Why has there been a foreclosure crisis in the United States? Two popular explanations are that 1) evil mortgage brokers forced people to take mortgages they could not possibly honor, and 2) those taking the mortgages did not understand what they were doing. As an economist who insists on logic and rationality, it is difficult to adopt these points of view, except that a point could be made about perverse incentives in the mortgage industry where the risk is masked and pushed unto unsuspecting people. But were mortgage holders really that stupid to think they would be able to make it? After all, I know several PhD economists who are still underwater, and they do not look stupid to me.
Christopher Foote, Kristopher Gerardi and Paul Willen come to the rescue. They argue that market participants made perfectly rational decisions given the information they had a the time, and in particular given the beliefs they had. The latter turned out to be too optimistic in retrospect though. Foote, Gerardi and Willen come to this conclusion with an interesting data analysis. They draw 12 "facts" that together contradict the popular explanations. Foremost, it does not appear that there is any correlation between exploding mortgage rates and mounting foreclosures. Also, even borrowers with spotty credit have had a remarkably good repayment history. One should thus not conclude that mortgages were designed to fail. Furthermore, all the instruments and innovations in the mortgage industry were introduced well before the past decade, and there was no significant regulatory change. Market participants knew what they were doing, had plenty of information and understood the risks. They were too optimistic though. Finally, no top-rated mortgage-backed security turned out to be toxic. The same cannot be said about similar bond-based securities.
All in all, there was nothing really wrong with the mortgage market apart from being too optimistic. In other words, there was a bubble, which can be a perfectly rational outcome. So there. But we still need to better cope with the eventuality of a bubble.
Showing posts with label rationality. Show all posts
Showing posts with label rationality. Show all posts
Is pardoning prisoners the best way to keep jail costs low?
I mentioned yesterday that we do not know whether capital punishment is a deterrent or not. What about imprisonment sentences? That is much harder to establish without very precise coding of convictions in multiple jurisdictions with different sentences for the same crime. Finding or establishing such a dataset should be very difficult. But maybe we can find some partial answers in indirect ways.
Nadia Campaniello, Theodoros Diasakos and Giovanni Mastrobuoni use an interesting natural experiment in Italy. There, the parliament occasionally decides on mass pardons to reduce jail crowding. When such proposals are being discussed, suicide rates in Italian prisons drop. That means clearly that prisoners do not like ex-post being in prison, and sufficiently to make life depend on it. If this matters also ex-ante (before they head to jail and in particular before the decide to commit a crime), we should see a deterrence effect. But this may be a big if.
Nadia Campaniello, Theodoros Diasakos and Giovanni Mastrobuoni use an interesting natural experiment in Italy. There, the parliament occasionally decides on mass pardons to reduce jail crowding. When such proposals are being discussed, suicide rates in Italian prisons drop. That means clearly that prisoners do not like ex-post being in prison, and sufficiently to make life depend on it. If this matters also ex-ante (before they head to jail and in particular before the decide to commit a crime), we should see a deterrence effect. But this may be a big if.
The housing bubble: fooled by efficiency
In retrospect, the large rise in housing prices before 2007 looks suspect, many would even call this a bubble. But when you observe it in real time, it is much more difficult to judge whether house price inflation is excessive, although economists have been calling for it. A characteristic of many bubbles is that expect prices to increases forever, while it clearly cannot be true, at least in this magnitude. So somehow people are fooled.
Brian Peterson rationalizes this in a search model where the search frictions allow prices to deviate from their fundamental. The innovation of this model is that people are assumed to believe that price are not affected by the search frictions: they think markets are fully efficient.This means that instead of bargaining over the house price level, buyers and sellers bargain over house price increases. One interesting consequence of this is that turn-over volume and price inflation are then positively correlated. And once you quantify the model, about 70% of he price run-up can be explained by this "foolish" behavior.
Brian Peterson rationalizes this in a search model where the search frictions allow prices to deviate from their fundamental. The innovation of this model is that people are assumed to believe that price are not affected by the search frictions: they think markets are fully efficient.This means that instead of bargaining over the house price level, buyers and sellers bargain over house price increases. One interesting consequence of this is that turn-over volume and price inflation are then positively correlated. And once you quantify the model, about 70% of he price run-up can be explained by this "foolish" behavior.
Economists' political bias and model choice
One can count on Gilles Saint-Paul for innovative research topics. During his career, he has addressed and impressive array of topics that range far beyond Economics strictu sensu. For this reason, I have reported several times about his latest research.
His latest opus is an introspection in our profession and how our political biases influence our modelling choices. He claims that an economist with conservative inclinations will favor a model with smaller fiscal multipliers. While the ethical thing to do would be to be driven by empirical evidence, this may just be a subconscious choice. But at least economists strive to be logically consistent, and if one choose a large multiplier, then then must also claim that demand shocks are substantial, as models with large multipliers rely on this. Looking at evidence from the Survey of Professional Forecasters, Saint-Paul finds that forecasters who believe that expansions are more inflationary also adhere to the belief that public expenses are less expansionary.
