Bebchuk on bonuses

Bonus Guarantees Can Fuel Risky Moves by Lucian Bebchuk in the WSJ:

"Financial firms seeking to attract and retain talent are reported to be making a substantial use of guaranteed bonuses, and the French Economy Minister recently called for limits on guaranteed bonuses. While many now focus on how using guaranteed bonuses affects the level of pay, it is important to recognize their effect on incentives. Guaranteed bonuses create perverse incentives to take excessive risks, and they consequently could well be worse for incentives than straight salary."

Policing the lobster commons

Lobsters are caught in traps that sit on the sea floor, marked by (and recovered via) buoys that float above, connected to the trap by a rope. Lobstermen in Maine are known for policing who sets traps where by cutting the lines (or threatening to cut the lines) of lobstermen who set traps outside of their territory. From time to time there's a question about whether the state should limit certain areas to local lobstermen. Now is such a time:

In Maine, Tensions Over Ailing Lobster Industry
"Officially, anyone with a Maine lobster license can set traps almost anywhere in state waters. Most lobstermen are allowed 800 traps each, making for a crowded ocean floor.
But unofficially, each harbor has its own boundaries, determined by local lobstermen over the decades. Newcomers often find their buoys snatched or their trap lines cut. The lobstermen who live on Maine’s rugged islands are especially territorial and known for practicing frontier justice; in one notorious case in 2000, two lobstermen fought over turf with a pitchfork and a fish gaff."
...
"The idea of a resident-only lobstering zone is not without precedent. The state approved a two-mile “conservation zone” around Monhegan Island in 1998, restricting access to local lobstermen, who had complained about interlopers from the mainland. "
...
"George Lapointe, the state’s commissioner of marine resources, said he had not yet decided whether to endorse a resident-only zone for Matinicus and had to consider the constitutional rights of all of the state’s roughly 5,800 licensed lobstermen.
“I’ve had three other islands say they’re interested in getting their own zone if we create one for Matinicus,” Mr. Lapointe said. “One of the concerns is the balkanization of lobster territories along the coast.”
He said that enforcing the zone around Monhegan had proved expensive for the state, and that while the shooting on Matinicus had put the island’s problems under a magnifying glass, lobstermen up and down Maine’s coast were hurting."

Craigslist and spam

Wired has a long article about Craigslist and its founder; the tone is simultaneously admiring and baffled: Why Craigslist Is Such a Mess. It's well worth reading.

Here's one paragraph that stood out:
"The battle flows back and forth. Captchas—distorted words that can be interpreted by humans more easily than by machines—tamed spam on craigslist for a while. Then it came back full force, not because the spammers had solved the difficult problem in artificial intelligence but because they had hacked an easier problem in global economics. I recently established a friendly email dialog with a young man in Dhaka, Bangladesh, who works on a 13-person team that creates craigslist spam. He fills in Captchas, creates new accounts with masked IP addresses, and posts ads all day long using text from a database provided by his employer, an anonymous spam king. The going price for a spam post on craigslist is about 50 cents, with large discounts for volume. When I told Buckmaster about my new friend, he took the news calmly. "These are technically sophisticated people who take pride in their work, and when we knock them down they don't just decide to go find something else to do. You could say we are breeding the perfect spammer." "

Market for short basketball players

In China, "The Dream Basketball League was set up to allow players of "shorter" stature to compete on a level playing field, with a height limit of 6ft 2in (1.88m) imposed." But it's hard to enforce the rules (since players can hunker down when measured): "Too tall" player sparks fan violence

HT: Luke Coffman (who you could hire this year, if he's not too tall).

"Girl taxi" and "Ladies Nights"

The WSJ reports 'Girl Taxi' Service Offers Haven to Beirut's Women .

"...these days the city's transport staple is facing some serious competition from a growing army of female taxi drivers, dressed in stiff-collared white shirts, dark shades, pink ties and small pink flowers tucked into their flawlessly coiffed hair.
All of them drive for Banet Taxi, or "girl taxi" in Arabic. It is Lebanon's first cab service for women, by women. You can't miss the company's signature candy-pink cars."
...
"The company is part of a regional trend. Entrepreneurs across the Middle East have recognized the business potential in offering secure transportation options for women. Banet Taxi follows on the heels of successful women-only transportation models in Dubai, Tehran and Cairo."

