Ulterior Motives

Health and insurance and politics and behavior

Art Markman, Ph.D. — Thu, 19 Nov 2009 18:10:50 +0000

This post will make you uncomfortable. You should read it anyway.

I'm going to talk about health behaviors and dangerous diseases. And we don't like to think about disease and death, and so we avoid it.

Instead, we talk around disease and death. For example, right now, there is a real uproar over the recommendation that women should not start having regular mammograms until they turn 50. Opponents of health-care reform have taken this recommendation as the first shot in the war to ration health-care to Americans.

How is this talking around disease and death? It is easy to express outrage that the government might take steps to limit our access to health care. What is hard is for each of us to recognize that there are lots of behaviors we could engage in every day that would have significant benefits on our long-term health and would cost little or nothing to perform. That is, we would prefer to shift the blame for our future illnesses to someone else-anyone else-rather than take on that responsibility ourselves.

I'll give two examples in this post.

The first is breast self-examination (BSE). BSE is a technique that women can learn to perform that takes about 10 minutes a month that looks for lumps and abnormalities in the breast. Population-wide, studies suggest that BSE is not actually that effective for detecting cancers. However, the American Society of Breast Surgeons has data that indicate that BSE is as effective as mammograms for women who have a high risk for breast cancer (because they have a family history of breast cancer). Yet a wide range of studies suggest that the compliance rate with BSE is about 10-20%. That is, only about 10-20% of women actually perform BSE.

Why?

Well, nothing will ruin your day faster than finding something that might signal that you have a serious illness. Just like you might be prone to avoid reading this post because the material is uncomfortable, you are likely to avoid doing a self-diagnostic test because it might tell you something you don't want to hear. So, here is a test that is free. No government will stop you from doing it. Yet, women are highly unlikely to perform it.

Now, let's try another one. Obesity is a huge problem in the United States. (Sorry, couldn't resist the pun.) Most Americans are carrying more weight than they should. And this extra weight has been associated with a variety of health problems.

The formula for maintaining your weight is simple. If the number of calories you take in equals the number of calories that you burn in a day, then your weight doesn't change. So, if you want to lose weight, for example, you need to either decrease the number of calories you take in, or increase the number of calories you burn.

Easier said than done, of course. And I'm not about to answer the question of how to diet effectively here.

But think about your average day. How often do you look for the parking space closest to the store you are about to go into? How often do you take the elevator up one flight rather than walking up the stairs? How often do you hop in the car to go get lunch rather than walking a few blocks?

For each additional mile that you walk in a day, you burn about 100 calories. For most of us, getting an extra mile of walking wouldn't be that hard with just a few simple changes in our routine. For example, park your car at the edge of a parking lot and walk rather than parking close to the store.

But, in the moment, we are thinking about minimizing the time we spend on errands. We don't factor in the health benefits of an extra hundred yards of walking. That would require thinking about our health. And we don't really like thinking about health.

So what's the point here?

On the road to health-care reform, we must ensure that we maximize the number of Americans who get health insurance. At the same time, we must ensure that this increase in coverage does not compromise the standards of care that we have come to expect. At the same time, though, we cannot shirk our responsibility for our own health by resting it solely on the shoulders of the medical system. There are lots of things we can do to maximize our own health. These activities have almost no cost.

But they do require that we be willing to think about health and sickness in order to do them.

You again! The role of significant others in our social interactions

Art Markman, Ph.D. — Tue, 17 Nov 2009 16:56:42 +0000

Some patterns in our lives tend to repeat. You may meet a new person, and suddenly find that you talk as though you were back in college with them. Or, you may meet a new romantic interest, and you speak to them as if they were an old significant other. Or you my have a boss and you find yourself talking to him as if he was your father.

What is going on?

It is hard to have to treat each new person in your life fresh. After all, there must be some value to all of the experience you have had with other people you have met.

Research by Susan Andersen, Serena Chen, and their colleagues suggests that we do use our experience with important people in our lives to help us figure out how to act with new people that we meet.