Saint-Paul goes further, though. His claim is that we live in a self-confirming equilibrium. We devise theories to understand our surrounding and take decisions, and those decisions then shape the economic environment. Theories can thus survive even if they deviate from the true structure as long as the decisions make it conform. This is a statement about a lack of uniqueness of the path to the rational expectations equilibrium. In a sense, this is not too disturbing, as long as decisions are still optimal and outcomes do not differ too much from the rational expectations first best. And if this true, we will never know what the rational expectations first best is. Of broader implications would be if the political agenda of an economist would lead an economy on an different path, on a different self-confirming equilibrium. Is this why Europe and the United States are different? Were Keynes and von Hayek that influential?
His latest opus is an introspection in our profession and how our political biases influence our modelling choices. He claims that an economist with conservative inclinations will favor a model with smaller fiscal multipliers. While the ethical thing to do would be to be driven by empirical evidence, this may just be a subconscious choice. But at least economists strive to be logically consistent, and if one choose a large multiplier, then then must also claim that demand shocks are substantial, as models with large multipliers rely on this. Looking at evidence from the Survey of Professional Forecasters, Saint-Paul finds that forecasters who believe that expansions are more inflationary also adhere to the belief that public expenses are less expansionary.
Saint-Paul goes further, though. His claim is that we live in a self-confirming equilibrium. We devise theories to understand our surrounding and take decisions, and those decisions then shape the economic environment. Theories can thus survive even if they deviate from the true structure as long as the decisions make it conform. This is a statement about a lack of uniqueness of the path to the rational expectations equilibrium. In a sense, this is not too disturbing, as long as decisions are still optimal and outcomes do not differ too much from the rational expectations first best. And if this true, we will never know what the rational expectations first best is. Of broader implications would be if the political agenda of an economist would lead an economy on an different path, on a different self-confirming equilibrium. Is this why Europe and the United States are different? Were Keynes and von Hayek that influential?
Near rational agents and house price booms
House price run-ups, especially when they appear excessive, are difficult to explain. It is it even more difficult to explain how they are not coordinated across countries in a globalized world. Indeed, right now house prices are severely depressed in the United States, while you can have strong suspicions of bubbles in China, Norway and Switzerland. Bubbles are substantial deviations from fundamentals that could be due to some deviations from rationality or herd behavior, or both. But "rationalizing" this is a major challenge because of the apparent randomness of the occurrence of such house price booms.
Klaus Adam, Pei Kuang and Albert Marcet think they have a way to explain this using the concept of internally rationally agent. Such a agent, like the economist, does not know the true process of prices but tries to infer it from past observation using Bayes' rule. The belief about prices then becomes part of the state space and leads to some sort of path dependence. With shocks that are not perfectly correlated, it is then possible for different countries to experience different paths for house prices.
Klaus Adam, Pei Kuang and Albert Marcet think they have a way to explain this using the concept of internally rationally agent. Such a agent, like the economist, does not know the true process of prices but tries to infer it from past observation using Bayes' rule. The belief about prices then becomes part of the state space and leads to some sort of path dependence. With shocks that are not perfectly correlated, it is then possible for different countries to experience different paths for house prices.
Emotions in economic interactions
How do you get people to cooperate. By increasing utility, of course, but that is difficult to measure, obviously, and there may some components beyond rationality in emotional contexts. However, we have some interesting ways to get some neurological hints about positive and negative emotions by measuring the conductance of skin. This may help to explain why people are sometimes willing to hurt themselves in order to punish others.
Mateus Joffily, David Masclet, Charles Noussair and Marie-Claire Villeval conduct an experiment where cooperation, free-riding and punishment can happen. They measure skin conductance to reveal the intensity of emotions and let players reveal whether their emotions are positive or negative. Cooperation and punishment of free-riding elicit positive emotions, the latter indicating that emotions can override self-interest. That is also because punishment relieves some of the negative emotions from observing free-riding. And one does not like being punished, which lends one to cooperate more in the future. Finally, people like being in a set-up where sanctions are possible, in particular because it allows a virtuous circle of emotions that reinforce each other and lead to more cooperation.
Mateus Joffily, David Masclet, Charles Noussair and Marie-Claire Villeval conduct an experiment where cooperation, free-riding and punishment can happen. They measure skin conductance to reveal the intensity of emotions and let players reveal whether their emotions are positive or negative. Cooperation and punishment of free-riding elicit positive emotions, the latter indicating that emotions can override self-interest. That is also because punishment relieves some of the negative emotions from observing free-riding. And one does not like being punished, which lends one to cooperate more in the future. Finally, people like being in a set-up where sanctions are possible, in particular because it allows a virtuous circle of emotions that reinforce each other and lead to more cooperation.
