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Mortgage securities oversold by 15-25 percent

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Below are some quotes which support the view that mortgage assets are currently undervalued by the market. Yes, the market is inefficient — it overpriced the assets at the peak of the bubble (greed), and is currently underpricing them (fear). Both Buffet and ex-Merrill banker Ricciardi below think the mispricing is about 15-25 percent. That is, the “fear premium” currently demanded by the market is 15-25 percent below a conservative guess as to what the assets are really worth. This is the margin that can be used to recapitalize banks, perhaps without costing the taxpayer any money, simply by providing a rational buyer of last resort and injecting some confidence into the market. Note to traders: yes, this is obvious. Note to academic economists: this is yet another market failure — but of an unprecedented scale and complexity.

(Actually, 15-25 percent is not bad, and just shows that credit markets are generally more rational and data driven than equities. During the Internet bubble and collapse you had mispricings of hundreds of percent, even an order of magnitude.)

Warren Buffet interview from CNBC:

Government intervention necessary to restore confidence in the market.

If I didn’t think the government was going to act, I would not be doing anything this week. I might be trying to undo things this week. I am, to some extent, betting on the fact that the government will do the rational thing here and act promptly.

Mispricing is about 15-20 percent:

…all the major institutions in the world trying to deleverage. And we want them to deleverage, but they’re trying to deleverage at the same time. Well, if huge institutions are trying to deleverage, you need someone in the world that’s willing to leverage up. And there’s no one that can leverage up except the United States government. And what they’re talking about is leveraging up to the tune of 700 billion, to in effect, offset the deleveraging that’s going on through all the financial institutions. And I might add, if they do it right, and I think they will do it reasonably right, they won’t do it perfectly right, I think they’ll make a lot of money. Because if they don’t — they shouldn’t buy these debt instruments at what the institutions paid. They shouldn’t buy them at what they’re carrying, what the carrying value is, necessarily. They should buy them at the kind of prices that are available in the market. People who are buying these instruments in the market are expecting to make 15 to 20 percent on those instruments. If the government makes anything over its cost of borrowing, this deal will come out with a profit. And I would bet it will come out with a profit, actually.

Christopher Ricciardi, former head of Merrill’s structured credit business, in an open letter to Paulson. Note his comments illustrate the role that psychology, or animal spirits (Keynes), plays in the market.

The securitization market worked exceptionally well for decades and was the financing tool of choice for large and small institutions alike. As investments, performance for securitized assets typically exceeded corporate and Treasury bond investments for decades.

Where securitization went wrong in recent years was with subprime mortgages. These securitizations performed disastrously, causing people to mistakenly question the practice of securitization itself.

Decades of historical data were ignored, with the subprime experience exclusively driving market perceptions: The entire securitization market was effectively shut down, and this explains the depth and persistence of the ongoing credit crisis.

Government purchases of illiquid mortgage assets from the system will cost taxpayers significant sums and expose them to downside risk, without addressing this fundamental issue. Billions of dollars held by all the major institutional bond managers, hedge funds and distressed funds are already available to purchase mortgage assets.

However, in the absence of a way to finance the purchase of these assets, such funds must bid at prices which represent an attractive absolute return acceptable to their investors (15% to 25% typically), resulting in typical transaction terms that have significantly impeded the sale of mortgage securities to these funds. If these funds could finance their purchases, especially under efficient financing terms, they would still require similar returns, but would be able to buy many more assets, and bid higher prices for the assets.

Our financial system needs the capital markets and the natural power of securitization to get a jumpstart from the government. I propose using the powers granted to Treasury to create “vehicles that are authorized…to purchase troubled assets and issue obligations” under currently contemplated legislation to more efficiently address the crisis and establish a program which we might call the Federal Bond Insurance Corporation (”FBIC”), as an alternative to simply having the government directly purchase assets.

Comment re: behavioral economics. The preceding housing bubble and the current crisis are very good examples of why economics is, at a fundamental level, the study of ape psychology. On the planet Vulcan, Mr. Spock and other rational, super-smart traders and investors would have cleared this market already. But we don’t live on Vulcan. Anyone who wants to model the economy based on rational agents who can process infinite amounts of information without being subject to fear, bounded cognition, herd mentality, etc. is crazy.

When the conventional wisdom is that house prices never go down (people believed this just a couple years ago), you risk little of your reputation or self-image by investing in housing. When the conventional wisdom is that all mortgage backed securities are toxic, you must be extremely independent and strong willed to risk buying in, even if metrics suggest the market is oversold. This is simple psychology. Very few people can resist conventional wisdom, even when it’s wrong.


