When Marilda Sotomayor and I wrote our 1990 book on matching, we divided the book into models without money (like the marriage model) and models with money (like auction models), and showed how similar results obtained for both kinds of models. There's been lots of recent progress in unifying those models and understanding why the results were so similar. The most recent paper in this literature is by John Hatfield and Scott Kominers, Many-to-Many Matching with Contracts, and I asked them to write a blog post about it, which appears below.
"A few years ago, Hatfield and Milgrom (2005) introduced "(many-to-one) matching with contracts," a generalization of classical two-sided matching in which contracts between agents specify both (1) a matching and (2) conditions of the match (such as wages, hours, or specific responsibilities). The results of Hatfield and Milgrom (2005) are surprisingly general--although presented using matching-theoretic language, the Hatfield and Milgrom (2005) model encompasses not only two-sided matching but also several package auction models.Hatfield and Milgrom (2005) assumed a many-to-one matching market, that is, a market in which agents on one side of the market (the "doctors") were never allowed to sign more than one contract. Although reasonable for some applications of matching (such as school choice), some matching applications (such as the United Kingdom Medical Intern match) allow "many-to-many matching," in which every agent can be assigned to multiple agents on the other side of the market.In "Many-to-Many Matching with Contracts," we develop a theory of "many-to-many” version of matching with contracts which extends the model of Hatfield and Milgrom (2005) to allow all agents to accept multiple contracts.This framework extends contract matching to a host of applications not previously covered by generalized matching theory, including the United Kingdom Medical Intern match (discussed above), the United States National Resident Matching Program (which allows agents to pair together and match as "couples" who can receive two jobs), and the matching of consultants to firms. Additionally, many-to-many matching with contracts generalizes the theory of bilateral "buyer-seller markets".
We prove that substitutability of preferences (for agents on both sides of the market) is both sufficient and necessary to guarantee the existence of stable many-to-many contract allocations; in many-to-one applications, in contrast, weaker conditions than substitutability guarantee existence. This result shows that, in general, a stable match is not guaranteed to exist in the matching with couples problem, since couples' preferences are generally assumed to be non-substitutable by nature. These results also provide insight into why the necessity result does not hold in the many-to-one matching case, and allows us to identify a new class of non-substitutable many-to-one preferences which are in some sense projections of substitutable many-to-many preferences, and for which the existence of a stable match is guaranteed."
Wednesday, October 7, 2009
Tuesday, October 6, 2009
Market prediction and the Challenger disaster
Michael Trick has a post on Models, Information, and Market Rationality which shows a graph of the stock prices of Morton Thiokol, Lockheed, Martin Marietta, and Rockwell, in the hours after the Challenger disaster.
"The stock price for all of the companies immediately dropped 7-8% after the disaster. Within an hour, three companies went back up to being just 2-3% down, while one company further decreased: Morton Thiokol. The company responsible for the O-ring (of Richard Feynman and ice water fame): Morton Thiokol. It is certainly provocative that the market seemed to know something immediately that took an investigation months to determine. ...
But, as Bryan reminds me, this was not exactly a mystery to everyone at the time: the engineers involved strongly suspected early what the issue was and later fed that information to Feynman. So the information was out there and perhaps that information leaked out to the market in the immediate aftermath of the explosion. So perhaps it is not so mysterious after all. And there may well be other explanations for the larger drop off by Motton Thiokol."
"The stock price for all of the companies immediately dropped 7-8% after the disaster. Within an hour, three companies went back up to being just 2-3% down, while one company further decreased: Morton Thiokol. The company responsible for the O-ring (of Richard Feynman and ice water fame): Morton Thiokol. It is certainly provocative that the market seemed to know something immediately that took an investigation months to determine. ...
But, as Bryan reminds me, this was not exactly a mystery to everyone at the time: the engineers involved strongly suspected early what the issue was and later fed that information to Feynman. So the information was out there and perhaps that information leaked out to the market in the immediate aftermath of the explosion. So perhaps it is not so mysterious after all. And there may well be other explanations for the larger drop off by Motton Thiokol."
Prediction markets and Olympic cities
Over at MidasOracle.org the word is that Chicago won’t have the Olympics in 2016, despite the predictions of a number of well known prediction markets.