..."It is the promise of a safe and uneventful ride that attracts a wide range of female passengers: older women who want a quiet drive, young women out partying until late at night, and even preschoolers put in the cars by their teachers.
Passengers' reasons for choosing Banet are based, in part, on their cultural and religious backgrounds. Beirut's population breaks down roughly into thirds, Christian, Sunni and Shiite. Conservative Muslim women might take Banet Taxi to accommodate rules against traveling with unknown men. Others just want to put comfort and safety first."

While single sex markets thrive in some venues, others use gender as a basis for discriminatory pricing, with different prices for men and women. Economists mostly don't find this malign in two-sided platforms like those that provide dating opportunities, since they need to attract both genders in comparable proportions. So, for example, some clubs have 'ladies nights,' in which women are admitted for free or at a lower cover charge.

One lawyer is very annoyed by this: N.Y. Lawsuit Calls 'Ladies' Night' Discriminatory . However Roy Den Hollander "ANTI-FEMINIST LAWYER"--N.Y. Times seems to be mostly losing these cases, and has drawn this unsympathetic portrait from the New Yorker: Hey, La-a-a-dies!

Market design courses this Fall at Harvard and MIT

In a sign that market design is taking root, there are four relevant courses being offered this Fall along the banks of the Charles. (Some are planned for the Spring as well, Susan Athey will offer one at Harvard and Tayfun Sonmez will offer another at Boston College) . The Fall offerings I know of are the following.

Hanna Halaburda at HBS will teach “Economics and Strategy for Market Intermediaries and Two-Sided Platforms” (Wednesdays, 9-noon).
The main topics of the course are market intermediaries, two-sided markets, and the impact of network effects on the competitive environment. The course will combine formal economic analysis --- using theoretical models --- with case study discussions focusing on strategic considerations that companies in two-sided markets face (e.g. in on-line dating market or e-commerce).

David Parkes in SEAS will lead a seminar, CS 286r: Topics at the Interface between Computer Science and Economics Assignment, Matching and Dymamics
Monday, Wednesday 1-2.30 PM "Recent years have seen an explosion of computer-mediated markets, exchanges, and mechanisms for assignment and production. Problems of preference elicitation and optimization are coupled with concerns for incentive compatibility so that participantscannot manipulate the outcome of a mechanism in their favor. Related challenges include promoting appropriate levels of effort by participants in competition platforms, and preventing transaction failure by unreputable participants in peer production systems. Example domains span from sponsored search, to auction platforms such as eBay, to competition platforms such as TopCoder, to matching programs for medical residents and high schools, to kidney exchanges (without money)." He writes "economists are very welcome ..."

Parag Pathak at MIT will teach Topics in Game Theory, MW4-5.30 (BEGINS OCT 26) (E51-385) He writes "the course will cover advanced topics in matching, auction theory and mechanism design, with an emphasis towards areas of recent research."

Peter Coles and I will be teaching Market Design.
Economics 2056a/HBS 4150
Littauer Center M-16 Meeting Time: F., 9-12 (First meeting Friday, Sept 4)
The course "Deals with the theory and practice of market design, with prominent examples drawn from auctions, labor markets, school choice, and kidney exchange. " Here is the Syllabus, Fall 2009 (still a work in progress).

This course has been evolving since I first taught it with Paul Milgrom, and then with Estelle Cantillon. Some alumni of the course (some of whom took it as undergrads) who are presently active in market design and/or matching are Muriel Niederle, John Asker, Nicole Immorlica, Mohammad Mahdian, Michael Ostrovsky, Parag Pathak, Fuhito Kojima, Robin Lee, Mihai Manea, and Eric Budish.