The basic idea is simple. If you meet a new person, and he has some of the characteristics of your father, then you will engage in behaviors with that person that are similar to the kinds of interactions you have had with your father. You will also assume (unconsciously) that this person will have other characteristics that your father has. So, your interactions with this new person are being shaped unwittingly by your own relationship with your father.

This use of your knowledge of significant others in social settings is a double-edged sword. On the positive side, recycling your social knowledge allows you to decide quickly how to interact with new people. Furthermore, when a person reminds you of a significant other from your past, it allows you to develop a close relationship with him or her fairly quickly.

On the negative side, you are reminded of these significant others unconsciously. You are not deliberately saying, "This man reminds me of my father, so I am going to treat him that way." It happens without your awareness. That can lead to a few potential problems.

First, not every relationship with a significant other from our lives is a healthy and positive relationship. If you had an uncomfortable relationship with a parent, then you may find yourself having uncomfortable dealings with new people who remind you of that parent. You may experience this discomfort without knowing why you feel negatively toward that person.

Second, while a new person in your life may remind you of someone from your past, that person is still unique. The research by Andersen and Chen suggests that once you make a link between some new person and a significant other from your past, you begin to assume that this new person shares other characteristics with this significant other. As a result, you may fail to pick up on subtle differences between this new person and people from your past.

If you find yourself in a new relationship with someone (whether it is a friendship, a work relationship or a romantic relationship) and you find that you are starting to repeat old patterns of behavior, then ask yourself whether there is someone from your life that is like this person. If you do a little digging, you may discover that you are actually treating this new person as if they were someone else. Once you know why you are treating a new person using old patterns of behavior, you can try to be more aware and mindful of creating unique patterns of interaction

The difficulties of haggling

Art Markman, Ph.D. — Wed, 11 Nov 2009 14:59:11 +0000

In the first week of November, I was an invited speaker at the Cognition Emotion and Motivation conference that is in Tunisia every two years. Most of the attendees at the meeting were from Tunisia or from other French speaking countries. So, the conference was a great way to catch up on research being done that is not typically published in the Psychology journals published in English. I will have more to say about that in a future post.

But, first, a few words on haggling and why it is so difficult to do well.

Because I had never been in Tunisia before, I wanted to bring home some souvenirs for the family. And that required walking through the market. I walked into one shop that had some nice jewelry and picked out a pair of inexpensive earrings. I know they are inexpensive, because I have seen similar ones in shops in the US. You can usually get them in the US for between $5 and $7. The shopkeeper made a big show of treating me like a valued friend and then suggested that these earrings could be had for the special price of 152 dinar (about $120). Now, I was prepared for having to haggle a bit over the price, but I do think my jaw hit the floor at a markup of 24 times the expected price. Eventually, we settled on something more reasonable (like 7 dinar), but that required an extended discussion, repeated threats to walk to the shop next door, and more than a little stress.

This small encounter, though represented a lot of what makes it difficult for people to negotiate in many situations in life. I'll focus on two here.

The first is a process called anchoring and adjustment. Sometimes we know the value of something, because we have seen it before. For example, having seen earrings like the ones in the stall, I was pretty confident I knew their value. Often, though, we are not entirely certain. We have a vague idea, but we need some guidance from the world. For example, when people are on the game show The Price is Right, they make guesses about the value of a product on display. The first person makes a bid. The second person, can then use the first person's bid as an anchor. They might think that the actual price is really higher than that anchor, and so they will adjust it a bit to get into the neighborhood of the actual price.

A lot of research suggests that people perform this kind of anchoring and adjustment, but they end not to adjust enough. So, when the shopkeeper says that the price of the earrings is 152 dinar, that is clearly too high, and you will adjust that price downward. But unless you know the real value of the earrings, you are unlikely to adjust enough. So, you might end up at 20 dinar or 40. You'll still feel like you are getting a bargain, because the anchor was set so high.

The second factor is the social situation. The shopkeeper does not set up an antagonistic situation. He is your friend. He invites you in. He calls you friend. He speaks conspiratorially about the other shopkeepers who are dishonest.

