The Economics Of Trust
Tim Harford 09.25.06, 6:00 PM ET
Imagine going to the corner store to buy a carton of milk, only to find that the refrigerator is locked. When you've persuaded the shopkeeper to retrieve the milk, you then end up arguing over whether you're going to hand the money over first, or whether he is going to hand over the milk. Finally you manage to arrange an elaborate simultaneous exchange. A little taste of life in a world without trust--now imagine trying to arrange a mortgage.
Being able to trust people might seem like a pleasant luxury, but economists are starting to believe that it's rather more important than that. Trust is about more than whether you can leave your house unlocked; it is responsible for the difference between the richest countries and the poorest.
"If you take a broad enough definition of trust, then it would explain basically all the difference between the per capita income of the United States and Somalia," ventures Steve Knack, a senior economist at the World Bank who has been studying the economics of trust for over a decade. That suggests that trust is worth $12.4 trillion dollars a year to the U.S., which, in case you are wondering, is 99.5% of this country's income. If you make $40,000 a year, then $200 is down to hard work and $39,800 is down to trust.
How could that be? Trust operates in all sorts of ways, from saving money that would have to be spent on security to improving the functioning of the political system. But above all, trust enables people to do business with each other. Doing business is what creates wealth.
Of course, as Mr. Knack admits, this loads a lot onto a short word. So it's worth trying to get under the surface of trust in rich countries. Economists distinguish between the personal, informal trust that comes from being friendly with your neighbors and the impersonal, institutionalized trust that lets you give your credit card number out over the Internet.
The two types of trust are correlated with each other, because we are more willing to trust people if we feel that, ultimately, we can call the police or get a fair hearing in court.
"The reason why the U.S. is richer than Somalia is mostly not because of culture. The great thing about formal systems, when well designed, is that they make a little bit of public spirit, altruism or professionalism go a long way," says Paul Seabright, an economics professor at the University of Toulouse.
Formal or institutionalized trust sounds cold and unpleasant, but it is just as useful as the personal variety, perhaps more so. Our parents might have enjoyed a line of credit from the friendly owner of the local grocery store. We don't get the same personal service, but we get something much more useful--we can run a line of credit pretty much anywhere, from a hotel in Shanghai to a diner in Memphis to a supermarket in Berlin. Those places don't actually trust us enough to lend us money, but Visa or American Express will, and that will do just as well.
This matters. Adam Smith, the father of modern economics, argued that wealth was built on the division of labor. He gave the famous example of the pin factory in which one worker drew out the pin wire, another cut the wire, a third added the pin head, a fourth sharpened the pin to a point and so on. But the pin factory achieves nothing if the workers can't trust each other, and a modern global economy relies on a division of labor and the accompanying trust that spans the continents many times.
Seabright's book, The Company of Strangers, makes this point with reference to the author's shirt: "The cotton was grown in India, from seeds developed in the United States; the artificial fiber in the thread comes from Portugal and the material in the dyes from at least six other countries; the collar linings come from Brazil, and the machinery for the weaving, cutting and sewing from Germany; the shirt itself was made up in Malaysia." It's just a shirt, and even then it is far too complex a product to be facilitated merely by a network of people who know and trust each other personally.
Yet in a place like Somalia, personal trust is all that is available. It is a war-torn country in the horn of Africa which lacks anything we would recognize as a government, and entrepreneurs have to rely on much more local, primitive and less effective forms of trust. Somalis often rely on clans to settle disputes. That can work well if you're arguing with someone from the same clan, but cross-clan disputes are often messy and unfairly resolved. (Anybody who thought Somalia's poverty had to do with a lack of natural resources might take a look at resource-rich Nigeria, a country which is nearly as poor, and then at resource-poor Singapore, one of the richest countries in the world.)
That is a reminder that institutionalized trust might be even better than the touchy-feely type, which simply isn't available to everyone. Personal trust can be benign, but it can also be embodied by the old-school-tie network, political patronage or a criminal mafia.
"Factors which increase trust in society are not necessarily a good thing, because they can increase the bonds between gang members, whose main economic success comes from extorting or coercing other people," explains Seabright.
Trust can also be denied to ethnic minorities: the credit card companies may not be entirely blind to race, sex, color and creed, but I am willing to bet they are much closer than the local bank manager in the 1950s.
Economists Kerwin Charles and Patrick Kline have tried to put their fingers on the arbitrariness of personalized trust by looking at car pooling and race. They argue that car pooling is a good measure of trust: can you trust your fellow travelers not to be late, drive badly or murder you and leave your body in a ditch?
Charles and Kline predict that, for example, African-Americans will find it easier to car pool if they live in an area with lots of other African-Americans. The statistics seem to bear them out. Trust matters, and if you live in an area full of people who look like you, you will enjoy more of it. Perhaps the institutionalized version of trust is not so bad after all.
Meanwhile, experimental research by economists Ed Glaeser, David Laibson and Bruce Sacerdote shows that the way people trust each other simply isn't fair. The researchers organized a "trust game." Two students met ahead of time to size each other up socially, then they played the game. The first student could give up to fifteen dollars to the second student; the experimenters doubled the gift, and then the second student had to decide how much to give back. The game is a measure of trust because the first player has the power to double the size of the pie, but only at the risk of getting nothing back from the second player. What was striking is how much social factors such as race and status encouraged the second player to be trustworthy.
"If the first player has a sexual partner, the second player will send back 17% more than they otherwise would have done," observes David Laibson, a professor at Harvard. Since the second player doesn't know about the existence of a boyfriend or girlfriend, Professor Laibson thinks that it's a proxy for charm, status and social capacity.
The second student will also send more money if the first student drinks more beer--suggesting sociability--or if he or she is of the same race. Pure status matters too. Students who have fathers with a college degree, or who don't have to work to fund their studies, receive significantly more money.
"And America is supposed to be a classless society," comments Professor Laibson. Trust matters, but if you really want to bask in its effects, make sure you start at the top of the heap.
Tim Harford, a columnist for the Financial Times, is author of The Undercover Economist.
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