127 entries categorized "Economics: Behavioral"

May 12, 2008

When Hyperbolic Discounting Attacks!

Back in January, the question of whether to declare the last day of instruction here at U.C. Berkeley--May 12--part of reading period and cancel the class is a no-brainer. the students are good, enthusiastic, and well prepared. There are oceans of material to cover. The syllabus has just been hacked with a chainsaw--the half-week unit on contemporary Chinese monetary policy has just bitten the dust--and I don't wan;t to have to cut any more. And the question of whether to extend the semester and have another meeting on May 14 is also a no-brainer: it wouldn't be fair to grab normal course time for review, would it?

But today it is May 12, and this is the 44th time I have trudged into this particular course's classroom this semester. And my heart sinks at the thought that I have to do it again...

This is not to say that this has been a bad course: these are good kids, they were well-preoared, and they have learned a lot.They are still pestering me with questions about John Hicks's IS curve and John Taylor's monetary policy reaction function (which I have no covered at such length that I guessed they have to be on Friday's exam). But my marginal disutility of lecturing all of a sudden feels very high...


On a related issue, I have never been gladder that my real gradebook is in paper in my backpack then when I see this:

bSpace : My Workspace : Home

February 15, 2008

Nominal Wage Rigidity in England in the Long Run

210A Labor Markets - NeoOffice Impress

Source: Jan de Vries 2/13/08 lecture, originally from Phelps-Brown and Sheila Hopkins (1956), "Seven Centuries of the Prices of Consumables, Compared with Builders' Wage- Rates," Economica 23:92 (November), pp. 296-314 http://links.jstor.org/sici?sici=0013-0427%28195611%292%3A23%3A92%3C296%3ASCOTPO%3E2.0.CO%3B2-C
  • Extraordinarily impressive nominal wage rigidity across long spans of history.
    • Beware, however: the "ancillary" terms of the wage contract could and did vary at a much higher frequency ("we can still only pay you three pence a day, but we'll add a piece of sausage and a mug of beer at lunchtime"--that sort of thing).
  • Neverthless, aside from 1932, 1921, and 1333, nominal wages simply do not fall. It doesn't happen.

September 16, 2007

Felix Salmon Is Unhappy About Those Who Write for GM

Felix Salmon condemns the low quality of the arguments of G.M.'s advocates:

Market Movers: GM's Weak Arguments Against Increased Fuel Economy - Portfolio.com: What wonders of disingenuousness the auto industry is capable of! Right now, the Big Three are worried about proposals to mandate that they increase the fuel economy of the vehicles they sell, and so they're wheeling out economists to say that the proposals don't make sense. But one would think they could do better than this.

The economists (Robert Crandall and Hal Singer)... my favorite part of the whole piece:

If there was fuel-saving technology out there that cost $1,000 but generated $2,500 in the discounted present value of fuel savings over the life of the vehicle, carmakers would surely voluntarily embrace that technology. The carmaker could split the net benefits (equal to the difference between the discounted fuel savings and the cost of the technology) with the car buyer such that both parties to the transaction would be better off.

No need for regulation there. With large numbers of vehicle producers and well-informed consumers, the market is so efficient, in fact, that it ensures that all such transactions will occur, generating the socially optimal level of fuel economy....

"Socially optimal" only if the price of gasoline is at its socially-optimal level--which it is not. And "socially optimal" only if people buy cars entirely because they are useful, and not at all as counters in a zero-sum East African Plains Ape status game.

Crandall and Singer really ought to know better.

September 12, 2007

Handout on Greenspanism and Its Critique

Greenspanism: For and Against: http://www.j-bradford-delong.net/2007_pdf/20070912_Greenspanism

Lunch Audio File

September 04, 2007

Objects in Your Calendar Are Closer than They Appear!

Did I really just commit myself to talk in 8 days at lunch about: "Monetary Policy, the Housing Bubble, and Its Unwinding"?

MuJeung.Yang - Macro/International Brown Bag Lunch

August 30, 2007

**Justin Fox World Exclusive** **Must Credit Justin Fox**

Justin Fox writes:

The David Laibson plan for ending mortgage teaser-rate insanity - The Curious Capitalist - Justin Fox - Economy - Markets - Business - TIME: My post Tuesday on the evils of teaser-rate mortgages engendered a lot of comment. This probably had less to do with the actual content of the post than with the fact that it was linked to on the CNNMoney home page, but whatever. It's a topic folks are interested in these days, for good reason.

Now Harvard economist David Laibson, whom I mentioned in the previous post as an expert on "hyperbolic discounting"--academicspeak for the human tendency to pay too little attention to costs and benefits in the distant (and sometimes not so distant) future--has come forward with a simple proposal to end teaser madness. Here it is, a Curious Capitalist World Exclusive:

To prevent lending institutions from offering misleading deals that trap borrowers, we should require that all future mortgage loans be prepayable with no penalty. This is an easy, simple rule. The rule will have the effect of leading banks to stop offering many of the teaser rates that serve as loss leaders (pay too little interest for the first 18 months but then pay extra on the back end). These loss leaders are often confusing and tempting for borrowers. Banks won't want to offer loss leaders if borrowers can get out of the loan without paying a penalty after the subsidized payment period -- the teaser period -- ends.

My proposal would not discourage banks from offering sensible adjustable rate mortgages (those without a loss leader component). Borrowers should be allowed to take out a mortgage pegged to short-term rates. That's not a loss leader and such mortgages will still be offered if prepayment is made penalty-free. My proposal will only hit the mortgages with early loss leaders built into the payment stream.

I like it. Simple and elegant.

Don't you have to eliminate "points" as well? A lot of points plus a concessional interest rate amount to a prepayment penalty...

August 24, 2007

Algorithmic Trading Strategies Are Short the Volatility of Volatility in the Short Run, but Long the Volatility of Volatility in the Long Run

I think this from the thoughtful and intelligent Emanuel Derman is wrong:

Emanuel Derman's Blog: Algorithmic Trading Strategies: It always seemed to me, and recent occurences seem to confirm it, that most algorithmic trading strategies are long volatility but short volatility of volatility...

It seems to me that this is probably wrong in a subtle fashion. When volatility declines, the value of the current positions held by a smart algorithmic trading strategy are likely to rise--it is going to report gangbusting profits in its current accounting period. But the decline in volatility means that it has little opportunity to exploit mispricings now and in the future. So when volatility declines funds pursuing smart algorithmic trading strategies are worth less of a premium going forward. So a fall in volatility should lead them to (a) report large profits, but (b) cut their fees because they can offer less value-added in the future, and (c) reduce their scope of operations.

By contrast, a rise in volatility sees funds pursuing smart algorithmic trading strategies get absolutely hammered. But they have great opportunities going forward.

Hence we right now have the interesting spectacle of people saying today: (a) we lost half our clients' money, but (b) our strategies are sound and (c) are opportunities going forward are unbelievable, so (d) you should invest and (e) we should raise our fees because we can offer more value added, and (f) we are expanding our operations.

The problem of course, is that when you have just lost half your clients' money it takes either an incredibly sophisticated or an incredibly unsophisticated investor to take that as a sign of your fundamental excellence. See, once again, Shleifer and Vishny. See also John Meriwether, trying to make these points to his investors in the LTCM context in 1998: http://delong.typepad.com/sdj/2005/06/an_historical_d.html.

August 16, 2007

Being a Chicken Is a Low-Risk Business

Chris Dillow speaks:

Stumbling and Mumbling: Chebyshev and chickens: Mr Viniar can't be that stupid. He knows financial returns are not normally distributed, but have fat tails; extreme events are more likely than a bell curve suggests. More likely, he's thinking of Chebyshev's inequality. It says that in any data sample, no more than 1/k2 of the values are more than k standard deviations away from the mean. On this view, a 25 standard deviation event is a one in 625 probability.

