • with one or the other.

  • So, you know, an APD person is manipulative, feigns

  • affectionate or warm feelings, but doesn't feel them, and is

  • trying to deceive you.

  • Once a student came to my office and asked to sign up as

  • my research assistant.

  • I was talking and I thought, well, maybe.

  • I said come back and talk to me.

  • Later on, I read about him in the Yale Daily News.

  • He was an impostor student.

  • He was not a Yale student.

  • And he had been around to other university campuses.

  • He was an impostor at like three different campuses.

  • There was something wrong with this person.

  • Kind of made me feel -- then he came later and asked me for

  • a recommendation letter.

  • I couldn't believe it after I read about him in the Yale

  • Daily News.

  • This is extreme.

  • And so, incidentally, someone did a study of APD by going to

  • a prison and categorizing the inmates

  • using DSM-IV standards.

  • And they found that 40% of the prisoners had APD.

  • Also, neuroscience people have found that there are

  • differences in the prefrontal cortex that are

  • correlated with APD.

  • So it seems to be --

  • it's a problem we have in our society that some people have

  • a brain structure that's a little different.

  • And it may make it difficult for them to

  • behave in a good way.

  • We're learning more and more about neuroscience.

  • It's interesting to me that Adam Smith's book still rings

  • true though after --

  • There's some basic common sense that we all learn.

  • You have to judge people and you have

  • to learn their character.

  • And you have to be a person of character for, in the long

  • run, that's what you want.

  • It gives you what you want in life.

  • Oh, another thing I wanted to say is that people are

  • manipulable.

  • Unfortunately, true.

  • And unfortunately, we live in a world where it's hard to

  • avoid manipulating people at all, because we have a free

  • enterprise system that encourages competition.

  • And if the competition is manipulating people, how do

  • you completely stay clear of that?

  • I think, this is one of the contradictions of our society.

  • A very simple and obvious manipulation is, they'll put a

  • price on some item they're selling, like $9.99.

  • So you're like, well, why didn't they just say $10.00?

  • Well, you know why they didn't.

  • It's called ''pricing points'' in marketing.

  • Because $9.99 sounds a lot less,

  • psychologically, than $10.00.

  • So, everyone does it, almost everyone does it.

  • But is that bad?

  • Well, it's bad in a way.

  • It's manipulative, isn't it?

  • I mean I'm annoyed by it.

  • Maybe you are, too.

  • But if you were in business, would you do that too?

  • You might feel that you have to and it's a harmless sort of

  • manipulation.

  • It's not hurting anyone really.

  • They're maybe buying a little bit more than they want.

  • See, that's the kind of thing that comes in.

  • So, in looking at financial institutions, they're often

  • manipulative in that sense.

  • It's similar to a politician.

  • If you want to be a member of Congress or whatever, you

  • can't say what you really believe.

  • Because you won't get elected.

  • You've got to kind of doctor your opinions

  • to the public opinion.

  • But you might have a moral purpose underlying it all,

  • because you want to get elected so

  • you can do good things.

  • So, you do end up saying things.

  • So, it's hard to judge people, good or bad.

  • It's an overall sense you get of someone's character.

  • That people are doing things that appear somewhat

  • manipulative and somewhat bad, but you get an overall sense

  • of the person through time.

  • And ultimately, our society, within limits, rewards people

  • that show character through all the confusing details.

  • Now I wanted to move -- that was my introduction.

  • I wanted to move now to discussing some particular

  • aspects of Behavioral Finance, or more

  • broadly Behavioral Economics.

  • And about human failings that are exploitable by somebody

  • and are somewhat exploited, but remain.

  • I wanted to start out with what's probably the most

  • famous element of Behavioral Economics.

  • It's Prospect Theory and it was invented by two

  • psychologists, Daniel Kahneman and Amos Tversky, in the late

  • 20th century.

  • They called it Prospect Theory because it was a theory of how

  • people form decisions about prospects.

  • And a prospect is a gamble.

  • It's about people's decisions under uncertainty.

  • And in very simple terms, the Prospect Theory says --

  • now there's a huge literature on this, so I'm trying to give

  • you a very quick description of it.

  • That there's something called a value function, which

  • represents how people value things.

  • And there's a weighting function, which shows how

  • people infer or how they deal with probabilities.

  • And I just wrote simply what Kahneman and Tversky say.

  • I'll draw a picture of the value function and the

  • weighting function.

  • And this will be very quick and you'd have to read more,

  • but the way people value gains or losses --

  • let me see.

  • I better draw the line in the middle.

  • OK, and we're talking about financial gains, so these are

  • gains, and this is zero, and this is losses.

  • Well, negative.

  • What I have on the horizontal axis is wealth or money or

  • something like that.

  • Zero in the middle.

  • And then, we have on this axis value, which is

  • something like utility.

  • I'll erase my zero, so it doesn't get in the way.

  • What they find is, that people's

  • value has a funny shape.

  • We don't weigh gains and losses linearly.

  • In the positive quadrant, when we have positive gains,

  • there's diminishing value like that.

  • It doesn't ever slope down.

  • It's concave down like diminishing marginal utility

  • in economic theory.

  • But for losses, it looks something like this.

  • It's concave up.

  • I'm exaggerating a little bit, but this is a diagram that

  • Kahneman and Tversky wrote in their famous Econometrica

  • article 30 years ago.

  • So, there's diminishing marginal utility for gains,

  • but there's the opposite --

  • well, we have concave up.

  • And there's a kink.

