Friday, August 22, 2014

Reflections on The Big Short by Michael Lewis

In The Big Short Michael Lewis tells the story of the financial meltdown of 2007-2008 from the point of view of several people who saw it coming and tried to find ways to profit from it. The story involves complex financial contracts and activities such as asset-backed bonds, collateralized debt obligations (CDOs), credit default swaps, and short selling. Lewis skillfully integrates the explanation of these concepts with his tale of individuals who recognized that bonds backed by subprime mortgages (mortgages made to people with poor credit scores) would fail. As a result, the reader is not overwhelmed with technical details of complex concepts.

After reading how those who bet against the market were vindicated, several messages should remain with readers. The experts and very smart people at the center of this market had no clue as to what would happen even though the end outcome was obvious in hindsight. When those making the loans no longer had to worry about whether the loans would be repaid, the smart people should have recognized that loan originators no longer had an incentive to worry about loan quality, and thus quality would inevitably fall, ultimately resulting in high defaults. Their assumption that housing prices would only rise was reckless. It was not the smart insiders and experts who first recognized that the market was flawed. Outsiders, people often on the fringes of investing, like a California MD with Asperger's syndrome, were the first to understand the situation. Although Lewis does not explore why the insiders were so blind, it seems obvious that group thinking and wishful thinking played huge roles. The insiders had found a way to make vast amounts of money and they wanted to believe that it was sustainable, so they did. Being smart does not immunize one from self deception--rather the hubris of smart people may make them more susceptible.

The pessimists of the story, who were the realists, wanted to bet against subprime mortgage-backed securities, but they struggled to find a way to do so. Eventually they discovered credit default swaps, which in simple terms are insurance policies on bond. As long as the bond is alive, the holder of the insurance policy must pay premiums. When the bond dies or is severely injured, the owner of the policy can collect. One does not need to actually hold the bonds to have an insurance policy on them. Further, it does not seem that this way of "shorting" the market has any corrective effect, unlike in the stock market, where shorting a stock helps drive the price down.

Why were large financial institutions willing to sell these insurance policies? Again, the experts on Wall Street did not realize how risky these bonds were. In part that was because the rating agencies--Moody's, S&P, and Fitch--said they were safe. They rated the bonds based on models, and those models were based on the assumption that pooling assets reduces risk because though some will fail, most will not. That assumption is valid when the performance of assets is uncorrelated, that is, when what happens to one is independent of what happens to others, the way a second coin flip does not depend on the results of a first coin flip. When the assets are correlated, so that they tend to move together, diversification may not reduce risk. The models were flawed and the very smart people on Wall Street gamed them to get alchemy: lead was certified as gold.

When the subprime mortgages finally crashed the world-wide financial markets, those who had bet against the subprime bonds walked away rich. But so too did those who had been originating, packaging, and selling the toxic financial instruments that had wreaked havoc. The U.S. government, fearful of total economic collapse, bailed out poorly run institutions and those who had caused the carnage walked away whole. Lewis does not blame the debacle on a lack of government regulation--if those at the center of the market did not understand what was happening, there is no chance that government bureaucrats would have. Rather he stresses the importance of incentives. When investment banks were organized as partnerships, the partners would suffer huge financial losses if the firm failed, so they worried a great deal about risk. When stockholders own the financial institution, managers have incentives to worry about the short run and not so much about risk and the long run. Top managers can and do walk away from companies that they have ruined with their wealth intact; life is not fair.

The Big Short views the collapse of the market for mortgage-backed securities from a narrow perspective. Yet it is one of the best books I have read on the episode and certainly the most entertaining.

Saturday, August 16, 2014

Review of Flash Boys by Micheal Lewis

No one matches Michael Lewis' ability to take an arcane topic of finance and use it to build a narrative that is not only educational, but also a pleasure and a joy to read. In Flash Boys the arcane topic is the way that computer geeks have been able to game the newly computerized financial markets, extracting billions of dollars from investors large and small. As in his other books, he uses the experiences of real people to build the narrative, and his main character in this book is a Brad Katsuyama, who begins the story as a stock trader at the Royal Bank of Canada (RBC).

