Macon Money

Among the many fascinating people currently affiliated with the Microsoft Research New York lab is Kati London, judged by MIT's Technology Review Magazine (2010) to be among the “Top 35 Innovators Under 35.” Through her involvement with the start-up area/code, Kati has developed games that transform the individuals who play them and the communities in which they reside.

One such project is Macon Money, an initiative involving the Knight Foundation and the College Hill Alliance in Macon, Georgia. This simple experiment, amazingly enough, sheds light on some fundamental questions in monetary economics, helps explain why conventional monetary policy via asset purchases has recently been so ineffective in stimulating the economy, suggests alternative approaches that might be substantially more effective, and speaks to the feasibility of the Chicago Plan (originally advanced by Henry Simons and Irving Fisher, and recently endorsed by a couple of IMF economists) to abolish privately issued money.

So what exactly was the Macon Money project? It began with a grant of $65,000 by the Knight Foundation, which was used to back the issue of bonds. These bonds were (literally) sliced in two and the halves were given away through various channels to residents of Macon. If a pair of individuals holding halves of the same bond could find each other, they were able to exchange the (now complete) bond for Macon Money, which could then be used to make expenditures at a variety of local businesses. These business were happy to accept Macon Money because it could be redeemed at par for US currency.

The basic idea is described here:

The demographics of the participant population, the distribution of expenditures, and the strategies used by players to find their "other halves" are all described in an evaluation summary. The project had the twin goals of building social capital and stimulating economic development. Although few enduring ties were created among the players, participation did create a sense of excitement about Macon and greater optimism about its future. And participating businesses managed to find a new pool of repeat customers.

Macon money was a fiscal intervention (an injection of funds into the locality) accomplished using the device of privately issued money convertible at par. There was a temporary increase in the local money supply which was extinguished when businesses redeemed their notes. An interesting thought experiment is to imagine what would have happened if, instead of being convertible at par, businesses could only convert Macon Money into currency at a small discount.

Businesses that accept credit card payments are exactly in this situation, facing a haircut of 1-3 percent when they convert credit card payments into cash. Most businesses that participated in the original experiment would therefore likely continue to participate in the modified one. After all, businesses involved in Groupon campaigns accept a 75% haircut once Groupon takes its share of the discounted price.

But there is one critically important difference between Macon Money and a credit card payment: the former is negotiable while the latter is not. That is, instead of being redeemed at a small discount, Macon Money could be spent at par. If enough businesses were participating, it would make sense for each one to spend rather than redeem its receipts. The privately issued money would therefore remain in circulation.

What about a business that had no interest in spending its receipts on locally provided goods and services? Even in this case, there would be better alternatives to redeeming at a discount. For instance, if the discount were 3%, there would be room for the emergence of a local intermediary who offered cash at a more attractive 2% discount to the business, and then sold Macon Money at 1% below par to those who did wish to spend locally. Again, the privately issued money would remain in circulation.

As a result, the local money supply would have grown not just for a brief period, but indefinitely. The discount itself would allow for more money to be injected for any given amount of backing funds. And as long as convertibility was never in doubt, substantially more money could be issued than the funds earmarked to back it.

This simple thought experiment tells us something about policy. Macon Money provided an injection of liquidity that improved the balance sheets of those who managed to secure bonds. This allowed for an increase in aggregate expenditure, and given the slack in local productive capacity, also an increase in production.

It was expansionary monetary policy, but quite different from the kind of policy pursued by the Federal Reserve. The Fed expands the money supply by buying securities, which leads to a change in the composition of the asset side of individual balance sheets. Higher asset prices (and correspondingly lower interest rates) are supposed to stimulate demand through increased borrowing at more attractive rates. But in a balance sheet recession, distressed borrowers are unwilling to take on more debt and the stimulative effects of such a policy are accordingly muted. This is why calls for an alternative approach to monetary policy make analytical sense.

Furthermore, the fact that Macon Money was accepted only locally meant that it could not be used for imports from other locations. The monetary stimulus was therefore not subject to the kinds of demand leakages that would arise from the issue of generalized fiat money.