Health insurance and incentive compatibility

A widely linked post, called Unconscionable Math by the blogger known as Taunter discusses why health insurance companies don't try hard to check the facts on insurance applications. (They only check your application for fraud, he claims, when you get sick enough to make really big insurance claims, and then they may be able to decline to pay if they can make the fraud claim stick.)

He draws the analogy to Las Vegas casinos, which he says don't check that gamblers are of legal age unless they win big:

"Years ago I was walking a casino floor with a casino executive. It was an incredibly detailed tour, and we got to talking about pretty much everything that came to mind about crowds and gaming. Now, a clever observer might notice that even the tolerant people of Nevada will not allow alcohol in vending machines – wouldn’t want the little ones to be able to get a Bud Light without a human being verifying their ID. But there we were in the middle of acres of blinking lights, with absolutely no one making sure that underage kids weren’t walking up to a slot machine. Indeed, they don’t card for the table games.
The executive told me you are free to play if you are underage, you just aren’t free to win. You can sit down and pump your money into the slots, and if you look presentable you can drop some chips on blackjack or craps. However, if you should happen to start winning, the pit boss or security team will come over and check your ID. The house edge is 100%."

So...be careful with those insurance applications.

Misc. organ transplant links

The links below, which I collected over some time but never turned into blog posts, all have something interesting to say about transplantation.

Should We Legalize the Market for Human Organs? An NPR debate among Sally Satel, Amy Friedman, and Lloyd Cohen (arguing for), and James Childress, Frank Delmonico, and David Rothman (arguing against).

Lingering myths discourage organ donation from American Medical News:
"Only 38% of licensed drivers have joined their states' organ donor registries, with many deterred by long-held misconceptions about how the transplant system works, according to poll results released in April."

Organ donations decline with economy from the Miami Herald.
The numbers of organ donors is down, and experts say one reason may be the recession. But "Because of legislative action, Floridians starting in July will be able to register online to be an organ donor at donatelifeflorida.org ."

In the Kidney Trade: Seller Beware
"Need a kidney? You may be able to buy one in Pakistan, which has become one of the world’s largest “kidney bazaars,” according to an article published in the May-June issue of The Hastings Center Report, a bioethics journal.
But who sells their kidneys, and what becomes of these people afterwards? The article, by two doctors and a psychologist from Karachi, paints an ugly picture of the kidney business and challenges the argument made by some that selling organs is a great financial boon to the poor and that they are grateful for the chance to do it. "

A Better Way to Get a Kidney Daniel Rose in a NY Times OpEd proposes we shift to "opt out" for deceased donors.

National Paired Donation Network (Steve Woodle) does an exchange in Pittsburgh: Kidney exchange benefits boy, 5, and woman

Larissa MacFarquhar: Paying for Kidneys
Megan McArdle: Department of Bizarre Arguments

"Exploitation" of the Poor is a Poor Reason to Ban Organ Markets from the Volokh Conspiracy

Milford men take part in four-way kidney swap (when we helped start NEPKE, only pairwise exchanges were initially feasible, but NEPKE became a pioneer in including 3- and 4-way exchanges in its optimization algorithm...)


Britain's only saviour sibling twins: At the age of two, little do they know it but Amy and Anthony Maguire are Britain's only 'saviour sibling' twins, created to be donors for their sick older brother.
Bone marrow donation requires a perfect match.
"The twins were born after IVF treatment was used to select embryos which are a match for their brother Connor so that blood taken from their umbilical cord at birth may one day be used to offer him life-saving treatment."

Organ donation to get halachic approval
A uniquely Israeli obstacle to organ donation wends its way towards resolution:
"Chief Rabbinate tries to encourage religious public to become organ donors by resolving halachic quandaries surrounding process, issuing special donor card "