Now, of course, you have a relationship with this person. And most of us want to please others. When the shopkeeper acts offended at our counter offer, we feel as though we have done something wrong. Of course it is an act on his part. But he is more skilled at these interactions, having hundreds of them every week. For us, we have to overcome our natural tendency to be cooperative in conversation in order to haggle effectively.

What is amazing is how powerful just these two elements of behavior can be. When standing with a shopkeeper you have never met before and will never meet again, it is still difficult to hold your ground, to threaten to leave the shop or even to actually leave.

So what can you do to haggle (or negotiate) more effectively?

First, enter any negotiation with your own sense of the value of what you are negotiating over. Do not let someone else provide the starting anchor point for establishing value. If you are going to negotiate over something like a car, check the web to find out the value of the car before going. If you find yourself in Tunisia in the market, make a guess at the value of the item before the shopkeeper says anything. Anchor your judgment on your guess rather than the shopkeeper's offer.

Second, think about your own social behavior. If you are the kind of person who is cooperative in conversation and who does not like to feel as though you have insulted others, find a negotiation partner. Bring along someone else who will drag you out of the store or shop before you spend too much. That is, fight social pressure of one kind with social pressure of another.

And if you do find yourself in the market in Tunisia and you do end up paying too much, at least you will have a good story to tell about it in the end.

Your actions affect what others do. Even when those others are infants.

Art Markman, Ph.D. — Fri, 30 Oct 2009 14:07:15 +0000

Western culture tends to focus on the individual and on individual rights. We assume that people have the right to do what they would like, at least as long as those actions don't interfere with others. But, what does it mean for one person's actions to affect the actions of another?

Research by Henk Aarts, Peter Gollwitzer, and Ran Hassin described in a 2004 paper in the Journal of Personality and Social Psychology suggests that just watching or reading someone striving toward a goal can make you more likely to adopt that goal as well. In one study, for example, participants who read a story about someone who was trying to make money were more likely to look for opportunities to make money and to put effort into them than people who read a story that was not related to making money.

An interesting study with young children suggests that children as young as 18-months-old are also affected by the actions they see. Research with children of this age suggests that they do like to be helpful. For example, Felix Warneken and Michael Tomasello described studies in a 2006 paper in Science in which 18-month-olds will help adults to reach things that they have dropped.

These studies were extended by Harriet Over and Malinda Carpenter in a study published in the October, 2009 issue of Psychological Science. They showed 18-month-olds a series of pictures. For some infants, the pictures showed people standing close together looking at each other. Three other groups were run as well. Some infants saw pictures with only one person in them. Others saw pictures with two people, but they were not looking at each other. A third group saw pictures with figures that were not people.

After viewing the pictures, a different experimenter (who did not know what pictures the infants had seen) asked the child to play a game. The experimenter was carrying pick-up sticks to a table and accidentally dropped them. The experimenter looked at the infant and at the sticks. In the first 10 seconds after dropping the sticks, about 60% of the infants who saw pictures of people standing together helped the experimenter by picking up the sticks. Only 20% of the infants in each of the other conditions helped right away.

This finding suggests that infants who see others being social are encouraged to be social themselves.

It is important to realize that both in the studies with adults and with infants, that the people in the study are unaware that observing others has affected their own actions. In the studies with adults, participants are asked specifically about the relationship between reading stories about people and other aspects of the study, and they did not realize there was a connection. The infants in the study by Over and Carpenter are not asked, obviously, but it seems unlikely that they are aware that seeing a set of pictures would make them help an adult.

Taking all of this work together, it seems that the borders of our actions are broader than we might think. People are affected by what we do if they just see or hear about our actions. We serve as an example to others in what we do. And this example is one that influences the behavior of others, even though they are not aware of the effect that our actions have had on them.

Categories, essentialism, race, and culture.

Art Markman, Ph.D. — Tue, 27 Oct 2009 13:45:14 +0000

Placing something in a category and describing its properties have very different effects on the way we think about things. In my last post, I pointed out that calling someone a musician makes playing music seem much more central to their being-more essential-than just saying that they play music. What about categorizing people by their race?