Finally, the project provided a very clear illustration of the difficulty of abolishing privately issued money. Unless one were to prevent all creditworthy institutions from issuing convertible liabilities, it would be virtually impossible to halt the use of such liabilities as media of exchange. Put differently, we are always going to have a shadow banking system. But what the Macon Money initiative shows is that the creative and judicious use of private money, backed by creditworthy foundations, can revitalize communities currently operating well below their productive potential. Whether this can be done in a scalable way, with some government involvement and oversight to prevent abuse, remains unclear. But surely the idea deserves a closer look?

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Update. Another important feature of Macon Money is the fact that it cannot be used to pay down debt unless the creditors are themselves local. This means that even highly indebted households will either spend it, or pay down debt by selling their notes to someone who will. If increasing economic activity is the goal, this is vastly superior to disbursements of cash.

Joseph Cotterill asks (rhetorically) whether Macon Money is the anti-Bitcoin. Exactly right, and very well put.

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Ashwin Parameswaran has sent in the following via email (posted with permission):

Just read your post on Macon money - fascinating experiment and your thought experiment on how it could stay in circulation was equally interesting.  

On the thought experiment, there's also a possibility that if Macon money can only be converted into currency at a discount then Macon money itself would be valued at a discount. Coming back to your example on credit cards, this often happens in countries where retailers can get away with it. Lots of small retailers in India offer cash discounts even when they give you a receipt i.e. its not just a tax dodge. Many retailers in the UK simply don't accept Amex cards because of the size of the haircut they impose.  

On the broader subject of imagining various types of money, this is probably closest to private banking money whereas Bitcoin is by design closest to gold. Another experiment is the idea of pure local credit money without even the intermediation of a private bank-like entity which seems to be the idea behind Ripple although the current implementation seems to be a little different. Over the last year I've done a lot of reading on 14th-17th century English history of credit/money and its almost universally accepted that most of the local money worked largely with such peer-to-peer credit systems with gold perennially being in short supply. The section of this post titled 'Interest-Bearing Money: Debt as Money' summarises some of my reading. The first half of Carl Wennerlind’s book ‘Casualties of Credit’ is excellent and has some great references in this area. 

You could see the entire arc of the last 400 years as an exercise in making these private webs of credit more stable. So peer-to-peer credit became private banking. Then comes the lender of last resort and fiat money so that the LOLR is not constrained. At the same time we make the collateral safer and safer - govt bonds during the English Financial revolution, now MBS, bank debt etc. The irony is that now banks finance everything except what they started out financing which is SME bills of exchange/invoices. Partly the reasons are regulatory but fundamentally the risk is too idiosyncratic and "micro" in an environment where macro risks are backstopped. 

In fact here in the UK there's a lot of non-bank and even peer to peer interest in some of these spaces. See this one for invoice financing (the interest is partly because peer-to-peer lending in the UK has almost no regulatory burden, not regulated by the FSA at all). In a way this is just a modern-day reconstruction of the same system that existed in 16th-17th century England - peer-to-peer webs of credit. But with the critical difference that the system is not as elastic and doesn't really need to be. There are enough individuals, insurers etc who are more than capable of taking on the real risk and giving up their own purchasing power in the interim period for an adequate return. 

Lots to think about here. Briefly, on the issue of Macon Money being valued at a discount, this seems unlikely to me except in a secondary market for conversion into cash. Unlike credit card receipts, Macon Money is negotiable, and as long as it can be converted into goods and services at par it will be valued at par by those who plan to spend it. Of course there may be an equilibrium in which vendors themselves only accept it at a discount, which then becomes a self-sustaining practice. This would be equivalent to a selective increase in price, possible only if there is insufficient competition.

Here's more from Ashwin:

Another tangential point on the peer-to-peer credit networks in 16th century England was that although they had the downside of being perpetually fragile (there are accounts of middle-class traders feeling permanently insecure because they were always entrenched in long webs of credit), this credit money could not be hoarded by anyone. In this sense it really was the anti-gold/bitcoin. I wonder what you would need to do to Macon Money to protect against the potential leakage of being just hoarded as a store of value. This is of course what people like Silvio Gesell were concerned with (there are some excellent comments by anonymous commenter 'K' on this Nick Rowe post on the paradox of hoarding). I think there's merit to a modern money that could be a medium of exchange but could not serve as a store of wealth. I often think about what such a money could look like but at the end of the day we really need experiments and trials to figure out what could work. 

Agreed.