"The Chicago candidacy, which was favored by the prediction markets ...is the one that fared the worst."
"The prediction markets are not able to forecast which country will get the Olympics. The IOC is a close aristocratic group that does not leak information. Hence, it is not possible to aggregate information." (emphasis in original)
I guess President Obama also thought that Chicago had a good chance.
"The Chicago candidacy, which was favored by the prediction markets ...is the one that fared the worst."
"The prediction markets are not able to forecast which country will get the Olympics. The IOC is a close aristocratic group that does not leak information. Hence, it is not possible to aggregate information." (emphasis in original)
I guess President Obama also thought that Chicago had a good chance.
Monday, October 5, 2009
Incentives and food safety
In a disturbing story on food safety, the NY Times focuses on ground beef and reports E. Coli Path Shows Flaws in Ground Beef Inspection .
The problem has to do with both incentives and regulation. While companies have incentives to try to avoid selling contaminated food, it turns out there are incentives for not knowing where the contamination originated, and this makes it hard to eliminate. The problem is that most ground meat is a mix of meat scraps purchased from many providers.
"Meat companies and grocers have been barred from selling ground beef tainted by the virulent strain of E. coli known as O157:H7 since 1994, after an outbreak at Jack in the Box restaurants left four children dead. Yet tens of thousands of people are still sickened annually by this pathogen, federal health officials estimate, with hamburger being the biggest culprit. Ground beef has been blamed for 16 outbreaks in the last three years alone, including the one that left Ms. Smith paralyzed from the waist down. This summer, contamination led to the recall of beef from nearly 3,000 grocers in 41 states. "
...
"Ground beef is usually not simply a chunk of meat run through a grinder. Instead, records and interviews show, a single portion of hamburger meat is often an amalgam of various grades of meat from different parts of cows and even from different slaughterhouses. These cuts of meat are particularly vulnerable to E. coli contamination, food experts and officials say. Despite this, there is no federal requirement for grinders to test their ingredients for the pathogen. "
That is, food processors are required to test their final product, but not their ingredients.
"Those low-grade ingredients are cut from areas of the cow that are more likely to have had contact with feces, which carries E. coli, industry research shows. Yet Cargill, like most meat companies, relies on its suppliers to check for the bacteria and does its own testing only after the ingredients are ground together. The United States Department of Agriculture, which allows grinders to devise their own safety plans, has encouraged them to test ingredients first as a way of increasing the chance of finding contamination.
Unwritten agreements between some companies appear to stand in the way of ingredient testing. Many big slaughterhouses will sell only to grinders who agree not to test their shipments for E. coli, according to officials at two large grinding companies. Slaughterhouses fear that one grinder’s discovery of E. coli will set off a recall of ingredients they sold to others." (emphasis added)
...
"The retail giant Costco is one of the few big producers that tests trimmings for E. coli before grinding, a practice it adopted after a New York woman was sickened in 1998 by its hamburger meat, prompting a recall."
...
"But even Costco, with its huge buying power, said it had met resistance from some big slaughterhouses. “Tyson will not supply us,” Mr. Wilson said. “They don’t want us to test.” "
The problem has to do with both incentives and regulation. While companies have incentives to try to avoid selling contaminated food, it turns out there are incentives for not knowing where the contamination originated, and this makes it hard to eliminate. The problem is that most ground meat is a mix of meat scraps purchased from many providers.
"Meat companies and grocers have been barred from selling ground beef tainted by the virulent strain of E. coli known as O157:H7 since 1994, after an outbreak at Jack in the Box restaurants left four children dead. Yet tens of thousands of people are still sickened annually by this pathogen, federal health officials estimate, with hamburger being the biggest culprit. Ground beef has been blamed for 16 outbreaks in the last three years alone, including the one that left Ms. Smith paralyzed from the waist down. This summer, contamination led to the recall of beef from nearly 3,000 grocers in 41 states. "
...
"Ground beef is usually not simply a chunk of meat run through a grinder. Instead, records and interviews show, a single portion of hamburger meat is often an amalgam of various grades of meat from different parts of cows and even from different slaughterhouses. These cuts of meat are particularly vulnerable to E. coli contamination, food experts and officials say. Despite this, there is no federal requirement for grinders to test their ingredients for the pathogen. "
That is, food processors are required to test their final product, but not their ingredients.