  • Note that the value function has a kink at the origin.

  • So, what does this mean?

  • OK, first of all, this origin is a --

  • from what point do I estimate gains and losses?

  • That's called the reference point and it's psychological.

  • And it's subject to manipulation.

  • The reference point is the zero, from

  • which I measure things.

  • So, first of all, the reference point is probably

  • today's wealth.

  • But it can be something else if people are manipulated by

  • the way something is presented to them.

  • Framing, according to Kahneman and Tversky, is presentation.

  • So, I can give the same prospect to people, but word

  • it in different ways that suggests a

  • different reference point.

  • And that will change people's behavior.

  • So, you can manipulate people by describing something in

  • different terms, by suggesting a different reference point.

  • But typically, the reference point is today's wealth.

  • The kink means that people are very conscious of little

  • changes in their wealth and they're spooked by them.

  • I'm really afraid, because my value drops very rapidly, even

  • for a small loss.

  • So, if you were to say, lose $5 this morning.

  • You had it in your pocket and you lost it on the way to this

  • lecture, you would feel exaggeratedly bad about that.

  • You should really regard $5 as just nothing, because the

  • present value of your lifetime income is in the

  • millions, so what's $5?

  • But you don't think that way.

  • So, you're spooked and deterred by small losses, and

  • less encouraged by small gains.

  • So, this kind of thing allows businesspeople to exploit

  • people if they want to.

  • If people are so focused on these little changes, then you

  • are encouraged in business to try to pick things out the

  • people are paying attention to, like small things, and

  • sell insurance policies on just those things.

  • Insurance should be concentrated on the really big

  • things, like life insurance.

  • You know the fact that one of your parents could die and the

  • children's family would be out of money for the

  • rest of their lives.

  • That's a big thing.

  • But it may not work to sell that kind of insurance.

  • You can do something that is more focused on what people

  • are watching and make it something little so that it

  • doesn't require them to spend so much money.

  • The classic example of that is funeral insurance.

  • You go around telling people -- and for some reason this

  • sales pitch works, and it's worked for thousands of years.

  • They sold this in Ancient Rome.

  • You tell people, if someone in your family dies, you can have

  • an expense of getting a proper burial for this person.

  • It costs money.

  • And so, they would insure that one thing.

  • And it was a little thing, but it works to sell that.

  • Another example of it is airline flight insurance.

  • You're insured for this flight on the airplane.

  • I heard an ad for funeral insurance recently.

  • They're still doing this after 2,000 years, because it still

  • works and it's manipulative.

  • That's not what you should do for people.

  • You should not pick out some little thing.

  • Or they also have diamond ring insurance.

  • After an engagement, some women will want to buy an

  • insurance policy on the diamond, because it can

  • actually fall out of your ring and you lose it.

  • But that's like, what is it? $5,000 or something?

  • It's not big, it's not essential.

  • And if you're insuring that and not other things, you're

  • making a mistake.

  • Fortunately, the insurance industry is not too --

  • it has come around to do things that are more --

  • they are doing things that matter and are big.

  • And that's because this Kahneman and Tversky value

  • function is --

  • it represents an error that people are prone to be making.

  • But it's not total and not complete.

  • And so ultimately, people don't go to insurance

  • companies that manipulate them.

  • It gets around and eventually people come around in wanting

  • something better.

  • So, while there is some manipulation, it's limited.

  • The other aspect of Kahneman and Tversky is

  • the weighting function.

  • I'm going to draw again a picture of it.

  • This time it's how people psychologically think about

  • probabilities.

  • This again is Kahneman and Tversky.

  • A probability is a number between 0 and 1 or 0 and 100%.

  • I'll put 0 here and 1 here.

  • We can tell someone the probability of something, but

  • they can't accept it psychologically.

  • The errors that people make are described by

  • the weighting function.

  • What the waiting function is, it's the psychological impact.

  • You are behaving as if you just don't understand the

  • probability.

  • So, what Kahneman and Tversky say is, that for very low

  • probabilities people may round them to zero.

  • And for very high probabilities, they may round

  • them to one.

  • But if they decide not to round them to zero or one,

  • they exaggerate the difference between zero and one.

  • You just can't think in terms of a continuum of probability.

  • So, this is what the weighting function --

  • this is the weight as a function of the probability.

  • For low probabilities it's zero.

  • I'm going to maybe exaggerate it here.

  • Then it jumps up.

  • It's something like this, and as it gets close to one, it

  • jumps up to one again.

  • So you see, it's like a broken line segment.

  • And there's been various versions of this theory, but

  • this is the simplest version of it.

  • So that means, if you're getting on an airplane, you

  • think, well, what's the probability of

  • this airplane crashing?

  • Well it's probably something like 1 in 10

  • million or, what is it?

  • Even less than that.

  • So most of us, in our mind, just say, it's

  • zero and I'm done.

  • I'm not going to think about.

  • I'm not going to worry about it.

  • So, we're down here.

  • We've rounded it to zero.

  • But some people don't round it to zero.

  • And for them, they just blow it out of all proportion in

  • their minds, and it becomes exaggerated.

  • So, I have it here, so it looks like it's a half.

  • This would be one here and this is about 0.4.

  • And then ultimately, if the probability gets really high,

  • then I'm not even going to think about it, it's one.

  • In some of the most primitive languages in the world,

  • there's only a couple of numbers.

  • There's zero.

  • There's one.

  • Maybe there's two or three, and then

  • there's no more numbers.

  • Well, our minds are still very primitive in dealing with

  • probability.