Public call for organ donations (China Daily), and
China Announces Voluntary Organ Donor System (NY Times)
CD: "China launched a national organ donation system yesterday in a bid to gradually shake off its long-time dependence on executed prisoners as a major source of organs for transplants and as part of efforts to crack down on organ trafficking."...
"Currently about one million people in China need organ transplants each year while only 1 percent receive one, official statistics show.
Only about 130 people on the mainland have signed up to donate their organs since 2003, according to research on the promotion of organ donation after death by professor Chen Zhonghua with the Institute of Organ Transplantation of Tongji Hospital."...
"China issued an organ transplant law in 2007 that bans organ trafficking and only allows donations from living people to blood relatives and spouses, plus someone considered "emotionally connected."
However, organ middlemen have been faking documents in order to make a person who is desperately in need of money be considered "emotionally connected" to the recipients, reports said.
Living transplants increased to 40 percent of total transplants from 15 percent in 2006, Chen Zhonghua said.
"That's one of the daunting tasks facing us as we try to end the organ trade by establishing this system," Huang noted.
Other goals include preventing organ tourism, improving transplant quality, better defining donors' rights and satisfying patients' needs for transplants in an ethical manner."

NYT: "At least one million people in China need organ transplants each year, but only about 10,000 receive them, according to government statistics. Dr. Huang said that most of those organs — as high as 65 percent, by some estimates — are taken from death row inmates after their executions."...
"The practice of harvesting organs from executed Chinese convicts has been widely reported in the past, although it was only confirmed in 2005, by Dr. Huang, at a medical conference in Manila. The government has routinely denied other allegations that prisoners’ organs regularly found their way to the black market, often for sale to wealthy foreigners, and that executions were sometimes scheduled to coincide with the need for a specific organ.
At a news conference in Shanghai held Wednesday to unveil the new organ-donation system, one transplant surgeon was quoted by the newspaper as saying that the taking of organs from convicts was sometimes subject to corruption. "

Made in the USA, but also sold in Canada

We're advised to "think locally and act globally," and the product labels on my new shoes illustrate some of the tension between those mandates.

This label strikes a balance between the wish to be local (and sell to those Americans who prefer to "buy American"), and the wish to be global (and to sell in Canada, where the labelling laws require two languages). And the issue isn't that Canadians are (North) Americans too:

So, I'm happy to show my Solidaire des Travailleurs Americains, whose products, Fabrique aux Etats-Unis, compete in the fairly free global marketplace.

Further unraveling of pool chair reservations

Germans can now grab poolside chairs even earlier

"The German arm of Thomas Cook, Europe's second largest travel company, has been deluged with inquiries since announcing that holidaymakers at nine hotels in Turkey, Egypt and the Canary Islands can book recliners in advance for a fee.
Germans are famous around Europe for rising early to reserve recliners near the pool with their towels, and then going back to bed or eating a lengthy breakfast.
This often annoys tourists from other nations, but they will be unable to take advantage of the new service -- it is valid only for tourists booking their trips from Germany, Mathias Brandes, head of communications at Thomas Cook in Germany, said."

HT: Scott Kominers

Matchmaking for pet dogs in India

The New York Times reports on an emerging problem of dogs owned by the Indian middle class: Matchmaking in India: Canine Division

"“When a customer goes and buys a dog, 99 percent go for a male, and down the road when they need a mate, they face a problem,” Mr. Chopra said.
He tried his hand at pet matchmaking, linking males and females of the same breeds, but it was simply impossible to find matches. Most of the females remain with breeders, he said, who prefer professional stud dogs. This also helps keep the supply of popular breeds tight — if people cannot breed dogs in their backyard they cannot cut into breeders’ profits."

Dog fighting

Here's a Texas story about an undercover police operation--with the undercover policemen hosting a number of fights--that led to many arrests for conducting dog fights. After the arrests, the fighting dogs were put down. So it's a story about repugnant transactions, from several points of view...

Bringing Down the Dogmen: How a pair of undercover cops infiltrated the secret world of Houston dogfighting.