Haircuts on Intrade

When Intrade halted trading abruptly on March 10, my initial reaction was that the company had commingled member funds with its own, MF Global style, in violation of its Trust and Security Statement. I suspected that these funds were then dissipated (or embezzled), leaving the firm unable to honor requests for redemption.

The latest announcement from the company confirms that something along these lines did, in fact, occur:

We have now concluded the initial stages of our investigations about the financial status of the Company, and it appears that the Company is in a cash “shortfall” position of approximately US $700,000 when comparing all cash on hand in Company and Member bank accounts with Member account balances on the Exchange system.

A shortfall of this kind could not have emerged if member funds had been kept separate from company funds. As it stands, the exchange is technically insolvent and faces imminent liquidation.

But the company is looking for a way to "rectify this cash shortfall position" in hopes of resuming operations and returning to viability. It has requested members with large accounts to formally agree to allow the exchange to hold on to some portion of their funds indefinitely:

The Company has now contacted all members with account balances greater than $1000, and proposed a “forbearance” arrangement between these members and the Company, which if sufficient members agree, would allow the Company to remain solvent... 

By Tuesday, April 16, 2013, we expect to be able to inform our members if sufficient forbearance has been achieved. If so, we will then resume limited operations of the Company and we will be able to process requests for withdrawals as agreed. If sufficient forbearance has not been achieved, it seems extremely likely that the Company will be forced into liquidation.

So traders find themselves in a strategic situation similar to that faced by holders of Greek sovereign debt a couple of years ago. If enough members accept the proposed haircut, then the remaining members (who do not accept) will be able to withdraw their funds. The company might then be able to resume operations and eventually allow unrestricted withdrawals. But if enough forbearance is not forthcoming, the company will be forced into immediate liquidation.

What should one do under such circumstances? As Jeff Ely might say, consider the equilibrium.  The best case outcome from the perspective of any one member would be immediate reimbursement in full. But this can only happen if the member in question denies the company's request, while enough other members agree to it. As long as members can't coordinate their actions, and each believes that his own choice is unlikely to be decisive, it makes no sense for any of them to accept the haircut. Liquidation under these circumstances seems inevitable.

On the other hand, what choice do members really have? Although their funds are senior to all other claims on the firm's assets, the cash shortfall will prevent such claims from being honored in full. And since members are scattered across multiple jurisdictions and lack the power to coordinate their response, even partial recovery through litigation seems improbable. Facing little or no prospect of getting anything back anytime soon, some might choose to roll the dice one last time.

The obvious lesson in all this is that in the absence of vigorous oversight, "trust and security" statements can't really be trusted to provide security. 

Albert Hirschman and the Happiness of Pursuit

The following is the text of my remarks at a gathering in memory of Albert Hirschman, held earlier today at the Institute for Advanced Study. The event included moving recollections from members of his family, as well as tributes by Joan Scott, Jeremy Adelman, Michael Walzer, Amartya Sen, Annie Cot, Wolf Lepenies, William Sewell, James Wolfensohn, and Robbert Dijkgraaf. Fernando Henrique Cardoso could not attend but sent written remarks that were read out by Adelman. I'll update this post with links to the text or video of other speeches should any become available.

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It’s an enormous privilege to have been invited to speak at this event in memory of Albert Hirschman. Unlike most of the other speakers here, I knew Albert only from a distance, based largely on his books and interviews. I met him in person just once, though I was fortunate enough to get to know Sarah a little during my year at the Institute.

Since my connection to Albert was largely through his writing, I’d like to speak about his love of language, his gift for expression, and his approach to the written word. To Albert, words were not merely vehicles for the transmission of ideas—they were objects to be played with and molded into structures in which one could perpetually take delight.

In 1993 Albert gave an interview to a group of Italian writers, which he later translated into English and published under the title Crossing Boundaries. I’d like to quote a segment of that interview that sums up very nicely both his playful relationship with language and the great originality of his ideas. This is what he said:

I enjoy playing with words, inventing new expressions. I believe there is much more wisdom in words than we normally assume.... Here is an example.  

One of my recent antagonists, Mancur Olson, uses the expression "logic of collective action" in order to demonstrate the illogic of collective action, that is, the virtual unlikelihood that collective action can ever happen. At some point I was thinking about the fundamental rights enumerated in the Declaration of Independence and that beautiful expression of American freedom as "the right to life, liberty, and the pursuit of happiness."I noted how, in addition to the pursuit of happiness, one might also underline the importance of the happiness of pursuit, which is precisely the felicity of taking part in collective action. I simply was happy when that play on words occurred to me.