  • So it's like there's only three probabilities.

  • Can't happen, may be, and will happen.

  • So, I think airline flight insurance is an example of

  • trying to manipulate this personality characteristic.

  • So, it means that they'll catch all the people who

  • exaggerate it.

  • They used to have vending machines outside of airlines.

  • The vending machines would encourage you to buy just for

  • this flight.

  • They put it right there when you're getting on the flight.

  • And so that's when you're most nervous.

  • If you're one of these people who's up here.

  • And of course, most people don't buy it, but they don't

  • have to sell it to everybody.

  • They just sell it to these people and they charge an

  • outrageous price.

  • But I haven't seen these vending machines anymore.

  • This is interesting.

  • Economists wrote about them 30 or 40 years ago and they used

  • to be everywhere.

  • And they just kind of disappeared --

  • Do you ever see one of these?

  • I think they're gone.

  • Why is that?

  • Well, somehow we get past things like that.

  • It's not like Kahneman and Tversky are representing

  • immutable errors.

  • These are errors that naturally happen.

  • But you can get past it.

  • And you end up wanting to deal with people you trust. So, you

  • see some vending machine at the airport and you think,

  • well, my insurance agent isn't recommending I get this.

  • I've got some kind of insurance.

  • So, you walk past it.

  • There's a professor in Germany at the Max Planck Institute in

  • Berlin, Gerd Gigerenzer, who has been taking on Kahneman

  • and Tversky in saying that they're right that people show

  • these tendencies for errors.

  • But I can train people out of them with no problem.

  • I just tell them this is an error, and teach them then,

  • and they don't do it anymore.

  • Gary Gorton just did a seminar here on errors that people

  • make in financial --

  • No, Nick Barberis here at SOM, and he was using Caltech

  • students and found that --

  • and tested their ability to prevent certain kind

  • of errors like this.

  • And he found that even the Caltech students made these

  • errors just horribly.

  • We're wondering, aren't they supposed to be bright?

  • Those are young math geniuses.

  • But about a third of them got everything right.

  • So I'm thinking, you know, they're only undergraduates.

  • By the time they get along, if they go -- they'll eventually

  • be trained out of these errors.

  • But right now, they're behaving just like Behavioral

  • Finance says they will.

  • So anyway, I think that you will find that Prospect Theory

  • explains a lot of things that go on in finance, but it

  • doesn't explain everything.

  • And let me move on.

  • So, we want to talk about --

  • let me see.

  • I have got so many things to tell you about here.

  • And I'm thinking about my time.

  • It's a huge field, Behavioral Finance.

  • Let me mention a few other things.

  • Regret Theory is a theory that --

  • it's kind of related to Kahneman and Tversky.

  • It says that people fear the pain of regret.

  • There's an old expression.

  • "I was kicking myself," because I

  • made some bad decision.

  • Well, that's a painful experience when you did

  • something wrong.

  • This is represented somewhat in the kink in the Prospect

  • Theory value function.

  • But Regret Theory says that there's actually a painful

  • emotion, that you're wired not to like

  • to have made a mistake.

  • And so then, you end up designing your life around

  • that and trying to avoid doing anything that you

  • might regret later.

  • And it can create problems. You may make bad decisions,

  • because you're overly worried about regret.

  • Gambling behavior.

  • Anthropologists have reported that gambling occurs in every

  • human society.

  • And so, it's one of the human universals.

  • Not that everyone does it, but in every society you'll find

  • people that do it.

  • I have a 1974 study.

  • It found that 61% of U.S. adults actually gambled at

  • least once for money in that year.

  • I bet, it has gone up.

  • There's more opportunities for gambling and it's gone up.

  • 1.1% of men are compulsive gamblers and 0.5% of women.

  • This is another male trait.

  • Somehow men are more vulnerable to compulsive

  • gambling than women.

  • But it's only a factor of 2-to-1.

  • But it's an addiction that happens that

  • distorts people's thinking.

  • And it's such an addiction that we have an organization

  • called Gamblers Anonymous that helps people with this.

  • It ruins people's lives.

  • People end up getting a divorce, because you can't

  • stay with someone, married to someone, who is squandering

  • the family money.

  • They do it.

  • They end up sneaking around to gamble, like drinkers sneak

  • around for the next drink.

  • Gambling behavior, it seems to be associated psychologically

  • with a self-image, a sense of who I am and why I'm an

  • important and good person.

  • A sense of competence.

  • Most gamblers do things that they think are revealing of

  • their competence.

  • And they tend to pick a certain form of gambling that

  • they become psychologically identified with.

  • And they avoid any other form of gambling.

  • Gambling behavior is part of what goes on

  • in the stock market.

  • Certain people who have a personality, which makes them

  • particularly interested in gambling, find that a life in

  • finance can give them the kind of stimulation.

  • Gambling behavior, by the way, is almost like a drug

  • addiction in a sense.

  • People who are depressed may go to a gambling casino as a

  • way of getting themselves out of the depression.

  • And they say that when they walk into the casino, suddenly

  • my troubles are gone.

  • I feel invigorated and alive.

  • It's almost like it creates a hormonal difference that they

  • seek, and it's almost like injecting yourself with

  • something, so it's a very hard thing to conquer.

  • I mentioned before, when the New York state in 1811 created

  • the first corporate law that produced a lot of questionable

  • companies, people then said, this is just gambling.

  • It's bad.

  • But the other side of it is that this same gambling

  • behavior, it's not usually a pathology.