Throughout the world, racial, cultural, and ethnic differences are used to place people into different categories. Once we categorize people in this way, we automatically assume that they have the essence of this category. For example, in 1994, Richard Herrnstein and Charles Murray wrote a book called The Bell Curve in which they documented racial differences in IQ test scores. An implicit assumption of this book was that it was meaningful to classify people by race and that these racial categories reflected something essential about the people who were categorized.

How do racial categories develop? This issue was addressed in a paper by Marjorie Rhodes and Susan Gelman in a 2009 paper in Cognitive Psychology. They looked at two factors: age and cultural background. The participants in their study were primarily White. They came either from a mid-sized city that was politically liberal or from a rural area that was politically conservative. The participants ranged in age from 5-18.

The younger children played a game with a puppet. They were told that the puppet came from another place where they do some things wrong, but they do other things differently from the way we do them, but they are not wrong. After some practice with the game, children were shown an object or person and then were shown a second object or person and were told that the puppet thinks they are the same kind of thing and were asked whether they were right. For example, they might be shown a wolf and a lion and were told that the puppet thought that they were the same kind of thing. Over the course of the study, the puppet classified animals, and artifacts (like cars, forks, and dresses). The puppet also classified people based on gender and race.

The older kids did a similar task, but without the puppet. The oldest kids in this task (who were about 17) were asked these questions in a pencil-and-paper test.

So, what happened?

For simplicity, I'll just focus on the animal and racial categories. For the animals, kids of all ages tended to say that the puppet was wrong when it put together animals of different categories. That is, starting at age 5 and upward to age 17, children felt that it was not correct to put different animals in the same category.

The data for race were much more complex.

As an example, the participant might see a White girl and then an Asian girl and be told that the puppet thought that they were both the same kind of person.

The youngest children (5- and 7-year-olds) showed no strong preference for saying that the puppet was right or wrong when putting together people of different races. About half the time they said the puppet was right and half the time they said the puppet was wrong.

For the older children (10-year-olds and 17-year-olds), their answer depended on where they grew up. The older children who grew up in the politically liberal area said that it was correct to classify people from different races. Those who grew up in the politically conservative area said that it was incorrect to classify people from different races. That is, older kids from liberal environments had no problem with a category that involved people from different races, while older kids from a conservative environment thought it was wrong to classify people from different races in the same category.

The first thing to notice about these data is that the belief that race is a possible basis for classifying people emerges late. This observation is similar to what anthropologist Lawrence Hirschfeld has observed in his research.

The second thing to see is that beliefs about whether it is necessary to classify people based on their race depend on what other members of your culture suggest. You are much more likely to think it is necessary to classify people based on race if you grow up in a politically conservative environment than if you grow up in a politically liberal environment.

The reason that this type of classification matters is that classifying people into a group brings along the belief that the members of that group share some essential characteristics. Consistent with that, Rhodes and Gelman asked the 17-year-olds to fill out scales about how strongly they believe that members of the same race share deep underlying characteristics not shared by other races. Those kids who were most likely to think that it was necessary to classify people based on race were also the ones most likely to think that racial categories reflect something deeply similar about the members of that race.

For each of us, I think, it is worth reflecting on how likely we are to treat people differently because of the way we categorize them.

Categories, Essences, and Behavior Change

Art Markman, Ph.D. — Fri, 23 Oct 2009 16:03:28 +0000

When we talk about things, we have to give them labels. Those labels end up having a big influence on the way that we think.. When we say that someone has depression, that seems to say more about them than just that they are sad, or have trouble sleeping, or has difficulty getting excited about positive events. The label suggests that there is something deep about that person that causes these symptoms. And in the case of depression, of course, it is true that having depression tends to cause all of these symptoms.

Douglas Medin and Andrew Ortony wrote a chapter in the 1989 book Similarity and Analogical Reasoning in which they called this effect of labels psychological essentialism. That is, when we describe something with a label, we are saying that the object is part of a particular category. For example, if we say that Susan has depression, we are saying that she is part of the category of people who are depressed.