This idea of the happiness of pursuit, the pleasure that one takes in collective action, was to be a central theme in his masterpiece Exit, Voice and Loyalty, published in 1970. Two centuries earlier, Adam Smith had spoken of our propensity to "truck, barter, and exchange one thing for another." Albert Hirschman spoke instead of a propensity to protest, complain, and generally "kick up a fuss." This articulation of discontent he called Voice.

Albert believed that voice was an important factor in arresting and reversing decline in firms, organizations, and states. Economists to that point had focused on a very different mechanism, namely desertion or exit, and had argued that greater competition, in the form of greater ease of exit, was a beneficial force in maintaining high levels of organizational performance.

Albert pointed out that there was a trade-off between exit and voice; that greater ease of exit could result in a stifling of voice as the individuals most inclined to protest and complain chose to depart instead. He also observed that loyalty, provided that it was not completely blind and uncritical, could serve to delay exit and thus create the space for voice to do its work.

What Albert did in Exit, Voice and Loyalty was nothing less than to reunite two disciplines, economics and political science, which had once been closely entwined but had drifted far apart over time. And he did this not by exporting the methods of economics to the analysis of politics, as others had done, but by emphasizing the importance of political activity within the economic sphere.

This kind of interdisciplinarity permeated all of Albert’s work. He described the idea of trespassing as "basic to his thinking." Crossing boundaries came naturally to him; he was too restless and playful to be confined to a single discipline. He was also an intellectual rebel, eager to question conventional wisdom whenever he found it wanting. In fact, he did so even when the conventional wisdom had been established by his own prior work. He referred to this as a propensity to self-subversion, which he called a "permanent trait of his intellectual personality."

I recall vividly and fondly my very first contact with Albert’s work. I had just begun graduate school, having never previously studied economics, and found myself in a course on the History of Economic Thought with the legendary Robert Heilbroner. It was Heilbroner’s book The Worldly Philosophers that had steered me to economics in the first place. And there on his syllabus, alongside Smith and Ricardo and Malthus, was Albert’s book The Passions and the Interests.

I recently went back and read this extraordinary book for a second time. The twentieth anniversary edition has a foreword by Amartya Sen, who considers it to be "among the finest" of Albert’s writings. Albert himself, in the preface to this edition, notes that it’s the one book that never fell victim to his propensity to self-subversion.

There’s a memorable passage in the book where Albert discusses Adam Smith’s claim that "order and good government" came to England as the unintended consequence of a growing taste for manufactured luxuries among the feudal elite. They "bartered their whole power and authority," says Smith, for the "gratification of… vanities… for trinkets and baubles, better fit to be the playthings of children than the serious pursuits of man." Having squandered their wealth in this manner, they could no longer support their vast armies of retainers, and became incapable of "disturbing the peace" or "interrupting the regular execution of justice."

But Albert was skeptical that the feudal lords had been quite so blind to their long-term interests. He felt that Smith, always eager to uncover the unintended effects of human action, had overreached this time. And he expressed this thought as follows:

One cannot help feeling that in this particular instance, Smith overplayed his Invisible Hand.

I can just imagine the smile that spread across Albert’s face when he came up with that turn of phrase.

Albert’s work was expansive and visionary, bold and audacious, breathtakingly original and creative. But most of all, it was playful and gently irreverent. He demonstrated to us, by his own example, the happiness of intellectual pursuit. For that, more than anything else, I’ll always be grateful.

A Prediction Market Mystery

The peer-to-peer prediction market Intrade ceased operations yesterday and closed out all open positions without notice. Visitors to the site were greeted with the following mysterious message (emphasis added):

With sincere regret we must inform you that due to circumstances recently discovered we must immediately cease trading activity on www.intrade.com. 

These circumstances require immediate further investigation, and may include financial irregularities which in accordance with Irish law oblige the directors to take the following actions:

• Cease exchange trading on the website immediately.

• Settle all open positions and calculate the settled account value of all Member accounts immediately.

• Cease all banking transactions for all existing Company accounts immediately.