Does this make Mr Viniar look less stupid? No, however we cut it, [Goldman Sachs's] Mr Viniar is talking wibble. He just under-estimated risk.

There's one very stupid way of doing this. Imagine you're a chicken. Every day, the farmer feeds you. After a while, you figure: "My returns from the farmer are pretty stable, as I seem to get roughly the same amount of corn every day. Being a chicken  is a low-risk business." The following day, the farmer breaks your neck.

Any hedge fund who took default risk (say by holding CDOs) and boasted about its Sharpe ratio based on post-2003 returns would have done much the same as this; you can't measure default risk by looking at past returns. I had assumed that no-one was stupid enough to fall for this trick; one reason why I was underwhelmed by Taleb's The Black Swan - which laboured similar points - was that I thought he was just stating the bleedin' obvious. But perhaps I was wrong.

Not only were they massively exposed to subprime risk, but they didn't know that they were massively exposed to subprime risk, and they don't seem now to be able to coherently explain why they didn't know that they were massively exposed to suboprime risk.

Snatch the Pebble from My Hand, Grasshopper!

Tyler Cowen teaches Ezra Klein one of the arcana imperii:

Ezra Klein: Drinking Strategies: I'm not yet finished with my copy of Tyler Cowen's Discovering Your Inner Economist (it's very good, though!), so maybe this is included deeper into the book. But given that Cowen upholds that expensive drinks subsidizes food, particularly at fine restaurants where they make hefty margins off wine, etc, do we have any data on what the average mark-up is? If it's high, presumably the most cost-effective strategy be to forego drinking in fine establishments -- what you can't get at home is such fine cooking, and this way it's being subsidized for you. If it's relatively modest, there's certainly some added utility, even if it's partly imagined, to pairing a nice meal with good drink, so maybe it's worth it...

Alas, my highly favorable review of Discovering Your Inner Economist is still in the editorial process at the Chronicle of Higher Education.

But I will say that I did once try to convince Bob Hall at a restaurant in Palo Alto not to order wine: the fact that the wine would cost four times retail would, I said, depress me and lower my utility. Even though I wasn't paying for it, I would still feel as though I was being cheated, and as I drank the wine that would depress me more than the wine would please me.

He had two responses: (i) "You really are crazy." (ii) "Think, instead, that it's coming straight out of the Hoover Institution endowment, and order two bottles."

More than "A Commercial-Paper Hit"

Randall Smith and Henny Sender write:

A Commercial-Paper Hit Close to KKR - WSJ.com: The meltdown in mortgage markets hit Wall Street titan Kohlberg Kravis Roberts & Co. yesterday, as a KKR real-estate affiliate sought to delay repayment of $5 billion in short-term debt held by 15 money-market funds. The action at KKR Financial Holdings LLC is the biggest blowup to hit the market for commercial paper, a form of short-term debt used by companies to fund operations. Although it is designed as a haven for cash, some issuers of asset-backed commercial paper have been hit by declining values of collateral linked to subprime mortgages. The repayment delay and related losses of up to $290 million amount to a black eye for KKR founders Henry Kravis and George Roberts at a time when they are weighing a public offering and trying to complete several buyouts whose financing plans have been disrupted by the debt-market turmoil. KKR is also the latest big Wall Street name, after Bear Stearns Cos. and Goldman Sachs Group Inc., to face a situation in which an affiliate confronted losses and possible demands for debt payment or redemptions. Bear put up funds to repay creditors of a mortgage hedge fund, and Goldman pumped its own money into a money-losing hedge fund. But it wasn't clear whether KKR would consider such a step.

The news came as markets gyrated for a second day amid jitters over how far problems with the mortgage market might spread. An analyst downgrade of mortgage lender Countrywide Financial Corp. sent its shares lower and contributed to the hand-wringing over the credit markets. The Dow Jones Industrial Average fell below the 13000 mark for the first time in nearly four months, losing 167.45, or 1.3%, to 12861.47 after being up as much as 90 points during the day. KKR Financial has been hit by a pullback by banks and other lenders from investing in "jumbo" mortgages of more than $417,000, according to people familiar with the situation.... The KKR commercial-paper issuers, KKR Atlantic Funding Trust and KKR Pacific Funding Trust, asked to delay the repayment and extend the notes' maturity for up to six months, citing "the unprecedented disruption in the residential mortgage and global commercial-paper markets."

The two issuers raised money with $500 million in equity backing from KKR Financial and invested in mortgage securities based on a debt-to-equity ratio of about 20 to 1, said the people familiar with the situation. Such mortgages might fetch only 90% or less of their face value now, these people said.

KKR Financial sold some of the mortgages beginning in May, based on a decision to convert to a limited liability corporation from a real-estate investment trust, which offered favorable tax treatment but required that 75% of its assets be in real estate.... The repayment delay doesn't appear to pose an immediate threat to the money-market funds that hold the paper, said Peter Crane, a money-fund expert in Westborough, Mass. Mr. Crane said such funds must limit any single holding to 5% of assets... KKR Financial's strategy for KKR Atlantic and KKR Pacific was to issue triple-A commercial paper at low short-term rates and invest in triple-A mortgage securities, which paid slightly higher rates. However, the strategy depended on the ability to resell the mortgages on short notice, while demand has dried up unexpectedly...

This strikes me as more than a commercial paper hit: KKR must not want to borrow in the commercial paper market in the future, for it will be very hard for any bank executive to explain why they are holding it should something, anything go wrong in the future.

For KKR as an institution to want to shut itself off from this source of financing suggests that things are indeed dire in there.

August 10, 2007

Today Is a Great Day in Finance!

Today is a great day in finance! That is, it is a great intellectual day for those of us who are friends of and committed to the intellectual project of Shleifer and Vishny, for today one of their theories is made flesh, and stomps about Wall Street like Godzilla:

Andrei Shleifer and Robert W. Vishny (1997), "The Limits of Arbitrage," Journal of Finance, 52:1, pp. 35-55. Abstract: Textbook arbitrage in financial markets requires no capital and entails no risk. In reality, almost all arbitrage requires capital, and is typically risky. Moreover, professional arbitrage is conducted by a relatively small number of highly specialized investors using other people's capital. Such professional arbitrage has a number of interesting implications for security pricing, including the possibility that arbitrage becomes ineffective in extreme circumstances, when prices diverge far from fundamental values. The model also suggests where anomalies in financial markets are likely to appear, and why arbitrage fails to eliminate them...

Yes, today we have reached the limits to arbitrage: most of the people who spend their lives trying to buy low and sell high using other people's money and leverage have given up extending their positions (and so pushing prices back toward normal-time fundamentals), and are hunkered down simply hoping to survive the next month.

Whether this will have macroeconomic implications is unclear, but I would bet not. The Fed and the ECB are pegging the prices of liquid securities, and injecting as much in the way or safe, liquid, short-term assets into the system as needed to keep that so. They are also in the market in other ways. And the nightmare scenarios always involved a simultaneous collapse in the dollar and in consumer demand, and a Fed that couldn't decide whether to fight the inflation coming from rising import prices or the unemployment coming from collapsing consumer spending. Neither of those show any signs of happening.