"Those low-grade ingredients are cut from areas of the cow that are more likely to have had contact with feces, which carries E. coli, industry research shows. Yet Cargill, like most meat companies, relies on its suppliers to check for the bacteria and does its own testing only after the ingredients are ground together. The United States Department of Agriculture, which allows grinders to devise their own safety plans, has encouraged them to test ingredients first as a way of increasing the chance of finding contamination.
Unwritten agreements between some companies appear to stand in the way of ingredient testing. Many big slaughterhouses will sell only to grinders who agree not to test their shipments for E. coli, according to officials at two large grinding companies. Slaughterhouses fear that one grinder’s discovery of E. coli will set off a recall of ingredients they sold to others." (emphasis added)
...
"The retail giant Costco is one of the few big producers that tests trimmings for E. coli before grinding, a practice it adopted after a New York woman was sickened in 1998 by its hamburger meat, prompting a recall."
...
"But even Costco, with its huge buying power, said it had met resistance from some big slaughterhouses. “Tyson will not supply us,” Mr. Wilson said. “They don’t want us to test.” "
Sunday, October 4, 2009
Kidney sales
Here's a very interesting 9 minute YouTube video on kidney sales, including in the U.S.:CNN Reports On The Buying & Selling Of Human Organs - 10/03/09
It argues that (illegal) sales in the U.S. may still be rare, but not rare like unicorns.
HT to Chris. F. Masse, http://www.midasoracle.org/
It argues that (illegal) sales in the U.S. may still be rare, but not rare like unicorns.
HT to Chris. F. Masse, http://www.midasoracle.org/
Course allocation by Budish, updated
Eric Budish's updated (and still remarkable) paper is here:
The Combinatorial Assignment Problem: Approximate Competetive Equilibrium From Equal Incomes,
and Eric himself is now at Chicago's Booth School of Business.
Here is my previous post on the first version of that paper (which was Eric's jobmarket paper).
The Combinatorial Assignment Problem: Approximate Competetive Equilibrium From Equal Incomes,
and Eric himself is now at Chicago's Booth School of Business.
Here is my previous post on the first version of that paper (which was Eric's jobmarket paper).
Saturday, October 3, 2009
Hotbeds of innovation: food in Portland
Why are Silicon Valley and Cambridge MA hotbeds of innovation? A nice NY Times story about the culinary scene in Portland Maine, by Julia Moskin, might give some insights: In Portland’s Restaurants, a Down East Banquet .
"Portland’s many chefs and bakers, its turnip farmers and cookbook sellers and assorted mad food geniuses are gearing up for another lively winter.
“I wouldn’t call it a competition, I’d call it a collective,” Josh Potocki, the chef and owner of 158 Pickett St. Café in South Portland, said of the city’s food scene. “We are all trying to raise the level of food in Portland to insanely high.” ...
"Chefs here feed off one another’s work in a way that’s impossible in larger cities (Portland’s population is about 65,000, and it has a compact urban center), constantly eating in and commenting on one another’s restaurants. “I’ve made enemies, for sure,” said Joe Ricchio, a bartender who makes Vietnamese pho on his days off, has a weakness for flaming scorpion bowls, and writes a blog titled Portland Food Coma.
In 2007, Mr. Ricchio started a festively debauched event now known as Deathmatch, a kind of extended “Iron Chef” dinner, with each invited chef contributing a course. “Each one takes five years off your life,” Mr. Ricchio said."...
"Most of Portland’s young chefs ...have worked in — and walked out of — one another’s kitchens. ...Many have cycled through the twin temples of Sam Hayward’s Fore Street or Hugo’s on Middle Street, where Rob Evans is the chef. These are the kitchens that first defined Portland as a destination for rigorously local and regularly delicious food. "...