During the upcoming weeks, we will investigate these circumstances further and determine the necessary course of action. 

To mitigate any further risk to members’ accounts, we have closed and settled all open contracts at fair market value as of the close of business on March 10, 2013, in accordance with the Terms and Conditions of our customers’ use of the website. You may view your account details and settled account balances by logging into the website. 

At this time and until further notice, it is not possible to make any payments to members in accordance with their settled account balance until the investigations have concluded.

Translation: all open contracts have been closed out at current prices, account balances now reflect only cash positions, and no withdrawals can be made until further notice. Not a penny will be paid out to any member for the time being, no matter how large their cash balance may be.

What on earth is going on? My best guess is that the margin posted by traders was not held, as it should be, in segregated accounts separate from company funds. When bets are made on this market, both parties must post margin equal to their worst-case loss, so that neither is subject to counterparty risk. In effect, each party is taking a position against the exchange, but these positions are exactly offsetting so the exchange bears no risk. To ensure that all promised payments can be made, these funds must be held in the form of cash, insured deposits, or safe dollar-denominated securities such as Treasury bills. They cannot be invested in risky assets, and cannot be used for the payment of salaries or expenses.

All this was made clear in the exchange's so-called Trust and Security Statement:

Segregated Funds: Your funds are held in segregated accounts with banks in Ireland, and are segregated from Intrade's own corporate funds. 

Safer by Design: If the Dow Jones crashes, the New York Stock Exchange doesn't go bankrupt. In the same way, intrade doesn't lose money when an unusual result arises. Whenever you trade, intrade will 'freeze' sufficient money in your account to cover your potential losses. If you lose, we simply transfer the already frozen money from your account to a winning customer account. If you win, we pay your winnings from a losing customer account.

While this design is safe in theory, there was no mechanism in place to ensure that these commitments would, in fact, be met. When Intrade closed its doors to US residents in November, it did so in response to an action by the CFTC. I wondered at the time whether there was regulatory concern about the segregation of funds:

Even though the exchange claims to keep this margin in segregated accounts, separate from company funds, there is always the possibility that its deposits are not fully insured and could be lost if the Irish banking system were to collapse. These losses would ultimately be incurred by traders, who would then have very limited legal recourse.

Similar concerns were raised in an exchange with Dave Pennock on twitter. I thought at the time that the biggest risk came from failures in the Irish banking system, and discounted the possibility that trader margin could be deliberately co-mingled with company funds, invested in risky securities, or simply embezzled. This may have been too optimistic a view, especially given the precedent of MF Global.

If some funds have been diverted or lost, then traders face the prospect of receiving less than par on their cash balances when withdrawals eventually resume. And even if they do not suffer eventual losses, the fact that their funds are frozen for an extended period itself imposes an opportunity cost. If there's a lesson in all this, it is that markets cannot exist without trust, and trust cannot be sustained indefinitely without some sort of oversight and regulation. Reputational effects alone are simply not enough.

Why Do Groupon Campaigns Damage Yelp Ratings?

One of the many benefits of visiting Microsoft Research this semester is that I get to attend some interesting talks by computer scientists working with social and economic data. One in particular this week turned out to be extremely topical. The paper was on "The Groupon Effect on Yelp Ratings" and it was presented by Giorgios Servas Zervas.

The starting point of the analysis was this: the Yelp ratings of businesses who launch Groupon campaigns suffer a sharp and immediate decline which recovers only gradually over time, with peristent effects lasting for well over a year. The following chart sums it up:

The trend line is a 30 day moving average, but re-initialized on the launch date (so the first few points after this date average just a few observations). There is a second sharp decline after about 180 days, as the coupons are about to expire. The chart also shows the volume of ratings, which surges after the launch date. Part of the surge is driven by raters who explicitly reference Groupon (the darker volume bars). But not all Groupon users identify as such in their reviews, and about half the increase in ratings volume comes from ratings that do not reference Groupon.

As is typical of computer scientists working with social data, the number of total observations is enormous. Almost 17,000 daily deals from over 5,000 businesses in 20 cities over a six month period are included, along with review histories for these businesses both during and prior to the observational window. In addition, the entire review histories of those who rated any of these businesses during the observational window were collected, expanding the set of reviews to over 7 million, and covering almost a million distinct businesses in all.