"For centuries, dogfighting was perfectly legal. In Rome’s Colosseum, gladiator dogs were pitted against one another or against other animals, including wild elephants. One of the more popular forms of entertainment in twelfth-century England was “baiting,” in which fighting dogs would be released into a ring with chained bulls and bears. In the colonial United States dogfights were common, and they continued well into the nineteenth century, with formal rules and sanctioned referees. As recently as 1881, the Ohio and Mississippi Railroad advertised special fares to a dogfight in Louisville, Kentucky.
Eventually, because of protests by such groups as the American Society for the Prevention of Cruelty to Animals, states began passing legislation that banned dogfights. By the thirties, dogfighting had been driven almost completely underground. Nevertheless, it remained a culturally ingrained phenomenon that simply refused to go away—a fact that became all too clear when Michael Vick, the quarterback of the Atlanta Falcons, was indicted by a grand jury in July 2007 for operating a dogfighting ring on his Virginia farm and later sentenced to two years in prison. The vast majority of Americans were stunned. Why, they wanted to know, would a young multimillionaire celebrity risk everything to engage in what they regarded as a barbaric practice?"

Here's an earlier post.

Update: the article is now gated (it wasn't when I read it). Here is an ungated followup article by the same author: Fight Club. Here is a followup by a different author: What Texas Monthly left out about 'bringing down the dogmen'

The education business: Stanley H. Kaplan R.I.P.

Education isn't a marketplace that supports only schools; it also supports test making companies, and test preparation companies. The founder of the big SAT prep company just passed away: here's an obit from the Chicago Trib. Stanley H. Kaplan, 1919-2009: Founded popular test-prep company.

The Atlantic has this to say. Stanley H. Kaplan's Legacy.

The Chronicle of Higher Ed's story contains this: "And as his business grew, all sorts of other commercial educational interests began to expand their influence on the academy. Today, the higher-education industry includes not only giant for-profit institutions like DeVry University, the University of Phoenix, and the degree-granting colleges of Kaplan itself, but also course-management companies like Blackboard Inc. and eCollege, distance-learning outsourcers like Higher Ed Holdings, and student-coaching and tutoring companies like Inside Track and Smartthinking."

The sending and transmitting and facilitating of signals is a big business, in college admissions as elsewhere. (Indeed, there's a big part of economic theory that looks on a college education itself as a costly signal sent by the teachable...)

Coming of Road Rage in Samoa

Unless the government backs down, Samoa will change from driving on the right to driving on the left (British Commonwealth style) on September 7:

Shifting the Right of Way to the Left Leaves Some Samoans Feeling Wronged
Government Calls Traffic-Rule Switch 'Common Sense,' but It Sparks Road Rage.

This is one of those cases in which it clearly helps everyone to have a clear rule about which side of the road to drive on, and a little government regulation (and even inter-government coordination) can promote efficient traffic flow. (Think of the congestion at the borders at which you had to switch from driving on one side to driving on the other.)

But it isn't obvious that there's a "right" side, especially since Samoa is an island, and doesn't have to coordinate with anyone who can drive to Samoa from somewhere else. (The last country in continental Europe to switch sides--from driving on the left to driving on the right--was Sweden, in 1967.) Here's a nicely written historical account (whose accuracy I can't vouch for): Why do some countries drive on the right and others on the left ?

(I particularly liked their description of the decision in Pakistan: "Pakistan also considered changing to the right in the 1960s, but ultimately decided not to do it. The main argument against the shift was that camel trains often drove through the night while their drivers were dozing. The difficulty in teaching old camels new tricks was decisive in forcing Pakistan to reject the change.")

The government of Samoa believes that the benefits of switching will come from enabling Samoans to buy used cars from the left-driving Australians and New Zealanders.

But the proposal to switch sides is not without costs, since the current stock of cars has the driver sitting on the left, which will make some things (like passing) harder if traffic is switched to the left side of the road. (And of course the current stock of school buses will have to load and unload children from the middle of the street, instead of from the curb.)

It looks like September 7 might be a good day to avoid the roads, if you happen to be in Samoa. (And here's an earlier post on New Zealand traffic rules .)
*********

Update: Samoa switches smoothly to driving on the left
"Samoa is the first country in decades to change the direction of traffic. Iceland and Sweden did it in the 1960s, and Nigeria, Ghana and Yemen did it in the 1970s."

Ecclesiastical Insurance

Before you read this post, what do you think Ecclesiastical Insurance insures against? (It turns out to have more to do with hot lead than with lost souls...)