“Ninety percent of the best restaurants are chef-owned, small, single-operator places,” said Samantha Hoyt Lindgren, an owner of Rabelais, an all-food bookstore on Middle Street ...“That makes a huge difference in the quality of the food and the relationships with purveyors,” she said."..."And for chefs to become owners, the price of entry — key money, kitchen renovation, etc. — is relatively low. "
For related earlier posts, see Market for hand crafted food and Market for hand crafted food, continued
"Portland’s many chefs and bakers, its turnip farmers and cookbook sellers and assorted mad food geniuses are gearing up for another lively winter.
“I wouldn’t call it a competition, I’d call it a collective,” Josh Potocki, the chef and owner of 158 Pickett St. Café in South Portland, said of the city’s food scene. “We are all trying to raise the level of food in Portland to insanely high.” ...
"Chefs here feed off one another’s work in a way that’s impossible in larger cities (Portland’s population is about 65,000, and it has a compact urban center), constantly eating in and commenting on one another’s restaurants. “I’ve made enemies, for sure,” said Joe Ricchio, a bartender who makes Vietnamese pho on his days off, has a weakness for flaming scorpion bowls, and writes a blog titled Portland Food Coma.
In 2007, Mr. Ricchio started a festively debauched event now known as Deathmatch, a kind of extended “Iron Chef” dinner, with each invited chef contributing a course. “Each one takes five years off your life,” Mr. Ricchio said."...
"Most of Portland’s young chefs ...have worked in — and walked out of — one another’s kitchens. ...Many have cycled through the twin temples of Sam Hayward’s Fore Street or Hugo’s on Middle Street, where Rob Evans is the chef. These are the kitchens that first defined Portland as a destination for rigorously local and regularly delicious food. "...
“Ninety percent of the best restaurants are chef-owned, small, single-operator places,” said Samantha Hoyt Lindgren, an owner of Rabelais, an all-food bookstore on Middle Street ...“That makes a huge difference in the quality of the food and the relationships with purveyors,” she said."..."And for chefs to become owners, the price of entry — key money, kitchen renovation, etc. — is relatively low. "
For related earlier posts, see Market for hand crafted food and Market for hand crafted food, continued
Friday, October 2, 2009
Klemperer's auction design for toxic assets
Over at voxeu.org, Paul Klemperer writes about Central bank liquidity and “toxic asset” auctions, which describes briefly his paper
Klemperer, Paul (2009). “The Product-Mix Auction: A New Auction Design for Differentiated Goods”.
In his Voxeu post he says "The product-mix auction yields better “matching” between suppliers and demanders, reduced market power, greater volume and liquidity, and therefore also improved efficiency, revenue, and quality of information than feasible alternatives. Its potential applications therefore extend well beyond the financial context."
Klemperer, Paul (2009). “The Product-Mix Auction: A New Auction Design for Differentiated Goods”.
In his Voxeu post he says "The product-mix auction yields better “matching” between suppliers and demanders, reduced market power, greater volume and liquidity, and therefore also improved efficiency, revenue, and quality of information than feasible alternatives. Its potential applications therefore extend well beyond the financial context."
Thursday, October 1, 2009
Michael Kearns heads up a new market design program at Penn
The University of Pennsylvania today issued a press release announcing a new undergrad program: Penn Launches Undergraduate Program in Market and Social Systems Engineering, Nation’s First.
"PHILADELPHIA -- The University of Pennsylvania has launched a first-of-its-kind program that will prepare undergraduate students to shape the technologies that underpin Web search, keyword auctions, electronic commerce, social and financial networks and the novel and unanticipated markets and social systems of the years ahead. "
...
"“Traditional programs don’t prepare students to design systems that take into account the goals and incentives of the people who use them,” said Michael Kearns, professor in the Department of Computer and Information Science in Penn’s School of Engineering and Applied Science and the program’s founding faculty director. “We haven’t asked engineering students to take a course in game theory to understand how incentives work or in sociology to understand human behavior. There is now enough science out there on the intersection of these topics to design undergraduate courses.”
In 2003, Kearns developed a Penn course, Networked Life, which engages students in hands-on explorations of the networks in which they participate every day. Now one of the most popular courses at the University, Networked Life also served as a proving ground for the larger MKSE program of which it will become a part.