  • It's an aspect of human sensation-seeking of various

  • aspects of our psychology that drive us.

  • What the stock market is, in some sense, is a way of

  • channeling this kind of behavior into something

  • productive instead of just a game.

  • And so, they make it very clear in the stock markets of

  • the world, this is about business and this is

  • productive.

  • The same emotional patterns that created gambling behavior

  • as a human universal underlie some --

  • this is not abnormal, it's most people.

  • Underlie traits that work out well.

  • OK, the next major thing I wanted to talk about is

  • overconfidence.

  • And psychologists have found that there's a human tendency

  • to overestimate one's own abilities.

  • We all think --

  • not all of us, most of us think we're above average.

  • Some of us think, we're way above average.

  • And this tendency has been revealed in a number of

  • experiments.

  • I thought I would try one on you.

  • I don't know if it will work.

  • I'll try it on this class, if you will participate in this

  • experiment by a show of hands.

  • I'm going to ask you --

  • I have three questions here.

  • And I want to ask you to write down a

  • 90% confidence interval.

  • Do you have a pencil to write this down?

  • And then afterwards, I'm going to tell you the answer and see

  • if it fell in your confidence interval.

  • OK, so this is what it is.

  • What is a 90% confidence interval?

  • It's a range of values, so that you are 90% sure that the

  • true value lies in this range.

  • So, if I asked you, what is the population of New Haven?

  • You might say, 90% confidence interval that's between 50,000

  • and 150,000.

  • That means, you're 90% sure that the population falls in

  • that range.

  • And so, you should be right 90% of the time.

  • If I ask you to give 90% confidence intervals, you

  • should be right 9 times out of 10.

  • If I ask for a 99% confidence interval, you have to widen

  • the interval so that you should be right 99

  • times out of 100.

  • So, what I'm going to ask you to do, if you will cooperate

  • with me, is give 90% confidence intervals for --

  • I have three questions I'm going to give you.

  • But I have to ask you to be honest, otherwise this thing

  • won't work.

  • You could game me by just giving excessively wide

  • confidence intervals, right?

  • From the ''zero-to-infinity'' type.

  • Then you'll always be right, but

  • you're not playing honestly.

  • So, I have to appeal to your character to do this honestly.

  • So, I have three questions here.

  • I just changed the questions.

  • The first is --

  • now what you have to write down on your notepaper

  • somewhere is your honest estimate of a

  • 90% confidence interval.

  • And so, the first question is, the world population --

  • how many people are alive in the world?

  • As of, I think it was 8:00 a.m.

  • this morning [addition: February 21, 2011].

  • The U.S. Census has something called the World Population

  • Clock and just go --

  • don't cheat.

  • I know, some of you have laptops.

  • Don't do it.

  • But after this you can search Google on World Population

  • Clock and it shows you minute-by-minute how many

  • people there are in the world.

  • Every birth and death.

  • It's not actually recorded, it's a fake.

  • But I mean it's supposed to be an estimate.

  • So, I got the world population.

  • So, what I want you to do, can you write down a lower bound

  • and an upper bound for the world population this morning

  • as measured by the U.S. Census?

  • OK, can you write that down?

  • But I don't want you to make it too wide.

  • Remember, I only want you to be 90% sure.

  • And I don't want you to make it too narrow, because then

  • you're more likely to fail.

  • So, you've written that down, the world population?

  • OK, my next question is --

  • 2.

  • The world, what does it weigh?

  • Well, actually, it's the mass, in kilograms, of the world.

  • Can you write that down?

  • This is astronomy.

  • Let me say, I'm asking for it in kilograms. But you can do

  • it in metric tons.

  • That just knocks off three zeros.

  • A metric ton is 1,000 kilograms. And just so you'll

  • know for sure, that's not the same thing as a long ton,

  • which is U.K. The United Kingdom uses the long ton,

  • which is 2,240 pounds.

  • I just looked this up.

  • And is 1.1 metric ton.

  • And it's not exactly the same as a short ton, which we use

  • in the United States, which is 2,000 pounds, which is 0.98

  • metric tons.

  • Just tell me, how many tons.

  • That's not going to affect your 90%

  • confidence interval, right?

  • Just tell me how many tons does the earth weigh.

  • And then that's the second and I have one more question.

  • How many languages are there in the world?

  • Now, I know you might complain, this is a matter of

  • definition, because sometimes two dialects might be

  • considered a separate language.

  • Well, I'm asking you to give me the number --

  • the World Authority on languages is an organization

  • that has a website called ethnologue.com.

  • And if you go to that website, they're always

  • discovering new languages.

  • They keep track of it.

  • New languages keep getting discovered, because some guy

  • is hiking out in Siberia and they go to this little

  • village, and say, hey, these people are speaking a language

  • that has never been documented before.

  • So, it's this process of learning languages.

  • They also keep dying out, because there's just elderly

  • people in this village, and when they die you know this

  • language is going to die with them.

  • So anyway, the question is, I want your 90% confidence

  • interval for the number of languages, as defined by

  • ethnologue.com.

  • You have to guess how they define a language.

  • But you have an idea more or less what a language is.

  • It's more than a dialect, because they can still

  • understand each other if they speak different dialects.

  • We're talking about really different languages.

  • OK, have you written down three confidence intervals?

  • OK, so I'm going to write down the answers

  • and I hope this works.

  • I'm trusting to your honestly in getting these things,

  • because you good game me and make this not work.

  • But give me your honest count.

  • So, I'm going to write down the correct answer.