Yet.

http://scholar.google.com/scholar?q=shleifer+vishny+limits+to+arbitrage&num=100&hl=en&c2coff=1&safe=off&client=safari&rls=en-us&pwst=1&um=1&oi=scholart

August 07, 2007

Greg Clark's New Book: "A Farewell to Alms"

Greg Clark's new book may be right, may be wrong, but it is brilliant--the pre-industrial chapters may well be the best short treatment of the topic ever.

Nicholas Wade reviews:

Review - A Farewell to Alms: For thousands of years, most people on earth lived in abject poverty, first as hunters and gatherers, then as peasants or laborers. But with the Industrial Revolution, some societies traded this ancient poverty for amazing affluence.... Gregory Clark, an economic historian at the University of California, Davis, believes that the Industrial Revolution ... occurred because of a change... people gradually developed the strange new behaviors required to make a modern economy work. The middle-class values of nonviolence, literacy, long working hours and a willingness to save.... Because they grew more common in the centuries before 1800, whether by cultural transmission or evolutionary adaptation, the English population at last became productive enough to escape from poverty, followed quickly by other countries with the same long agrarian past....

“This is a great book and deserves attention,” said Philip Hoffman, a historian at the California Institute of Technology. He described it as “delightfully provocative” and a “real challenge” to the prevailing school of thought that it is institutions that shape economic history. Samuel Bowles, an economist who studies cultural evolution at the Santa Fe Institute, said Dr. Clark’s work was “great historical sociology and, unlike the sociology of the past, is informed by modern economic theory.”...

[F]rom 1200 to 1800... the economy was locked in a Malthusian trap--each time new technology increased the efficiency of production a little, the population grew, the extra mouths ate up the surplus, and average income fell back to its former level. This income was pitifully low.... By 1790, the average person’s consumption in England was still just 2,322 calories a day, with the poor eating a mere 1,508.... “Primitive man ate well compared with one of the richest societies in the world in 1800,” Dr. Clark observes....

The Industrial Revolution... occurred when the efficiency of production at last accelerated, growing fast enough to outpace population growth and allow average incomes to rise....

[A]ncient wills... reveal[ed] a connection between wealth and the number of progeny.... Generation after generation, the rich had more surviving children than the poor.... “The modern population of the English is largely descended from the economic upper classes of the Middle Ages,” he concluded. As the progeny of the rich pervaded all levels of society, Dr. Clark considered, the behaviors that made for wealth could have spread with them. He has documented that several aspects of what might now be called middle-class values changed significantly from the days of hunter gatherer societies to 1800. Work hours increased, literacy and numeracy rose, and the level of interpersonal violence dropped.

Another significant change in behavior, Dr. Clark argues, was an increase in people’s preference for saving over instant consumption, which he sees reflected in the steady decline in interest rates from 1200 to 1800. “Thrift, prudence, negotiation and hard work were becoming values for communities that previously had been spendthrift, impulsive, violent and leisure loving,” Dr. Clark writes....

After the Industrial Revolution, the gap in living standards between the richest and the poorest countries started to accelerate, from a wealth disparity of about 4 to 1 in 1800 to more than 50 to 1 today. Just as there is no agreed explanation for the Industrial Revolution, economists cannot account well for the divergence between rich and poor nations or they would have better remedies to offer.... [T]he middle-class values needed for productivity could have been transmitted either culturally or genetically. But in some passages, he seems to lean toward evolution as the explanation. “Through the long agrarian passage leading up to the Industrial Revolution, man was becoming biologically more adapted to the modern economic world.”...

Dr. Clark’s view is that institutions and incentives have been much the same all along and explain very little....

“He deserves kudos for assembling all this data,” said Dr. Hoffman, the Caltech historian, “but I don’t agree with his underlying argument.” The decline in English interest rates, for example, could have been caused by the state’s providing better domestic security and enforcing property rights, Dr. Hoffman said, not by a change in people’s willingness to save, as Dr. Clark asserts.... Dr. Bowles, the Santa Fe economist, said he was “not averse to the idea” that genetic transmission of capitalist values is important, but that the evidence for it was not yet there.... He also took issue with Dr. Clark’s suggestion that the unwillingness to postpone consumption, called time preference by economists, had changed in people over the centuries. “If I were as poor as the people who take out payday loans, I might also have a high time preference,” he said....

“The actual data underlying this stuff is hard to dispute,” Dr. Clark said. “When people see the logic, they say ‘I don’t necessarily believe it, but it’s hard to dismiss.’”

IMHO, in all Malthusian economies downward mobility is the rule: that's what being rich buys you--enough food to feed your children. I am much more inclined to see virtuous circles--especially longer lifespan leading to a longer planning horizon and lower interest rates--and successful institutions driving changes in attitudes and the pace of technological improvement.

But the book is brilliant.

August 06, 2007

Fear of Finance II

I wound up being quite unhappy with my "fear of finance" piece, because it completely ducked one of the most important questions: why the extraordinarily outsized pay packets of the high financiers? Why doesn't competition--which sorta works elsewhere in the economy--cause us to see greatly reduced earnings? We understand, we think, why celebrities get paid so much--a combination of increasing returns in distribution, being the genuinely best in the world, and being well-known for your well-known-ness. But why financiers?

What is it that blocks effective entry and competition, exactly?

Fear of Finance

For Project Syndicate:

We are at that turn of the intellectual cycle where the world's great and good become fearful of finance: distrustful of the rich and high-paid people who live very well indeed and work behind computer screens in the cores of the world's major cities doing... well, doing something that doesn't look like work, or productive, or useful. Each turn the fears are similar: paper-shufflers are doing better than makers, speculators are doing better than managers, traders are doing better than entrepreneurs, rootless global cosmopolites are doing better than those with their toes and ancestors in the soil, arbitrageurs are doing better than accumulators, the clever are doing better than the solid, the (financial) market is more powerful than the (regulatory, bureaucratic) state. This, the current of opinion goes, is an inversion of the normal and the natural and the just. We must cast down, as Franklin Delano Roosevelt put it, the "money changers" from their "high seats in the temple of our civilization." We must "restore the ancient truths" that growing, making, managing, and inventing things should have higher status, more honor, and greater rewards than whatever it is that financiers do.

Truth to be told, there is a lot to fear in finance. The rewards to the successful are staggeringly outsized. The punishments to the unwary are brutal. The average investor in individual stocks achieves risk-adjusted returns of the overall global stock market return--call it 6% per year in inflation-adjusted terms--minus 3%. The average investor in a managed mutual fund receives the overall return minus 2%. The average investor in an index fund receives the overall return minus 0.5%. Since the average return must be average, the informed financiers pocket the vast gaps that the poor trading strategies of the uninformed and the rash open up between their returns and the average. And it is true that nothing visible is created.

Truth be told, the scale of modern global finance is staggering: more than $4T of mergers and acquisitions this year, with tradeable and (theoretically) liquid financial assets reaching perhaps $160T by the end of this year, all in a world where annual global GDP is perhaps $50T. Martin Wolf of the Financial Times quotes the McKinsey Global Institute as estimating that world financial assets, which today are more than three times world GDP, were only equal to world GDP in 1980 (and to only two-thirds of world GDP in the aftermath of World War II). And then there are the numbers that sound very large and are hard to interpret: $300T in value of "derivative" securities; $3T of wealth managed by 12,000 global "hedge funds"; $1.2T a year committed behind the screen of "private equity."

But things are created in our modern financial system: important things, and valuable things--both positive and negative.