In 2006 Katsuyama noticed an anomaly in the market. He could see bids and offers in a variety of the different stock markets, but when he tried to make a trade, that stable market disappeared as if someone knew what he wanted to do before he acted. What the reader needs to know is that by 2006 the old world of individuals trading stocks on the floor of the stock exchange had disappeared, replaced by computers that matched buy and sell orders. Further, the market had fragmented, so that in addition to the old NYSE, NASDAQ, and American Stock Market, there were a dozen other markets, all matching orders with computers.

Brad Katsuyama and the reader gradually learn that high-frequency traders, doing all their trading using computer programs, had learned how to rig the new market where a few milliseconds, less than the blink of a human eye, was enough time for a computer to execute many trades. What the high-frequency traders discovered is that a buy or sell order did not arrive at all the computerized exchanges at the same time and the delay allowed for an opportunity to "front run" it. Suppose an investor wanted to buy a large block of stock and looking at the market saw that plenty of shares were offered at the various computerized exchanges. The high-frequency traders would offer a small block on the first exchange at which the order arrived and this would allow them to see what the trader wanted to do. The high-frequency traders would use this information to race to the other markets to buy up the stock before the investor's order arrived. They would then sell those shares at a higher price to the investor. Although this may sound fantastic and impossible, it became the main activity for the high-frequency traders.

To be able to game the market in this way, speed was everything. You wanted your trading computers to be as close to the market matching computers as possible, and the high-frequency traders paid the exchanges to allow their computers to be in the same building as the computers of the exchange. The price of having a company's computer in the building depended on how close it was to the computer that ran the market. The high-frequency traders also paid to get the fastest communications links because the time that it took light to travel a hundred feet could make the difference between making money and being too late to the deal.

Lewis explores all this from the view of traders trying to discover what was happening to their trades. It would have been even more interesting, perhaps, to have traveled with those who discovered how to rig the system, but they have an incentive to remain silent. After all, a reason for their success was that people did not understand what they were doing. (And even after the outsiders understood, they were often astounded that what was being done was even technically possible.)

Eventually RBC developed a software program that neutralized the high-frequency traders by sending orders to the various exchanges with time lags so that all the orders would arrive at the various exchanges simultaneously. This prevented the high-frequency traders from using their order information on one exchange to exploit them on other exchanges.

After the reader discovers that the markets are rigged, an expected reaction would be that the government needs to regulate more. Lewis dismisses this idea using one of the characters who researches scandals on Wall Street and finds "[e]very systemic market injustice arose from some loophole in a regulation created to correct some prior injustice....[T]he regulators might solve the narrow problem of front-running in the stock market by high-frequency traders, but whatever they did to solve the problem would create yet another opportunity for financial intermediaries to make money at the expense of investors." (p. 101) The current regulation that was being exploited was Regulation National Market System, passed by the SEC in 2005 and implemented in 2007 in response to abuses that surfaced in 2004.

The last part of the book describes the efforts of Brad Katsuyama to establish a new exchange, the IEX, that would be fair and constructed in a way that would not be gamed by the high-frequency traders. His main obstacle was that so many of the big players had a stake in the existing system. The exchanges made lots of money by selling fast access to the high-frequency traders. The big banks and brokerages with access to the markets made money both by establishing their own proprietary trading areas, called dark pools, and also by selling information to the high-frequency traders. However, large investors such as mutual funds were eager for this kind of exchange and by the end of the book the IEX has been launched. It had even attracted favorable attention from Goldman Sachs, where some executives thought a fairer market was in their long-term interest and who believed they could never really compete with the high-frequency traders.

Why does it all matter? The electronic markets in theory should be matching buyers and sellers so that all the benefits of the exchange accrue to them. However, the high-frequency traders have found a way to get between the buyers and sellers, extracting a bit of the gains for themselves while providing no benefit to anyone else. This is a tax on capital that takes billions of dollars from the financial markets and thereby make them less efficient in allocating capital to its most productive uses. (On the other hand, some of the fees to banks and exchanges may allow them to keep user fees lower than they would otherwise be, so some the money extracted from the investors may provide benefits.)