The Church of England is under attack, and not just from the usual schismatics. Here's the story: Church of England fights fiddlers on the roof


"THE Church of England is using nanotechnology – the science of very small things – to fight thieves who strip lead and other valuable metals from the roofs of its ancient buildings.
More than 30,000 of Britain’s 44,000 churches have had their roofs coated in a layer of “nanopaint”, which is visible only under ultraviolet light.
Each church has a different blend of microscopic particles, giving its metal a unique “label”. This enables police to identify church lead found in any haul of suspect scrap, even if it has been melted down."
...
"Recently, church authorities scored a victory in the battle against thieves with the conviction of three men for stealing lead from the roof of St Leonard’s church in Colchester, Essex.
They were caught after police identified the lead stolen from the church on sale at a scrapyard by using the new labelling system."
...
"The number of insurance claims for metal thefts from churches has risen from just 12 in 2002 to more than 2,500 last year – attacks described by Peter Walley, chaplain to the bishop of Lichfield, as “the biggest asset-stripping of churches since the dissolution of the monasteries”."
...
"The demand for scrap is driven by world prices. Those for lead and copper soared to record levels last year with scrap lead peaking at £1,300 a ton. Metal prices fell when the recession hit, but are now picking up again strongly.
Most churches are insured by Ecclesiastical Insurance, which is so concerned at the losses that it recently sent every church a SmartWater kit and warned vicars and bishops it would pay out no more than £5,000 if they failed to use it on their roofs.
A spokesman for Ecclesiastical Insurance said metal theft had become the number one reason for claims. "

What if they ran an auction and nobody came?

David Fahrenthold writes in the Washington Post about Maryland's unsuccessful attempt to buy back some crab fishing licenses via an auction:
To Some Chesapeake Crabbers, a $50 Document Is Priceless
"Despite Industry's Woes, Many Watermen Refuse to Sell Symbol of Old Way of Life"

Apparently the licenses have value even to those who don't currently use them to catch crabs. The right to take crabs is what makes you a waterman...

Investing in law suits

"To press a suit" means something different to a tailor and to a lawyer. Now investors are getting involved too.

Investing in Lawsuits, for a Share of the Awards
"A small but growing number of investors are exploring this idea, helping companies avoid some of the risks and costs of litigation in exchange for part of any money paid out when the case is settled or resolved by a court."

This reflects some broader changes in the law biz, somewhat related to developments in patent and class action law.

Regarding patents, firms that invest in patents with an eye towards making money from infringement law suits are known by those who dislike them as patent trolls (see here, too). There is both an offensive and a defensive part of that business, and both attract investors, see e.g. Trolling for Patents to Fight Patent Trolls.

Another kind of lawsuits that involve investors are class action suits. Here the investors are often a consortium of law firms that can pool otherwise unbillable hours to devote to a large speculative project that will only pay off in case of a favorable decision or settlement. The theory behind class action is that it should allow the law to bear on malefactors who might harm many people, but each too little to justify the expense of an individual lawsuit. (E.g. a supermarket chain that systematically overcharged everyone twelve cents might eventually be found liable to pay damages to a large class of consumers. If you noticed them doing this, you wouldn't be able to interest a law firm in representing you as an individual plaintiff, but might be able to interest a firm in representing the whole class.) Class action law envisions the firms as responding to claims presented by plaintiffs, and a plaintiff who claims harm is needed to bring the case. But there's a big advantage to being the first firm (or consortium) to bring a class action law suit, since the originating law firms get to represent the whole class of plaintiffs. So there's a temptation for an entrepreneurial firm to go out and hire some plaintiffs, which is against the law. One of the biggest class action firms fell to this temptation: Class-Action Firm Agrees to Pay $75 Million to Settle Kickback Case

HT: Benjamin Kay, an econ grad student at UCSD

Automated spam blog detection

Woke up this morning to find this on my blog dashboard:

"This blog has been locked due to possible Blogger Terms of Service violations. You may not publish new posts until your blog is reviewed and unlocked.
This blog will be deleted within 20 days unless you request a review."