Consider the $4T of mergers and acquisitions this year, as companies acquire and spinoff branches and divisions in the hopes of gaining synergies or market power or better management. Those owners who sell these assets will gain roughly $800B relative to what the pre-merger speculation value of their assets had been. The owners of the companies that buy--the shareholders of the acquirers--will lose roughly $300B in market value, as markets take the acquisition as a signal that managers are exuberant and uncontrolled empire-builders rather than flinty-eyed trustees maximizing payouts to shareholders. This $300B is a tax that shareholders of growing companies think is worth paying (or perhaps cannot find a way to avoid paying) for energy in their corporate executives.

There is left a net gain of roughly $500 billion in global market value. Where does this come from? We don't know. Some of it is a destructive transfer from consumers to shareholders as corporations gain more monopoly power, some of it is an improvement in efficiency coming from better management and more appropriate scales of operations, and some of it is an overpayment by those who become irrationally exuberant when companies get their names in the news that will be taken back over time as irrational exuberance dissipates. The proportions? We don't know.

Let us, however, guess that the proportions are 1/3, 1/3, 1/3. Then several conclusions follow:

The first is that, once we look outside transfers within the financial sector, the total global effects of this chunk of finance is a gain of perhaps $340B in increased real shareholder value from higher expected future profits counterbalanced by a loss of $170B in future real wages, for households will find themselves paying higher margins to companies with more market power.

Subtract one number from the other and get a net gain of $170B of added social value in 2007: it's 0.3% of world GDP, equal to the average product of 7M of the world's workers. In one sense we should as a globe be glad that we have our M&A technicians, well-paid as they are, hard at work: it is very important that businesses with lousy managements or that are operating at inefficient scale be under pressure from those who think they could do better, and can raise the money to attempt to do do so. We certainly cannot rely on shareholder democracy as our only system of corporate control.

The second conclusion is that the gross gains--fees, trading profits, and capital gains to the winners--of perhaps $800B from this year's M&A--are greatly in excess of the perhaps $170B of net gains. Governments have a very important educational, admonitory, and regulatory role to play in this business: people should know the risks and probabilities, for they may wind up among the $630B worth of losers. So far there is little sign that they do. Third, finance has long had--since before the days of J.P. Morgan it has had--an interest in stable monopolies and oligopolies with high profit margins, while the public has an interest in competitive markets with low margins. The more skeptical you are of the ability of government-run antitrust policy to offset the monopoly power-increasing effects of M&A, the more you should seek for other sources of countervailing power--which means progressive income taxation--to offset any upward leap in income inequality.

The eighteenth-century Physiocrats thought that only the farmer was productive--that the rest were somehow cheating the farmers out of their fair share. The twentieth-century Marxists thought that only the factor worker was productive--that the traders and the organizers were somehow cheating the factory workers out of their fair share. Let us educate and regulate our financial markets so that outsiders who invest are not sheared. But let us not make the mistake of fearing finance too much.

July 28, 2007

Tyler Cowen: Underappreciated Economist E. Glen Weyl

Tyler Cowen writes:

Marginal Revolution: Underappreciated economists: a continuing series: Today I will pick E. Glen Weyl, a mere Youngling, who is studying at Princeton University.  Here is his paper on neural networks, and the abstract:

I consider a potential neural basis of overconfidence, the well-documented tendency of individuals to overestimate the precision of their predictions. I present a simple, classic connectionist model for predicting a binary variable. I show that while the network initially makes weak predictions (in the middle of the probability range) regardless of input, after observing randomly generated data it learns to be overconfident in the sense that when presented with other, unrelated random data it makes strong predictions. The model matches behavioral data in that it shows overconfidence growing with experience and then, eventually, declining. The model shows how overconfidence, far from being a surprising fallacy, can be seen as a natural outgrowth of statistical over-fitting in the brain.

Glen probably won't be underappreciated for long.  Here is his seminal paper on two-sided markets (e.g., Match.com).  There is already talk he will be a leading economist of the next generation...

July 24, 2007

Regulating Hedge Funds

A piece from last January that I wanted to remember to file:

No Consensus On Regulating Hedge Funds: By Kara Scannell, Joellen Perry, and Alistair Macdonald: European officials are pushing for more disclosure of hedge-fund portfolios or a ratings system like that for corporate debt. German officials, using their chairmanship of the Group of Eight leading nations this year, are particularly aggressive. But U.S. and British officials are taking a more hands-off approach, advocating additional study and, at least in the U.S., focusing on making sure hedge funds take money only from the wealthy and sophisticated rather than on changing hedge-fund behavior to minimize risks to the global financial system....

There is a nagging worry among many regulators and central banks that hedge funds may pose a significant risk to the global financial system and could precipitate or exacerbate a monetary crisis. They have expressed a desire for a borderless solution.... Today, hedge funds are mainly regulated indirectly through the rules governing the banks and brokerage houses that they trade with and borrow from. In the United Kingdom, hedge-fund managers are required to register with the Financial Services Authority, making them subject to random inspections and examinations....

SEC Chairman Christopher Cox testified in July that "to the maximum extent possible, our actions should be nonintrusive." Timothy Geithner, president of the New York Federal Reserve, has said that it is important to monitor hedge funds but that it isn't desirable to regulate them for now. In Continental Europe, skepticism of hedge funds is greater....

In the U.S. lawmakers have turned their attention away from how funds invest toward who is investing in the funds as a way to protect vulnerable investors. Members of Congress have said they are concerned with pension investments in hedge funds, and the SEC last month proposed a rule that would limit the number of individual investors who qualify to invest in hedge funds by raising the minimum threshold of investment acumen they must meet.

There is the "guard against hedge fund-created systematic risk" point, which is a valid one. There is also the "protect vulnerable investors" point, which seems strangely misdirected: regulating hedge funds ranks perhaps 50th on the liast of steps one ought to take to protect vulnerable investors.

July 14, 2007

Books Do Furnish a Room

Tyler Cowen on books that require extra-sharp eyes:

Marginal Revolution: Which are the books with the smallest print?: Editions of Dostoyevsky and Tolstoy often have excessively small print.  Why?  The major works by those authors are long.  Larger print will make the volumes too long and thus too expensive.  Perhaps more importantly the volumes will appear too forbidding to the average buyer. But isn't miniscule type for Raskolnikov hard to read?  Ah... most of the people who buy the book don't read it.  If miniscule type gets them to stop reading sooner rather than later, you might even call it a Pareto improvement.

Self-help books almost always have reasonably large print or even ridiculously large print.  The author doesn't have much to say and the publisher wishes to pad the book so it looks real.  Furthermore most self-help books are read (at least in part), so to keep the reader happy the print should be large.

Can you think of other generalizations?

Which books are most likely to go into "Large Print" editions?

July 08, 2007

Brainless Business Reporting by Vikas Bajaj and Carole Gould

Eric Umansky is driven into shrillness by the brainless business reporting of Vikas Bajaj and Carole Gould. Don't read the New York Times. Buy the Financial Times instead: it doesn't do things like this.

Here is Eric Umansky:

Eric Umansky: Brainless Business Reporting: It is common knowledge most actively traded mutual funds are for suckers. Over the long term, the vast majority of actively traded funds underperform the overall stock market.  The key phrase is here is "long term." Plenty of funds have a good quarter here and there, but that doesn't tell you much about the fund in the end. Yes, I know. It's all very obvious.

It's just that might want to tell the New York Times business section, which today another one of its occasional (quarterly!) sections on Mutual Funds. What does it do with all its space an accumulated wisdom? Well it focuses on those funds that have done best over....the last quarter.  And delivers hyper-unintelligent copy like profiles of the genius money managers whose funds kicked butt during the quarter.  Why do they do it? My guess is that it's just something the NYT has long done and is now on auto-pilot. Plus, it makes for easy copy. And of course even easier handy, dandy brainless graphics...