I highly recommend the book. Michael Lewis is an unique talent, one who can clearly explain difficult economic and financial concepts in an entertaining and engaging way.

Monday, July 21, 2014

Cognitive limitations

Cbristina Sommers on the limits of reason:

I only recently came to appreciate the limited power of logic, reason and evidence to change minds. Most of us, whether we know it or not, are driven by emotion and group loyalty. Cognitive scientists have long known about a phenomenon called “motivated reasoning”—we tend to use logic and reason, not to discover what we believe, but to confirm what we already think we know. Instead of changing our minds in the face of contradictory evidence, we are more likely to seize on rationalizations for what we already believe. I see this tendency in myself once in a while and try mightily to resist it.

Sunday, May 25, 2014

Multiplying by drawing lines

Here is a cute little trick to multiply without knowing the multiplication tables.

Monday, May 5, 2014

The dangers of scientific consensus

From the Wall Street Journal, "The Questionable Link Between Saturated Fat and Heart Disease":
Our half-century effort to cut back on the consumption of meat, eggs and whole-fat dairy has a tragic quality. More than a billion dollars have been spent trying to prove Ancel Keys's hypothesis, but evidence of its benefits has never been produced. It is time to put the saturated-fat hypothesis to bed and to move on to test other possible culprits for our nation's health woes.

Friday, March 28, 2014

Do it for Denmark

Denmark is worried about its fertility rate, though at 1.73 it is huge compared to Poland (1.33) the Ukraine (1.30), South Korea (1.25), or Singapore (0.80). It never ceases to amaze me how little people know about fertility rates and what the implications of those rates are, but it is a narrative that the mainstream press suppresses.

Sunday, March 9, 2014

Trickle down biology

Though few in number, they have an effect that affects the whole system for the better.

Saturday, February 8, 2014

People still respond to incentives

Casey Mulligan is surprised that some economists seem to have forgotten that people respond to incentives, that if you penalize work, you get less of it.

Monday, February 3, 2014

Socialism to our south

The results of socialism in Venezuela are what anyone who understands economics expects, but some citizens still prefer to believe that bad results must come for bad people:

Each day the arrival of a new item at Excelsior Gama brought Venezuelans flooding into the store: for flour, beef, sugar. Store employees and security guards helped themselves to the goods first, clogging the checkout lines, and then had to barricade the doors to hold back the surge at the entrance.
“The store owners are doing this on purpose, to increase sales,” said Marjorie Urdaneta, a government supporter who said she believes Maduro when he accuses businesses of colluding with foreign powers to wage “economic war” against him.
“He should tell the stores: Make these items available — or else,” she said.
Socialism is always in trouble because of sabotage--a favorite theme in the USSR and China under Mao. It is unfortunate that some people cannot understand that people respond to incentives.
Most Venezuelans are too busy just trying to secure the basics. Residents from the country’s interior say the shortages are even worse outside the capital.
“There’s nothing to buy where we live,” said Maria Valencia, a preschool teacher from the oil-producing hub of Maracaibo, near Venezuela’s western border, while shopping at a government-run Bicentenario supermarket where products sold by recently nationalized companies carried little heart symbols and the phrase “Made in Socialism.”
Valencia and three family members had filled their cart with corn oil, four bottles each, the maximum. “This stuff is gold,” she said.
Shoppers here were more inclined to blame the scarcities on badly behaved countrymen whom they said were trying to profit from the situation.
And while the government is trying to run the economy, it is not doing a very good job with a basic function of government:

But if the president’s fiscal policies are anything like his response to rising crime, the country looks to be in trouble.
The Jan. 6 roadside killing of former Miss Venezuela Monica Spear in a botched robbery attempt jolted a country long-numbed by one of the world’s highest homicide rates and near-total criminal impunity. 

In democracy people get the kind of government that they deserve, which may be very different from the kind of government that they want. 

Read the whole thing in the Washington Posts here.

Wednesday, January 8, 2014


I have always liked the word "penultimate" because it seems so pretentious. Why not simply say "next-to-last"? But today I found an even more pretentious word: "antepenultimate". It means "next to next to last" or "two before the last." Now I just have to figure out where I can use it.