  • So, the world population as of 8:00 a.m.

  • this morning [addition: February 21, 2011]

  • was 6,901,330,581.

  • Now, can I get a show of hands, how many peoples'

  • confidence interval includes that number?

  • OK, can someone tell me what percent that is?

  • That is not 90%.

  • You're doing pretty well, though.

  • What do you think, Oliver?

  • STUDENT: About 80.

  • PROFESSOR ROBERT SHILLER: You think it's 80?

  • Let me see them up again.

  • Maybe it is 80, all right.

  • You're doing really well.

  • Some honest people here didn't put their hands up.

  • All right, well, that's one.

  • So, we did 80 instead of 90.

  • What about the weight of the earth?

  • In kilograms. Well, it's 5.974 times 10 to 24th power.

  • And I'll give you that in tons.

  • It's 5,974 billion billion tons.

  • You got that?

  • You might have to do some calculation.

  • It'd be 5.9734 times 10 to the 18th power.

  • [correction: 5,974 times 10 to the 18th power is

  • the weight in tons.]

  • OK, can we do a show of hands?

  • How many people had a number in --

  • how many people are in the confidence interval there.

  • All right, Oliver, what do you think?

  • What's the fraction?

  • STUDENT: 5%, maybe 10.

  • PROFESSOR ROBERT SHILLER: 10%.

  • OK.

  • So this one, we did really well on world population.

  • 80, 10.

  • The last one, how many languages are in the world?

  • Well, according to ethnologue.com there are 6,909

  • languages this morning [addition: February 21, 2011].

  • How many people got that within

  • their confidence interval?

  • OK, what do you think, Oliver?

  • STUDENT: About the same, 10%.

  • PROFESSOR ROBERT SHILLER: 10%, OK.

  • Why did you do so much better on world population?

  • Well, thank you for being honest with me.

  • I think it worked once again.

  • The overconfidence.

  • So, why is it that people are overconfident like this?

  • And psychologists have tried to describe, what it is that

  • goes on in people's minds that produces answers like this.

  • One of them is, that people seem to have a sense that they

  • understand the world more than they really do.

  • It's an illusion.

  • Actually, the world is just infinitely complicated and

  • there are so many surprises.

  • When you think about a question like this, there's

  • many different perspectives that you can take.

  • And if you thought more about it, your imagination might

  • help you to widen your confidence interval.

  • But you can't think of all the perspectives at once.

  • And so, you tend to gravitate to the first one that comes to

  • mind and it gives you an underestimate of the

  • confidence.

  • So, that is overconfidence.

  • By the way, I think it's a little bit higher in males

  • than females.

  • I didn't do a separate male/female count.

  • But females [correction: males]

  • are definitely overconfident.

  • That's the so-called macho personality that's supremely

  • overconfident, which is -- that's not in DSM-IV. I don't

  • think it is, but it is more common among males.

  • But it's really, everyone is overconfident.

  • There's no important sex difference here.

  • Incidentally, I think that overconfidence, and this is an

  • important phenomenon, it goes beyond yourself.

  • It extends to your friends.

  • And you exaggerate --

  • there's a tendency for people to think that I have very

  • smart friends.

  • I was reflecting the other day.

  • When I was an undergraduate at University of Michigan, I was

  • in the honors program and we thought we were pretty smart.

  • And I had a number of young people that I just imagined

  • were heading toward really great careers.

  • There was one student that we called Young Jack Kennedy.

  • You know, this was some years ago.

  • Jack Kennedy was president of the United States.

  • We thought he was a genius.

  • That was probably wrong, too.

  • None of these people are geniuses.

  • I was thinking that most of my friends ended up in very good

  • careers, but nothing that you would think was spectacular.

  • I had one friend as an undergrad, who I thought was a

  • genius, and his name was Bruce Wasserstein.

  • Anyone ever heard of him?

  • Maybe not.

  • Well see, that's it.

  • But he founded his own investment bank called

  • Wasserstein Perella, became really rich and then he bought

  • interest in Lazard Freres, the French investment bank.

  • He was a real big shot on Wall Street.

  • I met him again about 10 years ago and then he died.

  • God.

  • He had a heart attack and died.

  • So, I know his whole life.

  • I saw him when he was 18 and I've watched his whole life,

  • and it's now history.

  • It's kind of scary.

  • But I remember thinking he was a genius as an undergrad.

  • I was wondering, what was wrong with my judgment?

  • Why did I see so many other geniuses?

  • Now that I think back on it, he had a sort of real world

  • common sense that amazed me.

  • He just knew things that -- it wasn't fake knowledge.

  • He seemed to know how things worked.

  • So, I guess I was right about one of them.

  • But not enough that none of you have heard of him right?

  • He has an investment bank named after him.

  • You should have heard of him, but maybe not.

  • But anyway, this thing affects peoples' thinking, too.

  • I think that we tend to think that the head of state who is

  • running, the head of our central bank is a genius.

  • And this really clouds our thinking.

  • It's like our ego extends to the other people that we

  • associate with ourselves.

  • Now, the head of a central bank in another country we

  • have no respect for.

  • It's only in our own country, because it's part of our ego

  • involvement that produces this overconfidence.

  • This tendency for overconfidence produces a lot

  • of anomalies and opportunities for manipulation.

  • So, for example, Rakesh Khurana, who is a professor at

  • the Harvard Business School, has written a book called

  • Search for the Charismatic CEO.

  • He claims that there's a tendency for people to think

  • that CEOs are geniuses.

  • Or at least the one that we found is a genius.