July 05, 2007

Testosterone-Crazed Devil Apes Play the Ultimatum Game!

Marginal Revolution reports:

Marginal Revolution: Testosterone economics: Remember the ultimatum game?

In this game, one player divides a pot of money between himself and another.  The other then chooses whether to accept the offer.  If he rejects it, neither player benefits.  And despite the instincts of classical economics, a stingy offer (one that is less than about a quarter of the total) is, indeed, usually rejected...

Here is the latest result:

...the responders who rejected a low final offer had an average testosterone level more than 50% higher than the average of those who accepted.  Five of the seven men with the highest testosterone levels in the study rejected a $5 ultimate offer but only one of the 19 others made the same decision...

In other words, irrationality isn't just a deviation due to imperfection, we are programmed to be spiteful.  Here is information on how high testosterone levels are correlated with urges to compete and be dominant.  Here are some other correlations; should we make a few leaps and infer that women in "sheer" clothing are more likely to be spiteful?  Should you prefer to undertake joint projects with men of slight build and women in flat shoes?  Should you deliberately seek out non-hot mates, in the realization that long-run cooperativeness is of more value than short-run hotness?

June 30, 2007

Risks in the CDO Market

Felix Salmon:

Finance Blog - Market Movers by Felix Salmon: Unpacking the Risks in the CDO Market - Portfolio.com: I think it's worth teasing out exactly what the different risks in the CDO market are...[:]

First, there's the risk that holders of subprime mortgages will default on their loans. This is a known and relatively easy to quantify risk. Subprime mortgages issued in 2005 and 2006 already have high default rates, and those rates are likely to rise even higher when the mortgages reach their second birthday and higher adjustable rates start kicking in.... [T]he key risk in the market for any mortgage-backed security is not default risk but prepayment risk, and that a high mortgage default rate, in and of itself, is not necessarily particularly worrisome from the point of view of a CDO holder.

Second, there's the risk that CDO tranches, especially the riskier equity tranches and the ones with relatively low credit ratings, will start to default.... A key problem here is one of transparency: with many CDOs investing largely in other CDOs, it's very difficult often to get a handle on what the underlying cashflows are and how likely they are to be impaired.

Third, there's the discount which investors are currently demanding in order to buy illiquid securities with precious little transparency. There's talk in the market that triple-A rated CDO tranches – which, we can reasonably assume, are very unlikely to actually default – are getting bids at 270 basis points over Treasuries, or more. That huge spread is not a credit spread; rather, it's a good old-fashioned wide bid-offer spread on extremely illiquid securities. CDOs are similar in some ways to private equity, in that they tie up money for a long period of time and hope to provide excess returns over that time. They're not designed to be instruments which can be liquidated easily or quickly. If investors start being forced to liquidate their CDOs, then the price they receive might well be much lower than the actual credit risk on those CDOs might suggest.

Fourth, there's what used to be called rollover risk. If investors start liquidating their CDOs, that means there's going to be a pretty large supply of cheap CDOs on the secondary market. In turn that means that there's going to be much less demand for expensive CDOs on the primary market.... This is the credit crunch that many people are so worried about.... These four risks form a nice little circle.... But while all the risks are real, the linkages between them all are far from clear, and the different risks don't necessarily cascade onto and exacerbate each other in this way. They might – or they might not. If investors turn out to have reasonably strong stomachs, they might not want to liquidate at prices well below their entry points. And CDOs themselves, even the ones based on subprime mortgages, might not default nearly as much as homeowners. And without the passthrough mechanism of risks two and three, the vicious cycle loses a lot of its teeth.

So there is cause for concern, to be sure. But there isn't cause for panic.

June 28, 2007

CDOs: Mark-to-Model and Donner-Party Economics

Saskia Scholtes and Gillian Tett of FT on mark-to-model:

Saskia Scholtes and Gillian Tett of FT: As head of the financial stability unit at the Banque de France, Imène Rahmouni-Rousseau travelled to America this month to look at the current turmoil in the US subprime mortgage world. Although initially that had seemed an all-American saga, Ms Rahmouni suspected that French and other European investors also held assets linked to subprime securities. So on behalf of her central bank she wanted to assess the risks. What she discovered surprised her. There was little confidence about how to value the holdings. “Pricing data are difficult to obtain,” she says. It is a discovery being shared by numerous other policymakers and investors around the world as the fallout widens from a subprime lending boom, in which US banks provided vast amounts in home loans to financially stretched borrowers who put little money down and gave no proof of income. Among the casualties have been two hedge funds run by Bear Stearns, the Wall Street investment bank.

Until recently, when late payments and defaults on these mortgages spiked higher, the problem drew little attention. This was because, through the magic of so-called structured finance, risky assets such as subprime mortgages could be packaged into attractive investment products. These elaborately constructed securities, called collateralised debt obligations (CDOs), are designed to yield juicy returns while also carrying high credit ratings. They have proved popular with hedge funds as well as with longer-term investors such as pension funds and insurance companies, many of which have bought billions of dollars of such securities in recent years – thus providing the liquidity that was then channelled into mortgage loans.

But heavy losses incurred at the two Bear Stearns hedge funds as a result of such financial haute couture have prompted fears that the CDO emperor may turn out to have no clothes. Such a revelation could threaten the value of investor portfolios around the globe – not just in the mortgage sector but in the way many sorts of company fund themselves. This is because unlike stocks listed on an exchange or US Treasury bonds, CDOs are rarely traded. Indeed, a distinct irony of the 21st-century financial world is that, while many bankers hail them as the epitome of modern capitalism, many of these new-fangled instruments have never been priced through market trading.

Instead, products such as CDOs, which are designed to be held until they mature, have often been valued in investor portfolios or on the books of investment banks according to complex mathematical models and other non-market techniques. In addition, fund managers and bankers often have broad discretion as to what kind of model they use – and thus what value is attached to their assets.

So when Wall Street creditors last week threatened fire sales of CDOs seized from the stricken Bear Stearns funds, thus creating a market price for them for the first time, they also threatened to create a wider shock for the system. Fire sales rarely realise anything close to the previously expected value of assets. But if these deals went ahead, they would provide a legitimate trading level that would challenge current portfolio valuations.

In the event, Bear Stearns’ creditors sold only a fraction of the assets put up for auction. Market participants suggest that this was in part because bids fell far below expectations, with traders increasingly reluctant to take on CDOs tainted with subprime exposure. But the crisis at Bear’s funds has left investors, brokers and regulators asking an uncomfortable question: can the pricing models that have provided the foundations for this new financial edifice really be trusted? Or will valuations turn out to be over-optimistic and result in further investor losses? “Investors are slightly more cautious, becoming more picky and asking more questions,” says Michael Ridley, co-head of high-grade debt capital markets at JPMorgan. “They want us to lift the lid off the box a bit more.”

To an extent, the valuation problem for CDOs reflects the fact that the frenetic pace of innovation seen in the financial industry this decade has outpaced the development of its infrastructure. It has often been the case that when new instruments emerge in the banking world, the market is initially quite illiquid, meaning that the level of trading is low. But the murky nature of new products has rarely had broad systemic implications, because they have typically occupied a small niche.What makes the CDO sector unusual is that it has exploded at such a breakneck pace with bankers packaging bonds, loans and other debts into ever more complex structures. Last year alone, about $1,000bn (£500bn, €745bn) in cash and derivatives CDOs was issued in Europe and the US, according to data from the Bank for International Settlements. More than one-third was composed of asset-backed securities, often including low-grade mortgages.