A consequence of placing someone in a category is that we now think that there is some set of characteristics that are shared by everyone in that category. That is, we believe that the category has an essence. It is not important whether that particular category really has an essence. If we place an object in a category, people treat the object as if it has the essence of that category. Psychologically, then, a person suffering from the symptoms of depression is different than a person who is depressed, because we believe that the person who is depressed has some essence that the person who is just suffering from the symptoms does not.

Susan Gelman and Gail Heyman documented this effect in a 1999 study in the journal Psychological Science with children. They found that when you described someone as a carrot-eater, children thought that eating carrots was a deep part of who that person was. When you describe someone as a person who eats carrots, then they thought that eating carrots was less a crucial part of who they are.

I have always thought that you can use this effect as an insult as well. For example, someone might ask, "Is John a painter?" Dismissively, you could say, "Well, he paints..."

Psychological essentialism may be important for behavior change.

We use labels to describe things all the time. Often, we use these labels just to describe something in order to communicate it to someone else. The work on psychological essentialism suggests that after we use a label, we will treat the characteristics we label as less easy to change than characteristics we have not labeled. It seems easier to change the symptoms of depression than to change someone who is depressed. If we say that someone is aggressive, then it seems harder to expect them to change their behavior than if we just think that they have acted aggressively.

Behavior change seems much more difficult to achieve when we label a person as having that behavior rather than just describing their behaviors. So, when we want to change our behavior, we should consider describing ourselves as someone who has a particular behavior rather than labeling ourselves as someone for whom that behavior is a characteristic. We need not think that any of our behaviors truly describes our essence.

Trauma and the benefits of writing about it

Art Markman, Ph.D. — Tue, 20 Oct 2009 13:53:58 +0000

Psychological trauma is bad for your health. The stress of abuse, violence, or the unexpected death of a loved one can cause all sorts of health problems. People suffering after these events may stop working effectively in school or at their jobs. They may lash out at friends, family, and coworkers. They may experience significant illnesses as stress depresses their immune systems.

Why does psychological trauma have these long-lasting effects.?

One reason for the stress of psychological trauma is that our representations of these traumatic events are fragmented. Psychologically traumatic events are ones that have no good explanation. The sudden death of a loved one may seem senseless. Abuse you suffer is a betrayal of a sacred trust. You have painful facts with no story to bind them together.

Because these memories and events are painful, our natural tendency is to avoid thinking about them. We suppress thoughts about these negative events and hope they will go away. But, they don't.

The mind is most settled when there is coherence to our thoughts. We seek to resolve conflicting thoughts by remembering them and processing them. So, a dangerous cycle can develop with traumatic events. Because they are fragmented, there are constant reminders of them. But, because they are painful, we do not process them deeply. And so, we suffer the stress of remembering a painful situation without resolving the incoherence.

Research by my colleague Jamie Pennebaker and his colleagues suggests that one of the best therapies for this kind of psychological trauma is also one of the simplest: writing. He describes this procedure in a 1997 paper in Psychological Science. People are asked to spend three consecutive days writing about one or more traumatic events. They are encouraged to really explore the thoughts and emotions surrounding the event, and to tie it to relationships with significant others. In studies of this technique, people doing this writing are compared to others who write about unemotional topics like time management.

As you might expect, writing about these emotional events was very difficult for people. They did not enjoy the experience, and they found it painful. However, the long-term effects of this writing were fascinating. If you followed the people in these studies over time, they reported fewer illnesses, they went to the doctor less often, and they suffered fewer symptoms of depression in the future. They were less likely to miss work and school, and their performance at work went up. These effects lasted for months and years after writing.

What is particularly interesting about this procedure is that it is just an effect of writing about these events. The people doing the writing do not have to believe that anyone will ever read what they wrote. So, the benefit of writing is not in disclosing this personal information to someone else. The benefit is in creating a story that links together the emotional memories. Making these traumatic events more coherent makes memories of these events less likely to be repeatedly called to mind, and so they can be laid to rest.