So what accounts for the damage inflicted on Yelp ratings by Groupon campaigns? The authors explore several hypotheses. Groupon users could be especially harsh reviewers regardless of whether or not they are rating a Groupon business. Businesses may be overwhelmed by the rise in demand, resulting in a decline in quality for all customers. The service provided to Groupon users may be worse than that provided to customers paying full price. Customer preferences may be poorly matched to businesses they frequent using Groupons. Or the ratings prior to the campaign may be artificially inflated by fake positive reviews, which get swamped by more authentic reviews after the campaign. All of these seem plausible and consistent with anecdotal evidence.

One hypothesis that is rejected quite decisively by the data is that Groupon users tend to be harsh reviewers in general. To address this, the authors looked at the review histories of those who identified Groupon use for the businesses in the observational window. Most of these prior reviews do not involve Groupon use, which allows for a direct test of the hypothesis that these raters were harsh in general. It turns out that they were not. Groupon users tend to write detailed and informative reviews that are more likely to be considered valuable, cool and funny by their peers. But they do not rate businesses without Groupon campaigns more harshly than other reviewers.

What about the hypothesis of businesses being overwhelmed by the rise in demand? Since only about half the surge in reviews comes from those who explicitly reference Groupon, the remaining ratings pool together non-Groupon customers with those who don't reveal Groupon use. This makes a decline in ratings by the latter group hard to interpret. John Langford (who was in the audience) noted that if the entire surge in reviews could be attributed to Groupon users, and if undeclared and declared users had the same ratings on average, then one could infer the effect of the campaign on the ratings of regular customers. This seems worth pursuing.

Anecdotal evidence on discriminatory treatment of customers paying discounted prices is plentiful (the authors mention the notorious FTD flowers case for instance). If mistreatment of coupon-carrying customers by a few bad apples were bringing down the ratings average, then a campaign should result in a more negatively skewed distribution of ratings relative to the pre-launch baseline. The authors look for this shift in skewness and find some evidence for it, but the effect is not large enough to account for the entire drop in the average rating.

To test the hypothesis that ratings prior to a campaign are artificially inflated by fake or purchased reviews, the authors look at the rate at which reviews by self-identified Groupon users are filtered, compared with the corresponding rate for reviews that make no mention of Groupon. (Yelp allows filtered reviews to be seen, though they are harder to access and are not used in the computation of ratings). Reviews referencing Groupon are filtered much less often, suggesting that they are more likely to be authentic. If Yelp's filtering algorithm is lenient enough to let a number of fake reviews through, then the post-campaign ratings will be not just more numerous but also more authentic and less glowing.

Finally, consider the possibility of a mismatch between the preferences of Groupon users and the businesses whose offers they accept. To look for evidence of this, the authors consider the extent to which reviews associated with Groupon use reveal experimentation on the part of the consumer. This is done by comparing the business category and location to the categories and locations in the reviewer's history. Experimentation is said to occur when the business category or zipcode differs from any in the reviewer's history. The data provide strong support for the hypothesis that individuals are much more likely to be experimenting in this sense when using a Groupon than when not. And such experimentation could plausibly lead to a greater incidence of disappointment.

This point deserves further elaboration. Even without experimentation on categories or locations, an individual who accepts a daily deal has a lower anticipated valuation for the product or service than someone who pays full price. Even if the expectations of both types of buyers are met, and each feels that they have gotten what they paid for, there will be differences in the ratings they assign. To take an extreme case, if the product were available for free, many buyers would emerge who consider the product essentially worthless, and would rate it accordingly even if their expectations are met.

There may be a lesson here for companies contemplating Groupon campaigns. Perhaps the Yelp rating would suffer less damage if the discount itself were not as steep. At present there is very little variation in discounts, which are mostly clustered around 50%. So there's no way to check whether smaller discounts actually result in better ratings relative to larger discounts. But it certainly seems worth exploring, at least for businesses that depend on strong ratings to thrive.

The Groupon strategy of prioritizing growth above earnings had been criticized on the grounds that there are few barriers to entry in this industry, and no network externalities that can protect an incumbent from competition. But if the link between campaigns and ratings can't be broken, there may be deeper problems with the business model than a change of leadership or strategy can solve.