As this explosion has occurred, some corners of this universe have already become relatively widely traded and transparent. Every day in the London and New York markets, for example, billions of dollars worth of deals are struck involving indices of derivatives on well-known corporate bonds – making it easy to obtain prices.

However, many other such products are created by bankers directly with their clients and then simply left to sit on the books of an investor.

Since such instruments typically last three to five years – and the CDO boom is so recent – many have not come to the end of their life. Nor have they been traded. Christopher Whalen of Institutional Risk Analytics, a consultancy, says: “The lack of a publicly quoted market for CDOs and like assets is exacerbating the liquidity problems for these assets beyond the underlying economics, for example, in subprime real estate.”

To compensate, investment institutions and banks use a variety of techniques to assign a value to these instruments in their accounts. In some areas, third-party data groups exist that can offer price estimates. However, the pace of innovation is so intense that it is hard for these providers to keep up with all corners of the market. So in many cases, investors are turning to alternative techniques to create prices. One tactic used by hedge funds entails asking several brokers for price quotes and taking an average. Results vary – not least because dealer banks may hold positions in these instruments themselves.

“It is very easy for hedge funds to shop around to find valuations that suit them best and then book their assets at that,” says one banker who advises hedge funds. “Going back to the bank that sold you a CDO and asking for a price is rarely likely to produce an accurate picture.”

Another approach is to estimate valuations based on the ratings the instruments receive from credit rating agencies. Yet this does not offer a fail-safe valuation method either. The rating agencies have been downgrading bonds backed by subprime mortgages in recent weeks but critics say they have been slow to act and face difficulties in analysing the market.

Christian Stracke, analyst at CreditSights, a research company, says: “With so little truly relevant historical data on the behaviour of subprime mortgages, and with such massive structural changes having occurred in the mortgage landscape in recent years, any time-series analysis approach is little more than a not-so-educated guess.“ Moreover, while ratings attempt guidance on the chance of default, they offer no indication of how market prices could behave – as the rating agencies stress. As the BIS noted in its annual report this week, ratings reflect expected credit losses rather than the “unusually high probability” of events that “could have large effects on market values”.

That means that on the rare occasions that instruments are traded, a large gap can suddenly emerge between the market price and its book value. This week Queen’s Walk Fund, a London hedge fund, admitted it had been forced to write down the value of its US subprime securities by almost 50 per cent in just a few months. That was because when it was forced to sell them, the price achieved was far lower than the value created with the models the fund had previously used – which had been supplemented with brokers’ quotes.

But unless circumstances arise that force a market trade, valuations often remain at the investment managers’ discretion. While managers say they strive to assign honest values, these are often difficult for an outside accountant to verify, since the techniques used are invariably highly complex. Moreover, incentives do not always encourage fair valuations: hedge fund managers, for example, are typically paid a percentage of the profits they book, giving them a vested interest in reporting a high asset valuation. At best, this means that the valuations of CDOs, for example, may often lag behind any swings in broader asset classes; at worst, this ambiguity may enable hedge fund managers or investment bankers to keep posting profits – even when markets fall.

But Amitabh Arora, head of interest rate strategies at Lehman Brothers, points to a further potential impact from the Bear Stearns upheaval. “The bigger risk now is that it calls into question CDOs as a financing vehicle in the corporate credit market – I think in the next six to 12 months we will see a significant reassessment of CDOs as a financial vehicle not just in the subprime world but the corporate world too.”

Adil Abdulali, a risk manager at Protégé Partners, a fund of funds, recently studied the performance of hedge funds and discovered clear statistical indications that they tend to stage-manage their earnings [known in the industry as “smoothing” them] when they trade illiquid instruments. “Conservatively, 30 per cent of funds trading illiquid securities smooth their returns,” says Mr Abdulali.

Some bankers and policymakers argue that this is simply a teething problem that will fade as structured finance becomes more mature. History suggests that most opaque, illiquid markets eventually become more transparent when they grow large enough – and behind the scenes, the Bear Stearns hedge fund problems are prompting bankers and investment managers to re-examine their valuation techniques. “We are getting a lot of calls from worried people,” says one third-party data provider.

However, history also shows that large-scale structural dislocations – such as a serious mispricing of assets – are rarely corrected in an orderly manner. Thus the big risk now is that if thousands of banks and investment groups suddenly have to slash the value of the securities they hold, the wave of accounting losses might at best leave investors wary of purchasing all manner of complex financial instruments. At worst, it could trigger more distressed sales and a broader repricing of financial assets, not just in the subprime sector but in other illiquid markets too.

“If every CDO [manager] was forced to mark to market their subprime holdings, it would be – well, I can’t think of a strong enough word to describe what it would be,” confesses a US policymaker.

These assets do have finite lifetimes. Unless nominal asset values crash over the next five years, CMOs and CDOs held for the next five years until maturity will pay off at or close to their model value. Only those with faulty capital structures who are thus illiquid today are in trouble, and they aren't in big trouble unless the numbers of those willing, rich, liquid enough to take on the risk of holding more CDOs and CMOs and with the analytical capability to price them are small.

As long as underlying asset values don't collapse, this is a redistribution: those hedge and other funds leveraged and without liquidity lose big, and those hedge and other funds that are liquid gain big. The caravan moves on, and the returns of those who make it down the California side of Donner Pass look very impressive, with the flesh-stripped bones of the illiquid and their investors scattered near Donner Lake for future archeologists to examine.

June 24, 2007

Richard Thaler: Slippery Slope Arguments Should Be Avoided Unless There Is Proof that the Slope Is Greased

Via Pinky and the Brain: Richard Thaler:

Pinky and the Brain: Richard Thaler: Libertarian Paternalism: Let's recapitulate. People make mistakes, so sometimes they can be helped. It is possible to help without coercion. That is libertarian paternalism. The concept can be and is used in both the public and private sectors. For example, in London, pedestrians from abroad are reminded by signs on the pavement to "look right" because their instincts from back home are to expect traffic to approach from the left. No one is forced to look right, but fewer pedestrians are hit by trucks.

Another example comes from Sweden, which launched a partial privatization of their social security system in 2000. The plan was open to any fund, which meant that participants faced 456 options. There was also a very well-designed default fund -- using private managers selected by the government -- that offered global diversification at very low fees (16 basis points). By any standard, both ex ante and ex post, the participants who selected their own portfolio of funds did worse than those who took the default plan. The main mistake the government made in designing this plan was to discourage participants from choosing the default fund, perhaps thinking, as Mario does, that choosing for oneself is always the best approach.

Mario thinks we are naïve about government. We think he is naïve about firms. Does he think that the companies that offered stock options to student loan officers to induce them to feature their loans had the "actual preferences" of the students at heart? Maximizing profits does not always mean maximizing the welfare of the customers.

Finally Mario seems to have a phobia about slippery slopes. I guess he thinks that if governments start with signs that say "look right," the next thing you know we will have Prohibition coming back. By the same logic, we should worry that if libertarians succeed in eliminating rent control that we will be soon down the slippery slope toward anarchy. Slippery slope arguments should be avoided unless there is proof that the slope is greased. In our case, by insisting, as we do, on only libertarian paternalism, the slope runs into a brick wall before it even gets started. And besides, what is the alternative? Inept neglect?