Unrealistic optimism about problem drinking is dangerous.

Art Markman, Ph.D. — Fri, 16 Oct 2009 16:00:06 +0000

An important part of everyone's self-concept is a sense of how we compare to others in our behaviors. A common observation is that many people are overly optimistic in their judgments about themselves relative to others. For example, on average, people think they are more likely to be successful in business than others, or to be less likely to suffer from serious illnesses than others. Not everyone can be more successful in business than others, of course, so somebody in that sample must be being too optimistic.

What is the effect of this optimism on behavior?

It is likely that being overly optimistic can have many different effects on behavior depending on the kind of behavior. In this post, I want to focus on the influence of optimism on drinking. Amanda Dillard, Amanda Midboe, and William Klein reported an interesting study in the November, 2009 issue of Personality and Social Psychology Bulletin in which they followed a group of college students for one and a half years.

Students were asked about whether they thought they were more or less likely to be at risk for drinking problems than their peers. They were also asked about a number of problem drinking behaviors they might have experienced during that semester (including getting sick, blacking out, and missing class. They were also asked about the amount they typically drank. In three follow-up questionnaires given every six months, they were asked additional questions about their drinking behavior.

The first question is whether there were people who were unrealistically optimistic? The answer to that question was clearly yes. There was a group of people who felt that they were at low risk for drinking problems, yet those people did drink more than their peers. These people were unrealistically optimistic. Not everyone was unrealistically optimistic. There was another group of realists who either did not drink much and correctly felt that they were at low risk for drinking problems or drank substantially but believed they were at risk for drinking problems.

The study then compared the realists to the unrealistic optimists. The unrealistic optimists were more likely to experience negative events as a result of drinking than the realists in all of the followup periods. Six months after their initial assessment, the unrealistic optimists experienced 20% more negative episodes than the realists, and by the following year, they were experiencing 54% more negative episodes.

There are many reasons why the unrealistic optimists experience so many more alcohol problems than their peers who are realistic about their drinking. For example, the unrealistic optimists may pay less attention to the consequences of their drinking than the realists in order to maintain their self-concept that they are not problem drinkers. In addition, the unrealistic optimists may not be as good as the realists at recognizing the potential dangers of drinking.

So, if unrealistic optimism can lead to bad behaviors and bad consequences, why are some people unrealistically optimistic? One reason is that this optimism may make people feel better in the short-run. Those people who are unrealistically optimistic are not likely to be worried that their drinking behavior poses a long-term problem, and so they will experience little anxiety about their drinking. People who are realistic about drinking may have more anxiety about drinking.

In the end, though, at least for behaviors that can have negative consequences like smoking, risky sex, or excessive drinking, it is probably best to be realistic about the dangers of these behaviors.

Thinking about weighty matters: Weight while thinking matters.

Art Markman, Ph.D. — Tue, 13 Oct 2009 12:48:05 +0000

Starting in the 1990s, mainstream research in Psychology began to take seriously the relationship between mind and body. This research has sometimes led to some strange discoveries. Here's one.

Our language is full of metaphors that relate abstract concepts to specific bodily states. One common metaphor relates weight and heaviness to importance. For example, when you do a little light reading, the book is not that important. When we talk about people who think deep thoughts, we consider them to have intellectual heft.

These metaphors might signal something important about the relationship between mind and body, but the might just be a convenient way that language uses to express the abstract concept of the importance of thoughts. After all, a few weeks ago, I wrote about how language uses the metaphor that anger is a heated fluid in a container ("John was boiling mad."), but that metaphor does not seem to be a good description of how anger really works.

A paper by Nils Jostmann, Daniel Lakens, and Thomas Schubert in the September, 2009 issue of Psychological Science put this idea to the test in a series of clever studies. I'll describe two of them here.

In the first, they had European participants rate the value of small amounts of money from a number of foreign currencies (like the Japanese yen). People made their ratings by marking a scale with a pencil. The rating scales were on a sheet of paper attached to a clipboard. The clipboard was either relatively light or relatively heavy. The people who were carrying the heavy clipboard rated the money as more valuable than the people who were carrying the light clipboard.