A Combinatorial Prediction Market

I'm on leave this semester, visiting Microsoft Research's recently launched New York lab. It's a lively and stimulating place and there are a number of interesting projects underway. In this post I'd like to report on one of these, a prediction market developed by a team composed of David Pennock, David Rothschild, Miroslav Dudik, Jennifer Vaughan, and Sébastien Lahaie.

This market is very different from peer-to-peer real money prediction markets such as IEM or Intrade, in that individual participants take positions not against each other but against an algorithmic market maker that adjusts prices in response to orders placed. Furthermore, a broad and complex range of events are priced, orders of arbitrary size can be met, and consistency across prices is maintained by the immediate identification and exploitation of arbitrage opportunities.

The market for Oscar predictions is now live, and it's easy to participate. You can log in with a google account (or facebook or twitter) or create a new PredictWise account. You'll be credited with 1000 points which may be used to buy a range of contracts. These include contracts on simple events, such as "Lincoln to win Best Picture." But they also include events that reference multiple categories: you can bet on the event "Argo to win Best Picture and Daniel Day-Lewis to win Best Actor in a Leading Role," or "Zero Dark Thirty to win between 3 and 5 awards" for example.

All of these contracts are priced but the price is sensitive to order size. For small orders one can buy at the currently posted odds.  For instance, for "Lincoln to win Best Picture," current odds are 10.4%, so an expenditure of 0.104 units will return 1 unit if the event occurs:

But placing a larger order, say for 1.04 units, returns less than 10:

The functional relationship between the price and quantity vectors is deterministic and satisfies three conditions: (i) the purchase of a contract (or portfolio) raises its price smoothly, (ii) this happens in such a manner as to bound the maximum possible loss incurred by the market maker, no matter how large the order size, (iii) contracts that are obvious complements, such as "Lincoln to win Best Picture" and "Lincoln not to win Best Picture" have prices that sum to 1.

What makes this market interesting is that the algorithm ensures consistency in prices across linked contracts, quickly exploiting and eliminating any arbitrage opportunities than might arise. Some of these arbitrage conditions are not immediately transparent, as the following simplified example reveals.

Suppose that there were only two Oscar categories (Best Picture and Best Director) and consider the following seven events:

1. Lincoln to win Best Picture
2. Lincoln not to win Best Picture
3. Lincoln to win Best Director
4. Lincoln not to win Best Director
5. Lincoln to win 0 Oscars
6. Lincoln to win 1 Oscar
7. Lincoln to win 2 Oscars

Let p_i denote the price of contract i, where i = 1,...,7, where each contract pays out one dollar if the event in question occurs. Clearly we must have

p₁ + p₂ =  p₃ + p₄ = 1, 

otherwise there would be an arbitrage opportunity. Similarly, we must have

p₅ + p₆ + p₇ = 1. 

Price adjustments in response to orders are such that these equalities are continuously maintained. Somewhat less obviously, we must also have

p₁ + p₃ =  p₆ + 2p₇.

If this condition were violated, then one could construct a portfolio that guaranteed a positive profit no matter what the eventual outcome may be. To see this, suppose that prices were such that

p₁ + p₃ > p₆ + 2p₇.

In this case, the following portfolio would yield a risk-free profit: buy one unit each of contracts 2, 4, and 6, and two units of contract 7. This would cost

(1 - p₁) + (1 - p₃) +  p₆ + 2p₇  < 2.

The payoff from this portfolio would be exactly 2, no matter how things turn out. If Lincoln wins no Oscars then contracts 2 and 4 each pay out one unit, if it wins one Oscar then contract 6 pays out a unit, in addition to either contract 2 or contract 4, and if it wins two Oscars then each of the two units of contract 7 pays out.

In reality, there are more than two categories for which Lincoln has been nominated, and the arbitrage conditions are accordingly more complex. The point is that whenever trades occur that cause these conditions to be violated, the algorithm itself begins to execute additional trades that exploit the opportunity, shifting prices in such a manner as to restore parity. In peer-to-peer markets this activity is left to the participants themselves; trader developed algorithms have been in widespread use on Intrade for instance.

One problem with peer-to-peer markets is that only a few contracts can have significant liquidity, and complex combinations of events will therefore not be transparently and consistently priced. But the design described here allows for the consistent valuation of any combination of events, at the cost of subjecting the market maker to potential loss. The pricing function is designed to place a bound on this loss, but it cannot be avoided entirely because market participants have access to information that the market maker lacks.