Inattention and bank overdrafts
It happens to everyone: you are not careful and despite having sufficient funds, your checking account is drying up at the wrong moment and you incur an overdraft fee from the bank. Oh well, you say, the penalty is somewhat stiff, but bad planning has consequences. But for those who have genuine liquidity problems or those that are really bad at planning, those fees can add up quickly and become substantial. Even on an aggregate level, it is important. Apparently, US banks earn $35 billion a year from overdraft fees, or a staggering $100 per capita.
Victor Stango and Jonathan Zinman study what can make that people avoid those fees. A lot has of course to do with education and self-discipline, thus reminders become an important tool. Indeed, they notice that people who were exposed to information about overdraft fees in surveys are less likely to incur such fees in the next month, by 12%, and this effect builds up over multiple exposures. This works best with those who need it the most: low education and low financial literacy. And as people avoid overdrafts by making fewer transactions, not increasing balances, it indicates they lower their expenses as a reaction to realizing that they may not afford that much spending. In other words, financial and economic literacy are important and should be favored.
Victor Stango and Jonathan Zinman study what can make that people avoid those fees. A lot has of course to do with education and self-discipline, thus reminders become an important tool. Indeed, they notice that people who were exposed to information about overdraft fees in surveys are less likely to incur such fees in the next month, by 12%, and this effect builds up over multiple exposures. This works best with those who need it the most: low education and low financial literacy. And as people avoid overdrafts by making fewer transactions, not increasing balances, it indicates they lower their expenses as a reaction to realizing that they may not afford that much spending. In other words, financial and economic literacy are important and should be favored.
The high welfare cost of small information failures
Are stock markets efficient in the sense that stock prices reflect all available information? This question has preoccupied finance lately as many have started to doubt the efficient market hypothesis during the latest crisis. One critical aspect of this is whether current tests of the hypothesis actually give an accurate picture, and if not whether this matters in a significant way.
Tarek Hassan and Thomas Mertens
claim that it is possible for stock markets to aggregate information properly, that small errors at the household level can accumulate and amplify if these errors are correlated, and that the welfare consequences can be substantial even if the initial errors were small. This cost emerges for a portfolio misallocation due to the higher volatility of stock prices. To get to such a result, they take a standard real business cycle model, add to it that households get a noisy private signal about future total factor productivity. They then look at the stock market for additional information to form expectations. If you allow households to be on average more optimistic than rationality in some state, and more pessimistic in others, you get the above results. Interestingly, Hassan and Mertens show that households face little incentives to correct individually for these small common errors (0.01% of average consumption), but collectively the consequences are large (2.4%). Talk about an amplification.
Tarek Hassan and Thomas Mertens
claim that it is possible for stock markets to aggregate information properly, that small errors at the household level can accumulate and amplify if these errors are correlated, and that the welfare consequences can be substantial even if the initial errors were small. This cost emerges for a portfolio misallocation due to the higher volatility of stock prices. To get to such a result, they take a standard real business cycle model, add to it that households get a noisy private signal about future total factor productivity. They then look at the stock market for additional information to form expectations. If you allow households to be on average more optimistic than rationality in some state, and more pessimistic in others, you get the above results. Interestingly, Hassan and Mertens show that households face little incentives to correct individually for these small common errors (0.01% of average consumption), but collectively the consequences are large (2.4%). Talk about an amplification.
Bubbles with collateral and infinite credit
Rational bubbles occur when people believe that prices will increase into the infinite future, which makes that they invest in more assets and prices really increase. But equilibrium models have difficulties replicating such phenomena because this increased wealth also induces, at some point, people to consume more, and then the budget constraint bites and halts the bubble. So how could one still get a rational bubble? By relaxing the budget constraint.
This is what Christopher Reicher does in a way that is reminiscent of the US before the crisis: through the provision of unlimited credit, which is possible if real estate is used as collateral. This sounds rather intuitive, as long as lenders are willing to go along. What is more interesting is that the model shows that there are monetary and fiscal policies that can prevent bubbles from happening. One is to apply the fiscal theory of the price level to credit markets, that is, to make sure the price level instantaneously responds to land prices to deflate the debt. If this is difficult to implement, and it would, another way to deflate a bubble is the make sure the returns of assets are lower by increasing interest rates of bonds, which makes them more interesting than real estate. Of course, one could also tax away the bubble. And one has first to recognize that there is a bubble.
This is what Christopher Reicher does in a way that is reminiscent of the US before the crisis: through the provision of unlimited credit, which is possible if real estate is used as collateral. This sounds rather intuitive, as long as lenders are willing to go along. What is more interesting is that the model shows that there are monetary and fiscal policies that can prevent bubbles from happening. One is to apply the fiscal theory of the price level to credit markets, that is, to make sure the price level instantaneously responds to land prices to deflate the debt. If this is difficult to implement, and it would, another way to deflate a bubble is the make sure the returns of assets are lower by increasing interest rates of bonds, which makes them more interesting than real estate. Of course, one could also tax away the bubble. And one has first to recognize that there is a bubble.
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