If weight were really making things seem more important, then that ought to have an influence on the way people think about issues. In a second study, the experimenters had people evaluate two somewhat related statements. First, they read a brief description of the mayor of their town (Amsterdam) and rated the mayor on a number of attributes like trustworthiness and likeability. Then, they rated how much they liked living in the city. As before, they performed this study either while carrying a light clipboard or a heavy one.

For the people carrying the heavy clipboard, the ratings about the mayor and the ratings about liking to live in the city were highly correlated. That is, people who liked the mayor said they liked living in the city. Those who did not like the mayor said they did not like living in the city. On the other hand, for those people carrying the light clipboard, the ratings about the mayor were not at all related to the ratings about living in the city. This result suggests that carrying the heavy clipboard made people think more about their ratings and led them to put a premium on being consistent from one rating to the next.

These findings suggest that experiencing weight and heaviness is enough to trigger the concept of importance. This idea of importance then affects people's judgments of value and leads people to seek consistency in their thoughts.

Heavy.

More information makes you more confident, if not more accurate

Art Markman, Ph.D. — Fri, 09 Oct 2009 14:43:31 +0000

Confidence matters. We are much more likely to act in situations when we are confident. We make purchases based on confidence. We are also persuaded by others based on their confidence. A statement made confidently and forcefully is much more likely to sway our opinion than a statement that is hedged.

Presumably, the power of confidence lies in the belief that when people are more confident in an outcome they are more likely to be correct in their predictions.

There have been many studies over the years that demonstrate that people tend to be overconfident in their judgments about how likely they are to be correct about a prediction or an answer to a question. But what causes this overconfidence?

A 2008 paper by Claire Tsai, Joshua Klayman, and Reid Hastie in Organizational Behavior and Human Decision Processes suggests one factor that makes people overconfident. They find that as people get more information about a judgment they are making, it increases their confidence, even if it does not increase the accuracy of their judgment.

In one study in this paper, they found experts in college football and asked them to predict the outcomes of a number of games. The names of the schools playing the games were not given. Instead, people were given information about how the teams had performed to that point in the season on a variety of aspects of performance that are useful for predicting the outcome of a game (like the average number of yards that the teams had gained in their games so far that season).

For each game, the participants were initially given six measures of performance for each team and were asked to predict which team would win the game and the point spread between the teams. They were also asked to rate their confidence in their judgment. Based on this initial information, people predicted the outcome of the game correctly about 63% of the time, and their average confidence was about 68%. That is, they were overconfident, but not very overconfident.

Then, people were given 6 more measures of performance and they repeated the judgment, again predicting the outcome of the game and the point spread, and giving their confidence. This was repeated 3 more times, so that people ultimately made 5 judgments and saw 30 measures of performance for each game.

As people got more information, their overall accuracy did not change much. After seeing all 30 cues, people were only correct in predicting the winners of the game 67% of the time. However, by the end of the study, they were 79% confident in their responses. That is, their confidence went way up as they got more information, even though their accuracy stayed the same.

One thing that seems to happen as people get more information is that they start to go from specific information to more general evaluations of aspects of team performance. So, based on a few different measures of performance, a judge might now make an evaluation of the effectiveness of a team's run defense or passing attack.

Of course, all information is ambiguous. Not every measure of performance tells the same story about teams. As you get more information, though, you become more free to pick and choose the information that is consistent with the story you are trying to tell. In this way, you find information that helps you to confirm what you already believe to be true. This tendency to seek information that supports a conclusion you have already drawn is called confirmation bias. This confirmation bias will increase confidence in the judgment you have made.

It is important to realize that confidence and accuracy are not that highly related. We are often asked to make decisions on the basis of expert opinion. There is a temptation to rely on the confidence of the expert to decide how much of that expert's opinion we should trust. Perhaps we are better off looking at that expert's past performance to make up our own mind about how confident we should be in the accuracy of their judgments.