Written by infoproc

September 26, 2008 at 5:11 pm

Housing bubble: dynamics of a bust

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The first figure is from today’s WSJ and incorporates data from Q4 2007. The second figure appeared in the Economist some time ago and was discussed previously on this blog. Does anyone care to predict the future for bubble states like California, Florida and Arizona using the Japanese data as a guide?

Lower interest rates will not re-inflate the housing bubble (although they may affect the rate at which it deflates; note the BOJ dropped real interest rates below zero in the wake of their bust). People understand now, as they did not just a few years ago, that home prices can go down. This change in ape psychology (try putting that in your macro model!) makes all the difference.

Below is historical data compiled by Yale economist Robert Shiller showing that home prices have not on average provided attractive real returns (right hand axis is inflation adjusted returns for same house sales over time; previously discussed here — the real rate of return was 0.4% between 1890 and 2004). This is yet another example in which market participants (home buyers) made decisions based on faulty assumptions that might have been easily corrected by a modest amount of research. So much for efficient markets!

Here’s some detailed data from Case-Shiller and OFHEO indices (also from WSJ; note OFHEO only tracks conforming mortgages so has less sensitivity to the high end of the market):

Finally, it is worth noting that the subprime mortgage meltdown is merely a symptom of the real estate bubble. If home prices continue to fall we will see (as we are already beginning to) higher default rates in so-called “prime” as well as subprime mortgages.

WSJ: …I assumed, for the sake of calculations, that California prices fell 8% last quarter from the third quarter, a huge number by historic measures but not out of line with Zillow’s data. For Florida and Arizona I assumed declines of 5% and 5.5%. You could use other, more modest estimates for the recent declines: They won’t change the outcomes much. I also assumed personal incomes in these states rose in line with recent and historic averages.”

The results? In all three markets, the prices are well off their peaks when compared to incomes. But they remain far above historic averages.

Median prices in California peaked in 2006 at 13.3 times per capita incomes. Hard to believe, but true. They may be down now to about 11.1 times.

But that’s still way above the ground. Throughout most of the 80s and 90s they ranged between six and seven times incomes.

Just to get down to seven times incomes, prices would have to fall 37% tomorrow.

Those who bought at the peak of the cycle may be pinning their hopes instead on “incomes catching up” instead. But they had better be patient. Even if house prices stayed exactly where they are, it would take around 10 years for rising incomes to bring the ratios back into any sort of alignment.

Written by infoproc

February 12, 2008 at 4:40 pm

Tyler Cowen and rationality

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I recently came across the paper How economists think about rationality by Tyler Cowen. Highly recommended — a clear and honest overview.

The excerpt below deals with rationality in finance theory and strong and weak versions of efficient markets. I believe the weak version; the strong version is nonsense. (See, e.g, here for a discussion of limits to arbitrage that permit long lasting financial bubbles. In other words, capital markets are demonstrably far from perfect, as defined below by Cowen.)

Although you might think the strong version of EMH is only important to traders and finance specialists, it is also very much related to the idea that markets are good optimizers of resource allocation for society. Do markets accurately reflect the “fundamental value of corporations”? See related discussion here.

Financial economics has one of the most extreme methods in economic theory, and increasingly one of the most prestigious. Finance concerns the pricing of market securities, the determinants of market returns, the operating of trading systems, the valuation of corporations, and the financial policies of corporations, among other topics. Specialists in finance can command very high salaries in the private sector and have helped design many financial markets and instruments. To many economists, this ability to “meet a market test” suggests that financial economists are doing something right. Depending on one’s interpretation, the theory of finance makes either minimal or extreme assumptions about rationality. Let us consider the efficient markets hypothesis (EMH), which holds the status of a central core for finance, though without commanding universal assent. Like most economic claims, EMH comes in many forms, some weaker, others stronger. The weaker versions typically claim that deliberate stock picking does not on average outperform selecting stocks randomly, such as by throwing darts at the financial page. The market already incorporates information about the value of companies into the stock prices, and no one individual can beat this information, other than by random luck, or perhaps by outright insider trading.

Note that the weak version of EMH requires few assumptions about rationality. Many market participants may be grossly irrational or systematically biased in a variety of ways. It must be the case, however, that their irrationalities are unpredictable to the remaining rational investors. If the irrationalities were predictable, rational investors could make systematic extra-normal profits with some trading rule. The data, however, suggest that it is very hard for rational investors to outperform the market averages. This suggests that extant irrationalities are either very small, or very hard to predict, two very different conclusions. The commitment that one of these conclusions must be true does not involve much of a substantive position on the rationality front.

The stronger forms of EMH claim that market prices accurately reflect the fundamental values of corporations and thus cannot be improved upon. This does involve a differing and arguably stronger commitment to a notion of rationality.