  • And companies then seek out a genius CEO to put in charge of

  • the company as a kind of manipulation

  • of the stock market.

  • They think if we get -- you know, if we got some guy who's

  • run other companies successfully in the past, he

  • must be a genius.

  • Put him in our company, our stock price will go up, then

  • we can sell our executive --

  • we can exercise our options and make a lot of money by

  • putting in this fake genius.

  • And Khurana says, well, there are some people who are maybe

  • geniuses at management, but most of the time

  • they're just lucky.

  • And we tend to develop overconfidence.

  • And then what happens, according to Khurana, is, you

  • put in some guy who turned around some company

  • spectacularly, supposedly.

  • You bring him in to run a new company and he doesn't know

  • anything about this new company.

  • But he has to justify himself, so he lays off a lot of people

  • and shuffles things around, and just destroys everything

  • in the company, and ruins things.

  • This is related to another author that I recommend.

  • I've mentioned him before, I think.

  • Nassim Taleb wrote a book called Fooled by Randomness.

  • He's Lebanese, but now in the U.S. Nassim Taleb, Fooled by

  • Randomness, that says that most of the things that happen

  • in life are just chance.

  • We tend to ascribe them.

  • If they happen to us, we conclude --

  • we're very quick to conclude that it's a

  • sign of our own genius.

  • And if it happens to someone that is a friend of us, then

  • you think, well, I have genius friends, isn't that nice?

  • And so, it leads to mistakes.

  • OK, let me go to another --

  • how much time do I have --

  • cognitive dissonance.

  • This is another psychological principle.

  • The term was coined by sociologist Leon Festinger in

  • the 1950s, I believe.

  • I actually met this guy.

  • That's the nice thing about being in academia, you meet

  • all these great names if you're in long enough,

  • eventually.

  • But what is cognitive dissonance?

  • It's a judgmental bias that people tend to make, because

  • they don't want to admit they're wrong.

  • Maybe I'm oversimplifying this mistake.

  • It's painful to think, that I believe something and it was

  • wrong, so people will cling to old beliefs and try to find

  • evidence that supports their beliefs, because they have an

  • ego involvement with the belief.

  • And so, I will be biased.

  • The famous experiment indicating cognitive

  • dissonance, done by some psychologist, had the

  • following form.

  • They got a list of people who had just bought a car and they

  • knew what make of car.

  • They got the list from car dealers, so they knew exactly

  • what car they had just bought.

  • And they called these people up and asked them to

  • participate in a psych experiment.

  • Or I think they said a marketing experiment.

  • They didn't let them know that they knew what car they had

  • just bought.

  • And then, the experiment was the following.

  • Let's go through a number of -- what magazines do you read?

  • And they said, let's get these out.

  • They got all the magazines that were on the newsstand.

  • And they said, let's look through page by page and tell

  • us which ads you remember reading.

  • What they found is, that people read the ads for the

  • car they just bought.

  • And they avoided especially the car that they thought they

  • might buy, but decided not to buy.

  • So, after you buy a car, you want to confirm

  • your belief in it.

  • So, you selectively get information that

  • confirms your belief.

  • And so, this cognitive dissonance is another factor.

  • It's been demonstrated.

  • It's an error that people make.

  • It doesn't mean that people --

  • again, none of these errors is unviable.

  • People will make the error and then they'll learn from their

  • mistakes and they'll correct.

  • They're not totally cognitive dissonant, but it's just a

  • kind of error that keeps coming up.

  • So, I give you a couple of examples of cognitive

  • dissonance and its effects on finance.

  • So, Will Goetzmann, who is a professor here at the Yale

  • School of Management, and a couple of his co-authors found

  • that mutual fund investors --

  • when a mutual fund does very badly in its investment

  • performance, many or most investors sell the stock and

  • get out of it.

  • But some of them hang on.

  • And they thought that that was due, perhaps, to cognitive

  • dissonance.

  • Because I bought this fund, I don't want to sell

  • because I was right.

  • So, what they did is, they interviewed these people and

  • they found that these people didn't even know how badly the

  • fund has done.

  • They had blocked it out and they had an exaggerated

  • impression.

  • An exaggerated impression of this, which is characteristic

  • of cognitive dissonance.

  • You just forget the evidence that's contrary to your theory

  • and you keep assembling evidence that

  • supports your theory.

  • I have another example of cognitive dissonance and this

  • one was produced by Professor Sendhil Mullainathan at the

  • Harvard Economics Department.

  • And Mullainathan looked at financial advisors --

  • and his co-authors.

  • What they did in this study --

  • that's a whole big profession.

  • I remember at the beginning I pointed out how many hundreds

  • of thousands of financial advisors there are.

  • What they did, it's an interesting experiment.

  • They hired actors to go to financial advisors and ask for

  • their help.

  • And the experiment was the following.

  • They would say the same thing to each financial advisor, but

  • the different actors would present their existing

  • portfolio differently.

  • In other words, you'd go to the advisor and you'd say, I

  • have a portfolio of investments and I'm almost

  • entirely in money market funds.

  • That's all.

  • You'd just say that.

  • You wouldn't express any opinion at all.

  • Another actor would go and say, I've got all of my

  • portfolio in tech stocks.

  • Or I've got all of my portfolio in options.

  • Now, what should advisors tell people?

  • Well, if they were acting really professionally, they

  • should question the assumptions that made the

  • actor supposedly put all their money in one kind of

  • investment.

  • And many of the financial advisors did, but

  • usually they didn't.