And this in my email:
"Your blog at: http://marketdesigner.blogspot.com/ has been identified as a potential spam blog. To correct this, please request a review by filling out the form at http://www.blogger.com/unlock-blog.g?lockedBlogID=4748060798655400108

Your blog will be deleted in 20 days if it isn't reviewed, and your readers will see a warning page during this time. After we receive your request, we'll review your blog and unlock it within two business days. Once we have reviewed and determined your blog is not spam, the blog will be unlocked and the message in your Blogger dashboard will no longer be displayed. If this blog doesn't belong to you, you don't have to do anything, and any other blogs you may have won't be affected.

We find spam by using an automated classifier. Automatic spam detection is inherently fuzzy, and occasionally a blog like yours is flagged incorrectly. We sincerely apologize for this error. By using this kind of system, however, we can dedicate more storage, bandwidth, and engineering resources to bloggers like you instead of to spammers. For more information, please see Blogger Help: http://help.blogger.com/bin/answer.py?answer=42577

Thank you for your understanding and for your help with our spam-fighting efforts.

Sincerely,

The Blogger Team"

Let's see if I can publish this. (Update: it looks like I can still publish, but have to interpret a captcha to show I'm probably human...)

Further update: how could Google's automatic spam blog detector be improved? Well, Google offers a lot of tools for reading blogs. Some fraction of my regular readers apparently read Market Design on Google Reader, since it reports 858 subscribers when I checked just now. (You can check too, or subscribe, by going to Google Reader and typing "market design" after clicking on the + box next to "add a subscription." You aren't committed at that point, but you can see the feed, and the number...)

So, a thought for the humans who program the automatic spam detector: check if spam blogs have fewer subscribers than real blogs, and, if so, include that in the next version of the algorithm.

Identifying desirable spouses

Empirical researchers who use matching models to study matching markets such as marriage are often faced with the difficulty that they can observe the results of the market--e.g. who marries whom--but not the intermediate choices that produced these matches (such as who courted whom, who proposed and was rejected, etc.). One approach is to look for particular markets in which such additional data can be found (as in these studies in India, the U.S., and Korea). Another is to develop statistical tools to infer the missing data, e.g. about the preferences of men and women, from the readily observable outcomes.

A NBER working paper that takes this latter approach is Identification in Matching Games, by Jeremy T. Fox - http://papers.nber.org/papers/W15092.

Here's the first paragraph from the introduction:
"Matching games are a new and important area of empirical interest. Consider the classic example of marriage. A researcher may have data on a set of marriages in each of a set of independent matching markets, say a set of towns. The researcher observes characteristics of each man and each woman in each town, as well as the sets of marriages that occurred. The researcher observes equilibrium outcomes, here marriages, and not choice sets, so identification in this type of model will not be able to rely trivially on the analysis of single-agent demand models. What type of parameters can be identified from these data?"

And here's the formal abstract:
Abstract: I study a many-to-many, two-sided, transferable-utility matching game. Consider data on matches or relationships between agents but not on the choice set of each agent. I investigate what economic parameters can be learned from data on equilibrium matches and agent characteristics. Features of a production function, which gives the surplus from a match, are nonparametrically identified. In particular, the ratios of complementarities from multiple pairs of inputs are identified. Also, the ordering of production levels is identified.

The market for bulk commodity shipments

The transport of bulk commodities by sea is a business that depends on matching loads to ships. When times are good, ships may be fully booked, and costly, and when times are bad ships may be available and cheap.

"The Baltic Exchange is an association of ship owners, and has a long and colorful history. Because shipping prices are an indicator of the general economy, the Baltic Exchange Dry Index, which measures the cost of hiring a big ship, is a leading indicator of commodities trading in particular and of economic activity in general.

As recently adjusted, the components of the index are indices for different kinds of shipping, in order of cargo capacity: Capesize (too big to transit the Suez canal, so have to go around), Panamax (the maximum size ship that can go through the Panama canal), Supramax, and Handysize.