Strong EMH still allows that most individuals may be irrational, regardless of how we define that concept. These individuals could literally be behaving on a random basis, or perhaps even deliberately counter to standard rationality assumptions. It is assumed, however, that at least one individual does have rational information about how much stocks are worth. Furthermore, and most importantly, it is assumed that capital markets are perfect or nearly perfect. With perfect capital markets, the one rational individual will overwhelm the influence of the irrational on stock prices. If the stock ought to be worth $30 a share, but irrational “noise traders” push it down to $20 a share, the person who knows better will keep on buying shares until the price has risen to $30. With perfect capital markets, there is no limit to this arbitrage process. Even if the person who knows better has limited wealth, he or she can borrow against the value of the shares and continue to buy, making money in the process and pushing the share price to its proper value.

So the assumptions about rationality in strong EMH are tricky. Only one person need be rational, but through perfect capital markets, this one person will have decisive weight on market prices. As noted above, this can be taken as either an extreme or modest assumption. While no one believes that capital markets are literally perfect, they may be “perfect enough” to allow the rational investors to prevail.

“Behavioral finance” is currently a fad in financial theory, and in the eyes of many it may become the new mainstream. Behavioral finance typically weakens rationality assumptions, usually with a view towards explaining “market anomalies.” Almost always these models assume imperfect capital markets, to prevent a small number of rational investors from dwarfing the influence of behavioral factors. Robert J. Shiller claims that investors overreact to very small pieces of information, causing virtually irrelevant news to have a large impact on market prices. Other economists argue that some fund managers “churn” their portfolios, and trade for no good reason, simply to give their employers the impression that they are working hard. It appears that during the Internet stock boom, simply having the suffix “dot com” in the firm’s name added value on share markets, and that after the bust it subtracted value.11

Behavioral models use looser notions of rationality than does EMH. Rarely do behavioral models postulate outright irrationality, rather the term “quasi-rationality” is popular in the literature. Most frequently, a behavioral model introduces only a single deviation from classical rationality postulates. The assumption of imperfect capital markets then creates the possibility that this quasi-rationality will have a real impact on market phenomena.

The debates between the behavioral theories and EMH now form the central dispute in modern financial theory. In essence, one vision of rationality — the rational overwhelm the influence of the irrational through perfect capital markets — is pitted against another vision — imperfect capital markets give real influence to quasi-rationality. These differing approaches to rationality, combined with assumptions about capital markets, are considered to be eminently testable.

Game theory and the failed quest for a unique basis for rationality:

Game theory has shown economists that the concept of rationality is more problematic than they had previously believed. What is rational depends not only on the objective features of the problem but also depends on what actors believe. This short discussion has only scratched the surface of how beliefs may imply very complex solutions, or multiple solutions. Sometimes the relevant beliefs, for instance, are beliefs about the out-of-equilibrium behavior of other agents. These beliefs are very hard to model, or it is very hard to find agreement among theorists as to how they should be modeled.

In sum, game theorists spend much of their time trying to figure out what rationality means. They are virtually unique amongst economists in this regard. Game theory from twenty years ago pitted various concepts of rationality against each other in purely theoretical terms. Empirical results had some feedback into this process, such as when economists reject Nash equilibrium for some of its counterintuitive predictions, but it remains striking how much of the early literature does not refer to any empirical tests. This enterprise has now become much more empirical, and more closely tied to both computational science and experimental economics.

Computational economics and the failed quest for a unique basis for rationality:

Nonetheless it is easy to see how the emphasis on computability puts rationality assumptions back on center stage, and further breaks down the idea of a monolithic approach to rationality. The choice of computational algorithm is not given a priori, but is continually up for grabs. Furthermore the choice of algorithm will go a long way to determining the results of the model. Given that the algorithm suddenly is rationality, computational economics forces economists to debate which assumptions about procedural rationality are reasonable or useful ones.

The mainstream criticism of computational models, of course, falls right out of these issues. Critics believe that computational models can generate just about “any” result, depending on the assumptions about what is computable. This would move economics away from being a unified science. Furthermore it is not clear how we should evaluate the reasonableness of one set of assumptions about computability as opposed to another set. We might consider whether the assumptions yield plausible results, but if we already know what a plausible result consists of, it is not clear why we need computational theories of rationality.

As you can tell from my comments, I do not believe there is any unique basis for “rationality” in economics. Humans are flawed information processing units produced by the random vagaries of evolution. Not only are we different from each other, but these differences arise both from genes and the individual paths taken through life. Can a complex system comprised of such creatures be modeled through simple equations describing a few coarse grained variables? In some rare cases, perhaps yes, but in most cases, I would guess no. Finance theory already adopts this perspective in insisting on a stochastic (random) component in any model of security prices. Over sufficiently long timescales even the properties of the random component are not constant! (Hence, stochastic volatility, etc.)

Written by infoproc

July 30, 2007 at 4:38 pm