June 16, 2007

Marginal Revolution: Hedge Funds

Tyler Cowen writes:

Marginal Revolution: Hedge funds: I've found at least one good piece on them, by Rene Stulz, in the Spring 2007 Journal of Economic Perspectives.  I learned or reaffirmed the following:

  1. Hedge funds have existed since at least 1949.
  2. Hedge funds exist because mutual funds do not deliver "complex investment strategies."  In part this is because mutual funds are regulated.
  3. The largest mutual fund is about six times larger than the largest hedge fund.  Marketing constraints also encourage very large funds to adopt simpler and easier-to-explain strategies.
  4. Investment advisors with fewer than 15 clients do not have to register with the SEC.
  5. Regulations restrict the compensation of mutual fund advisors in various ways, typically requiring symmetric treatment of gains and losses (if a dollar of profit leads to a bonus, a dollar of loss must lead to a penalty).  That is why mutual fund managers are compensated in proportion to the size of their funds, not their performance.  This is not obviously efficient, and of course hedge funds pay for performance.
  6. Hedge funds don't have to disclose information to investors, other than by contractual agreement.
  7. Diversification and redemption requirements make it harder for mutual funds to exploit some profit opportunities, or to hedge in particular manners.
  8. The number of mutual funds that try to replicate hedge fund strategies is growing rapidly.
  9. Available data on hedge fund returns are nearly worthless.

Overall I was struck by how much hedge fund activity is an artifact of regulations, and not necessarily beneficial regulations.  Deregulating some aspects of mutual funds may be an alternative to regulation of hedge funds...

May 28, 2007

Ezra Klein Eats Barbecue on Memorial Day

First, however, he opines about the behavioral psychology of health care:

Ezra Klein: Preventive Care vs. Health Care?: Don't get me wrong, I'm fully for both preventive health measures and better public health policy. But I wouldn't get too excited over the insight that stripping lead paint from walls is a more efficient way to improve health outcomes than restructuring health care delivery.... Mark Kleiman, for instance, writes that "[a]ir quality improvement, noise reduction, better parenting... and changes in the social forces influencing diet and exercise all probably have greater bang for the buck." Than what? Probably not than encouraging the use of statins, or hypertensive drugs, or daily tablets of aspirin. There are a lot of highly effective medical interventions which are very, very cheap. But our system is very poor at incentivizing their use.

Meanwhile, the reason doctors are constantly prescribing statins along with admonitions to exercise and eat better is because using public policy to change diet and exercise habits is really, really, really hard, unless you're prepared to be very heavy-handed (i.e, outlawing trans fats in restaurants, setting portion limits, etc). Indeed, part of the problem with preventive health measures is that, rather often, they don't work very well. Like with traditional health care, some things really succeed (stripping lead out of gasoline, giving people antibiotics), and lots of things... don't. And that's to sidestep the weird reality that what drives health care politics is concern over money which, in fact, is quite rational: Folks don't want to go bankrupt, and smart politicians don't want the government to lose all space for spending on other priorities.

In any case, there is no tension between better preventive health measures and health reform -- a more integrated system would encourage preventive health, and every bill you know of that moves us towards universal health care actually has a massive amount of money, incentives, and policies going towards preventive care -- it's something everyone agrees on. But you're never going to get a focus on preventive care in the way you do on acute care: The politics of health care are about financial and medical peace of mind at the point of absolute need. They're not necessarily rational. If they were, we'd already be running laps and eating 5-11 servings of fruits and veggies, the benefits of which are fully available to us now, and which fully rational, forward-thinking beings would be going to great lengths to take advantage of. Sadly, anyone who's ever been offered decent barbecue knows how rational we are. Damn you, Capps...

Let me go run more laps--if my quadriceps will take it after this morning's climb out of the bowl of Lafayette Reservoir--and eat more vegetables...

May 19, 2007

Mathing Up "Why Bubbles Are Great for the Economy" (It Has Been Done Before Department)

Hoisted from Comments: Robert Waldmann asks, apropos of Daniel Gross's book Pop!: Why Bubbles Are Great for the Economy:

Grasping Reality with Both Hands: Brad DeLong's Semi-Daily Journal: A Review of Daniel Gross's Book "Pop": Yes, but do you know an academic economist who has formalized this argument [that bubbles are good for the economy by] writing a [formal] model in which irrationality is necessary for growth? It would not be hard. And have you asked yourself "If not me, who? If not now, when?" Posted by: Robert Waldmann | May 13, 2007 at 11:55 PM.

It was done two decades ago, Robert: a model in which the introduction of investors subject to irrational exuberance and panic can either raise or lower the economy's productive capital stock and hence enhance or diminish the economic welfare of others in the economy. The model doesn't have all the channels that Gross discusses, but it has some of them--and enough to make the point.

Unfortunately, the authors were chasing the case in which bubbles and panics were socially harmful--not the case when bubbles are beneficial to the rest of society. But that case is there in the model, if the parameter ρ is big enough and the shock variance ratio (ση2)/(σε2) is small enough.

Here's an excerpt from the core of the argument:

Size and Incidence: There are two reasons why the capital stock [in the absence of bubbles and panics] is different.... If... misperceptions... are on average bullish [i.e., prone to bubbles, investors]... on average demand [more stock].... [I]f noise traders are on average bearish [i.e., prone to panics], the equilibrium capital stock is lower.... [I]nvestors’ demands [also] depend on the risk borne.... The θ2ση2 term in the denominator of [equation] (15) captures the reduction in the [economy's] capital stock that arises from aversion to noise trader-generated price risk.... The second term dominates, and the capital stock is lower in the presence of noise traders, if:

(17) ρ/(δ -r) < (θ/((1+r)2))((ση2)/(σε2))

For ρ≤0 [i.e., a market at least as prone to panics as bubbles], it is always the case that the presence of noise traders reduces the capital stock.

Even if ρ is positive, only if both the noise trader wealth share θ is small and if noise traders’ opinions are not volatile relative to dividend risk (that is, ((ση2)/(σε2)) relatively small) is the ratio of productive capital to wealth increased because of noise traders.

A lower capital stock implies a lower average level of consumption. Since capital gains and losses on stockholdings simply redistribute wealth from one generation to another, the average level of consumption of a generation is simply:

(18) (1+r)W + K(δ-r)

which is an increasing function of the capital stock.

The reference?

J. Bradford DeLong, Andrei Shleifer, Lawrence H. Summers, and Robert J. Waldmann (1989), "The Size and Incidence of Losses from Noise Trading," Journal of Finance 44: 3 (July), pp. 681-696 http://www.j-bradford-delong.net/pdf_files/Noise_Traders_Incidence.pdf.


Note: Robert's comment--that the source of utility gains to the sophisticated in DSSW (1990) is different from the source in Gross (2007)--is completely correct. Gross argues that volatility of opinions is good. DSSW argue implicitly that irrational exuberance can be good when such exuberance is not very volatile.

May 13, 2007

A Review of Daniel Gross's Book "Pop"

By Gillian Tett:

FT.com / Arts & weekend / Books - A heresy wise investors might embrace: Almost nothing makes financial journalists salivate as much as the world “bubble”. After all, in recent years it has been considered self evident that bubbles are a bad thing for society, particularly when they burst.... But could it be that the cassandras have it all wrong and that bubbles are actually a blessing, not a curse? This is the heretical idea advanced in a provocative book, Pop! Why Bubbles are Great for the Economy, which sketches out a history of the bubbles that have swept through America over the past 150 years. The author, Daniel Gross, is a columnist who has written for a range of publications, including most recently Slate, the internet magazine which itself emerged from the 1990s dotcom bubble. It is a pedigree which gives Gross a good perspective on the follies of the 1990s.

However, he advances his thesis by also exploring episodes which may be less familiar to modern investors, such as the telegraph investment bubble of the 1840s and 1850s and the railway frenzy of the 1880s and 1890s. He also covers the housing bubble that is bursting right now in the US – and a sector he considers the next candidate for investment excess, the alternative energy world.... Gross believes that America is prone to investment bubbles partly because its government tends to have a laisser faire attitude to innovation, preferring to let private investors fund new technologies, rather than the state. Thus “in every generation, people arise to proclaim that a new technology or set of economic assumptions and financial tools promises untold riches,” Gross writes....