  • They didn't question the actor.

  • They assumed that the actor, who had put, supposedly, all

  • of the investments in money market funds, was someone who

  • was very risk averse, or thought that was the right

  • thing to do.

  • And they didn't want to challenge them, so they would

  • walk out of there with maybe a slightly different mix of

  • money market funds.

  • And somebody else who was in a very risky portfolio, they

  • didn't challenge them.

  • And they even sent actors in with almost all of their

  • portfolio in their own company's stock.

  • Now if you work for Ford Motor Company --

  • I noticed my uncle --

  • I had conversations with him about this --

  • who worked for Ford Motor Company and put all of his

  • life savings in Ford Motor Company.

  • I said, Uncle Ralph, you shouldn't do that.

  • Because it's your job and all of your life savings.

  • What if something happened to Ford Motor Company?

  • Fortunately, he didn't work for GM, which

  • became worthless recently.

  • But it can happen.

  • You know, Ford could be completely wiped out.

  • That's your life savings.

  • And you know what he said to me?

  • He said, you know, I've worked at Ford all my life.

  • They treat me well, I believe in them, I'm

  • not going to sell.

  • So, there's lots of people like that.

  • So, when they show up at a financial advisor, the first

  • thing that they should do, the financial advisor should tell

  • them, get out of your Ford stock.

  • That's just too risky.

  • But only 40% of the financial advisors did that.

  • The 60% left them mostly in their own company stock.

  • Why did they do that?

  • Well, Mullainathan thought, it's because the advisors know

  • there's cognitive dissonance, and they're afraid to drive

  • away a new client.

  • Maybe they'll gradually do it over a while, but you just

  • don't challenge their deep beliefs,

  • whatever they say is true.

  • And so, they're kind of yes-men.

  • Not all of them, and maybe they'll come around.

  • It relates then, again, to a moral dilemma.

  • If you are a financial advisor working in private practice,

  • what do you do with people who come to you, if you know from

  • experience that challenging their deep-seated beliefs will

  • drive them away?

  • So, in the real world, this is again --

  • I'm not sure that these financial advisors are doing

  • the wrong thing.

  • If they would eventually tilt them toward a more responsible

  • portfolio, they can't drive them away.

  • I have a lot of -- so many.

  • Let me list some of the others and move on.

  • What else should I talk about?

  • Anchoring.

  • Anchoring refers to a tendency to anchor your opinions on

  • something that captures your attention.

  • The famous anchoring experiment by, it was again,

  • Kahneman and Tversky --

  • I could almost do this experiment here in class with

  • you if I had a wheel of fortune.

  • A wheel of fortune is like on a game show.

  • You spin the wheel and it comes up with a number between

  • zero and a hundred in this particular wheel of fortune.

  • So, this is the experiment.

  • They asked their subjects, how many people --

  • it had to be something that had an answer

  • from zero to a hundred.

  • One of their questions was, how many nations in the world

  • [addition: in percent]

  • belong to the United Nations?

  • So, they asked the question.

  • They said, don't answer me just yet.

  • Think about that question.

  • What percent of nations in the world belong

  • to the United Nations.

  • Then, they spun the wheel, and it came up and it showed a

  • random number.

  • And then, they asked people for the answer.

  • Well, it turns out that people tended to give an answer close

  • to the number that just came up on the wheel.

  • This is totally irrational, right?

  • That wheel has nothing to do with the answer.

  • And yet people were influenced by it.

  • So then, they would follow-up and ask them, hey, that number

  • you gave is the same as the one that just came up on the

  • wheel, or it's close to it.

  • Why did you do that?

  • The guy would say, just coincidence.

  • I wasn't influenced by the wheel.

  • Of course not.

  • But you know they were, because statistically they

  • proved that they were.

  • So, anchoring means that people are attracted to --

  • they're affected by subconscious things.

  • I shouldn't say subconscious.

  • They didn't make a logical connection.

  • When you face real ambiguity and you don't know the answer

  • and you've got to come up with a decision, you are swayed by

  • the most silly and random things.

  • There's a representativeness heuristic.

  • This is also Kahneman and Tversky.

  • And that is, that people overemphasize certain patterns

  • that they think are representative of what they've

  • seen before.

  • So for example, certain patterns in the stock market

  • that may be very rare and unusual.

  • If they remember it, if it somehow attracted their

  • attention, they begin to look for that

  • pattern again and again.

  • And they see it too often.

  • So for example, Head and Shoulders, we

  • talked about that.

  • McGee, the technical analyst, he saw the Head and Shoulders

  • pattern in the stock market.

  • And he saw that it crashed after that.

  • But actually, it's pretty hard to find those,

  • they're kind of rare.

  • And it's not the right way to process data, to be looking

  • for patterns that are representative.

  • And it invites manipulation.

  • So, I'll give you some other bad behavior.

  • If people believe in the Head and Shoulders, if they believe

  • that the Head and Shoulders pattern of stock price

  • movements predicts a decline, here's what I can do.

  • I'll take some thinly traded stock.

  • I'll get a friend.

  • We'll trade back and forth and we'll influence the price to

  • create -- we'll deliberately create a Head

  • and Shoulders pattern.

  • And then we'll short the stock massively, right at the time

  • when the head and shoulders pattern

  • would give a sell signal.

  • We can make tons of money doing that.

  • So, why don't we do that?

  • Well, we don't because it's a manipulation.

  • [SIDE CONVERSATION]

  • PROFESSOR ROBERT SHILLER: I want to then just conclude

  • with social contagion, because it's so important.