Could this be a template for markets on compound events in the future? It certainly seems possible, if the internally generated arbitrage profits are large enough to compensate for the information disadvantage faced by the market maker. But at the moment this is a research initiative, focused on evaluating the effectiveness of the mechanism for aggregating distributed information. This goal is best served by broad participation and better data, so if you have a few minutes to spare before the Oscar winners are announced on Sunday, why not log in and place a few (hypothetical) bets?

Remembering Albert Hirschman

Albert Hirschman, among the greatest of social scientists, has died. He was truly one of a kind: always trespassing, relentlessly self-subversive, and never constrained by disciplinary boundaries.

Hirschman's life was as extraordinary as his work. Born in Berlin in 1915, he was educated in French and German. He would later gain fluency in Italian, then Spanish and English. He fled Berlin for Paris in 1933, and joined the French resistance in 1939. Fearful of being shot as a traitor by advancing German forces, he took on a new identity as a Frenchman, Albert Hermant. In 1941 he migrated to the United States, met and married Sarah Hirschman, joined the US Army, and soon found himself back in Europe as part of the war effort. After the end of hostilities he was involved in the development of the Marshall Plan, and subsequently spent four years in Bogotá where many of his ideas on economic development took shape. He and Sarah were married for more than seven decades; she died in January of this year.

Not only did Hirschman write several brilliant books in what was his fourth or fifth language, he also entertained himself with the invention of palindromes. Many of these were collected together in a book, Senile Lines by Dr. Awkward, which he presented to his daughter Katya. Forms of expression mattered to him as much as the ideas themselves. In opposition to Mancur Olson, he believed that collective action was an activity that came naturally to us humans, and was thrilled to find that one could invert a phrase in the declaration of independence to express this inclination as "the happiness of pursuit."

Hirschman's intellectual contributions were varied and many but the jewel in the crown is his masterpiece Exit, Voice and Loyalty. In this one slim volume, he managed to overturn conventional wisdom on one issue after another, and chart several new directions for research. The book is concerned with the mechanisms that can arrest and reverse declines in the performance of firms, organizations, and states. It was the interplay of two such mechanisms - desertion and articulation, or exit and voice - which Hirschman considered to be of central importance.

Exit, for instance through the departure of customers or employees or citizens in favor of a rival, can alert an organization to its own decline and set in motion corrective measures. But so can voice, or the articulation of discontent. Too rapid a rate of exit can undermine voice and result in organizational collapse instead of recovery. But a complete inability to exit can make voice futile, and poor performance can continue indefinitely.

Poorly functioning organizations prefer that an exit option be available to their most strident critics, so that they are left with less demanding customers or members or citizens. Hence a moderate amount of exit can result in the worst of all worlds, "an oppression of the weak by the incompetent and an exploitation of the poor by the lazy which is the more durable and stifling as it is both unambitious and escapable." Near-monopolies with exit options for the most severely discontented can therefore function more poorly than complete monopolies. It is not surprising that many dysfunctional states welcome the voluntary exile of their fiercest internal critics.

The propensity to exit is itself determined by the extent of loyalty to a firm or state. Loyalty slows down the rate of exit and can allow an organization time to recover from lapses in performance. But blind loyalty, which stifles voice even as it prevents exit, can allow poor performance to persist. It is in the interest of organizations to promote loyalty and raise the "price of exit", but the short term gains from doing so can lead to eventual collapse as both mechanisms for recuperation are weakened.

Among Hirschman's many targets were the Downsian model of political competition and the Median Voter Theorem. Since he considered collective action to be an expression of voice, readily adopted in response to dissatisfaction, there was no such thing as a "captive voter." Those on the fringes of a political party could not be taken for granted simply because they had no exit option: the inability to exit  just strengthened their inclination to exercise voice. This they would do with relish, driving parties away from the median voter, as political leaders trade-off the fear of exit by moderates against the threat of voice by extremists.

Albert Hirschman lived a long and eventful life and was a joyfully iconoclastic thinker. His books will be read by generations to come. But he will always remain something of an outsider in the profession; his ideas are just too broad and interdisciplinary to find neat expression in models and textbooks. He was an intellectual rebel throughout his life, and it is only fitting that he remain so in perpetuity.