[T]he interesting thing, Gross argues, is what happens after the bubble bursts.. a second round of entrepreneurs usually arrives who can create something valuable out of this excess infrastructure.... Today’s ruined infrastructure, in other words, can be the building blocks of tomorrow’s innovation. This infrastructure should not be viewed purely in physical terms. What is perhaps most beneficial about a bubble, Gross argues, is that mass mania changes the way society views the world: mad fashions or wild enthusiasms can be creative. Just look at how society has become internet-savvy in less than a decade. Or how quickly the world is now converting to the alternative energy cause as investors jump on to this bandwagon. While this investment trend will probably also end in tears, it could also produce a cleaner world – even after the “green” bubble bursts.

All this is scant comfort for anybody who lost money on internet stocks – let alone those facing foreclosure on a subprime mortgage. Gross does have the grace to acknowledge how callous his argument sounds, given that burst bubbles can unleash great suffering...

May 03, 2007

Hal Varian Says: Buy and Hold

He writes:

Sometimes the Stock Does Better Than the Investor That Buys the Stock - New York Times: There’s an old adage on Wall Street: “Buy on the rumor, sell on the news.” Unfortunately, small investors do not seem to follow this rule. Terrance Odean, a finance professor at the University of California, Berkeley, has found that small individual investors tend to buy stocks when they are mentioned in the media: they buy on the news. The professional and institutional investors are happy to sell to retail investors in such periods.

A recent article in The Financial Analysts Journal by Thomas Arnold, John H. Earl Jr. and David S. North, all finance professors at the University of Richmond, called “Are Cover Stories Effective Contrarian Indicators?” offers an intriguing finding. The professors look at how a company’s stock responds to a cover story in BusinessWeek, Fortune and Forbes. They find that positive stories follow periods of positive performance and negative stories follow periods of negative performance, which admittedly is not too surprising. More interesting, they also find that the appearance of a cover story tends to signal the end of the abnormal performance.

Hence, individuals who trade on such “news” are not likely to do well.

This is not to say that articles in the financial press are not worth reading. Quite the contrary. They often provide insightful reporting and in-depth analysis. But by the time the articles have been researched, written and published, they are no longer news — the market price of the stock already reflects the company’s future prospects.

Taken together, this research offers yet more support for the time-tested investment strategy of buy and hold. Anything that you think is news is old hat to the professionals. Trying to outguess the market is a sucker’s game.

May 02, 2007

An Attack on Jeremy Siegel...

Hussman is unhappy with Jeremy Siegel:

Hussman Funds - Weekly Market Comment: April 30, 2007 - Double Counting: In a little piece of hubris published in the Financial Times by Jeremy Siegel (who is increasingly becoming a modern-day Irving Fisher), investors were told:

Since the long-term real growth of per share earnings is also only about 2 per cent, pessimists project real returns of only 4 per cent in the stock market, well below the 6.5 to 7 per cent average real returns that the historical data have indicated.

Real returns can be estimated from the earnings yield, the reciprocal of the more popular price-earnings ratio. Since stock earnings are based on real assets, the earnings yield provides a good estimate of the real return on the stock market.

In the US , the long-term average p/e ratio has been 14.4 times, which corresponds to a 6.9 per cent earnings yield. This is extremely close to the historical average real return on equities. 2007 estimates for earnings on the S&P 500 Index range from $87 to $91 per share. With the index at 1,450, this leads to a current p/e ratio of between 15.5 and 16.5 times and a corresponding earnings yield – and hence real return – of 6.0 to 6.5 per cent on S&P 500 stocks. Even though current returns on stocks look good, future stock returns may even be higher....

[W]hy does Siegel say that the earnings yield is an estimate of the real return on stocks? Think of it this way. Reported earnings subtract out depreciation, which is another way of saying that earnings are reported as if the company reinvests only enough to replace depreciation and keep its stock of productive assets constant over time. If the company were not to invest anything for growth, it would theoretically be able to pay out all of its net earnings as dividends. If earnings on the fixed stock of capital could grow at the inflation rate by virtue of monetary factors alone, you would get zero real earnings growth. Then holding valuations constant over time, the earnings yield would be a measure of the real return on stocks. Fine if you believe the assumptions. Now let's look at the data.

The first problem is that in order to produce 2% real annual growth in earnings per share, companies have historically devoted about 50% or more of their earnings to reinvestment and repurchases - over 300 basis points of that earnings yield to get 200 basis points of real growth. That's a tip-off that historically, competitive pressures have prevented earnings from simply growing at the rate of inflation without new investment. You had to invest new money to get your earnings growth up to the inflation rate. In general, once your return on invested capital falls to the point where you're willing to buy your own stock instead of making new investments, the simple earnings yield overstates probable long-term real returns (especially if the yield is based on record earnings). In fact, about 1% of the long-term real return on stocks has come from an increase in the overall level of valuation in recent decades. Absent that increase in valuations, the real return on stocks would actually have been at least 1% less than the average long-term earnings yield.

Next, the historical average p/e Siegel cites is based on trailing net earnings, not forward operating earnings. Also, current earnings figures reflect unusually wide profit margins. On the basis of trailing net earnings even modestly normalized for profit margins, the relevant p/e for the S&P 500 is currently above 20, and actually closer to 25. That puts the applicable, normalized earnings yield at about 4-5% here. Give that a 1% haircut as explained in the foregoing paragraph, and assuming that p/e valuations don't contract in the future, you could expect a long-term real return of 3-4% from stocks going forward. Add in inflation of 2-3% and the long-term nominal total return priced into stocks here (say, on a 20-30 year horizon) is probably somewhere between 5-7% annually.

Over a shorter horizon, say 5-7 years, the likely real and nominal returns on stocks will probably be lower. At GMO, Jeremy Grantham estimates (and my work largely agrees) that the real return on stocks over the coming 7 years should be about -2% annually (about zero in nominal terms). GMO calculates its estimates for a wide variety of asset classes, including bonds, foreign stocks, and so forth. Grantham noted last week that “We now show – drum roll – the first negative sloping return/risk line we have ever seen. The process of moving all asset prices to fair value over 7 years (which is how we do our 7-year forecasts) will have resulted in a world where investors are paying to take risk!”

If investors believe that stocks should be priced to deliver long-term returns of 5-7% annually, then yes, stocks might be fairly priced here.

Even optimistic assumptions and alternative models produce only modest changes to long-term expected returns. For example, optimists might take the current earnings yield of 5.5% (a trailing price/peak earnings multiple of over 18) as sustainable, assume that profit margins will never come down, assume all earnings can be paid out as dividends, and assume earnings will achieve nominal 2% growth anyway due to inflation alone. In that case, stocks would be priced to deliver a 7.5% long-term annual return. Alternatively, optimists can assume that earnings will continue to grow along the peak of their historical 6% peak-to-peak earnings channel (a point from which earnings have always been vulnerable to long periods of tepid growth), and that valuations and profit margins will remain permanently elevated. Adding in a further 1.8% dividend yield, they might even estimate stocks to be priced for a 7.8% annual return.

It's very difficult, however, for a reasonable analysis to project long-term returns on stocks much higher than about 7.8% over a 20-30 year horizon. Again, 5-7% is more likely in my estimation, with nominal total returns on stocks close to zero over the coming 5-7 years.

The criticisms appear to be three:

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