  • This is my last --

  • and this is really social psychology.

  • I'm running out of room here.

  • That's social contagion.

  • Social psychology reflects on the fact that people are

  • interdependent, and what I think is affected by what

  • others think.

  • There's something called herd behavior.

  • That's a popular term.

  • It refers to the tendency for people to move with the herd,

  • not consciously.

  • They don't think that they're moving with the herd.

  • I might bring up a little sociology here

  • and I'll use a term.

  • Everything has been psychology, but the great

  • sociologist, one of the founders of the discipline of

  • sociology, was the French scholar Emile Durkheim at the

  • late 19th, early 20th century.

  • And he used the word ''collective consciousness.''

  • And that is, that our opinions about what's happening are

  • formed by a collective understanding of

  • what's going on.

  • We have a tendency to think of ourselves as rational and

  • common sense --

  • all of our views come from common sense

  • processing of facts.

  • I have a sense of belief about what goes on in the world, but

  • I underappreciate the extent to which my views are a little

  • bit arbitrary and shared by millions of other people.

  • You live in a certain point in time in history, and there are

  • certain kinds of facts and ideas and anecdotes that are

  • circulating.

  • There's another term, this is a zeitgeist. That's German,

  • but it's now English.

  • That means "spirit of the times."

  • So, what Durkheim and other sociologists allowed us to

  • understand is, that the zeitgeist is determined by a

  • collective memory, a collective set of facts that

  • we operate on.

  • This herd behavior creates big swings in the stock market and

  • other things.

  • So, it has a huge financial impact.

  • But anyway, I've listed a number of Behavioral Finance

  • principles that really come from psychology, and I've

  • talked about some tests or examples of their proof of

  • their importance in finance.

  • But what do we conclude from this?

  • I think that my conclusion is, that we are evolving toward

  • better and better financial institutions.

  • There is a lot of manipulation and exploitation, but we as a

  • society have outlawed a lot of it.

  • For example, I mentioned doing a stock market manipulation

  • trick to create a Head and Shoulders pattern.

  • That is an offense.

  • It will get you in jail for doing that.

  • And we prosecute that now.

  • So, you can't do that.

  • I'm going to talk more about this in the next lecture about

  • regulation.

  • But it's also people's moral judgments that the people who

  • evolve to become important in finance are people who have an

  • internal compass, a desire for praise-worthiness that

  • eliminates --

  • I'm going to give just two examples of some recent

  • articles about this.

  • In the current issue of the Harvard Business Review that,

  • I assume, is still on newsstands --

  • This is Harvard Business Review.

  • There's an article by Michael Porter and co-author Mark

  • Kramer, Porter is a well-known professor at Harvard, in which

  • he argues that we're coming to realize more and more about a

  • principle called -- he calls it ''shared value.'' Or they

  • call it ''shared value.'' And that is that the manager of a

  • company shouldn't be underestimating the importance

  • of shared value creation with society, with other people.

  • That is, we're all in this together, and if we're mature,

  • we recognize, for example, that I don't want to be

  • exploitative.

  • I don't want to make the local people in my town upset with

  • our company.

  • I don't want our labor force to become disenchanted.

  • Now, what he's saying it's not really about morals exactly.

  • It's more about long-term value.

  • But I guess morals somehow creeps into the same judgment.

  • That mature businesspeople see shared value and that there

  • was maybe not enough emphasis on that.

  • Financial theory was leading us too much toward thinking

  • that a manager should be selfishly pursuing a narrow

  • focus, like maximizing the short-run

  • value of their shares.

  • Anyway, the other example I have, which is also recent,

  • not quite as recent as that, is a book that came out last

  • year by Anna Bernasek, who is actually a

  • journalist, not an academic.

  • But it's called Economics of Integrity.

  • Is that the title exactly?

  • Yes.

  • Economics of Integrity.

  • And her point in that book is, that a sense of personal

  • integrity has dominated what people do in the business

  • world much more than we thought recently.

  • There has been too much disregard of the fact that

  • people do things because they're right.

  • She gives an example in the book -- and I'll close with

  • this concept.

  • She said, let's consider milk.

  • Now, you drink milk regularly, I hope.

  • It's good for you.

  • But it could poison you.

  • People used to get sick from drinking contaminated milk.

  • And you don't ever hear of anyone getting sick.

  • So she said, why is that?

  • Well, we have government regulation of milk production

  • and there are laws about purity of milk.

  • But she looked into it and found that --

  • actually, she didn't think it was mostly the regulation.

  • She thought that you are safe drinking milk because of the

  • integrity of our people, mostly.

  • That if you go out to some milk company and talk to the

  • employees, they might not generally even know about the

  • regulations.

  • But if you ask them, they'll tell you --

  • I mean, are you careful to keep this milk clean?

  • They'll tell you, well, someone's going to drink this,

  • so obviously it's common sense I'll keep it clean.

  • And what she says, it's not primarily the regulation, it's

  • the integrity of the people that makes the economic system

  • work as well as it is.

  • So, anyway, I've emphasized both sides.

  • I've talked about human failings and about people

  • exploiting these failings, about people with antisocial

  • personalities.

  • But we have a system that somehow eliminates this from

  • being the major factor in our markets.

PROFESSOR ROBERT SHILLER: OK, good morning.

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11.行為金融學與心理學的作用。 (11. Behavioral Finance and the Role of Psychology)

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    陳韋達 發佈於 2021 年 01 月 14 日
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