Kearns is the National Center Professor of Computer and Information Science in Penn Engineering, with secondary appointments in Statistics and Operations and Information Management at The Wharton School. "
"PHILADELPHIA -- The University of Pennsylvania has launched a first-of-its-kind program that will prepare undergraduate students to shape the technologies that underpin Web search, keyword auctions, electronic commerce, social and financial networks and the novel and unanticipated markets and social systems of the years ahead. "
...
"“Traditional programs don’t prepare students to design systems that take into account the goals and incentives of the people who use them,” said Michael Kearns, professor in the Department of Computer and Information Science in Penn’s School of Engineering and Applied Science and the program’s founding faculty director. “We haven’t asked engineering students to take a course in game theory to understand how incentives work or in sociology to understand human behavior. There is now enough science out there on the intersection of these topics to design undergraduate courses.”
In 2003, Kearns developed a Penn course, Networked Life, which engages students in hands-on explorations of the networks in which they participate every day. Now one of the most popular courses at the University, Networked Life also served as a proving ground for the larger MKSE program of which it will become a part.
Kearns is the National Center Professor of Computer and Information Science in Penn Engineering, with secondary appointments in Statistics and Operations and Information Management at The Wharton School. "
Further unraveling of basketball recruiting
Zhenyu Lai, a graduate student in Economics at Harvard, who is taking Market Design this semester, sent me the following email, which he gave me permission to reproduce below.
After last friday's class discussion on unravelling in markets, I came across this article about unravelling in NCAA basketball with a ton of good quotes and anecdotes.
What is particularly interesting is about the role played by agents. Increasingly, agents try to form relationships with potential NBA players early on in their college careers. And they're not just targeting the surefire stars, but gambling on marginal prospects.
Interesting excerpts:
1. Technological improvements aid unravelling markets. Agents are using facebook to make contact with players early.
2. Official rules are abused. Similar to the market example on clinical psychologists, looking at the NCAA rules for agent recruiting is very indicative of the unraveling problem. "Agents are free to contact players in high school or in college through social networking sites, on the phone or in person. As long as there is no written agreement or money exchanged, an agent or a representative of an agent can form a relationship with a player, his family and/or his handlers." An agent is quoted, "It's not breaking the rules. You're just building a relationship with a potential client down the road.". The columnist describes this as "the new normal in amateur basketball."
3. Coaches are in on it too. Much like the market for law clerks, agents (aka judges) develop relationship with coaches (aka law school deans) to ensure that they are making "a sound investment" on their prospect. However, coaches are getting ticked off. The "right way" to do this is apparently for the agents to approach the coach and the player's parents first, not to directly add the player on facebook, where the player may then bypass the coach completely.
4. Agent's argument for unravelling. "Domantay's argument for an agent's trying to make inroads in a profession dominated by an elite few is that if he were to wait until a college player's senior year, he becomes just another name on the list."
5. Argument that unraveling is bad. "If an agent contacts a kid directly, then there should be repercussions. Guys get in with kids and prey on the youthfulness and financial backgrounds and offer things to lock them in and set up a potential for blackmail: If I gave you this, then you owe me." Agents are using runners to form relationships with kids early and leveraging on family contacts and relationships. There is an aura of suspicion where high school kids are wary of who to trust.
6. Agent's motivation for promoting unraveling. "Whoever can control the kid can control the revenue stream -- [maybe] it's a kid going to college benefiting the college coach and leading to a better job. the player dictates the revenue. Everybody is trying to get in sooner and sooner however they can."
Interestingly, the columnist ends off with this quote which is filled with a tone of finality that unraveling is inevitable and an enduring legacy of capitalism,
"The pool of talent, with leagues all over the globe to fill and money to be made, means that anybody with potential is in play to be courted, and so too are their families, their friends, and their AAU and high school coaches. That's the new reality for college coaches. And there's no reason to think it will ever change back."
My thoughts on unraveling in college basketball:
1. High school students are usually at an impressionable age and easily influenced by people close to them, prompting this 'unraveling' process of agents trying to get close to them. While high school students might not be expected to make savvy long-term agent decisions, more needs to be done to make the agent seem like the "bad guy" for approaching the student early. No binding contract is allowed, and kids are empowered to change agents anytime. However, especially if the agent has some influence on a family member (or is a family member..), severing an agent relationship might be tricky. To discourage unraveling, there needs to be lower barriers to changing agents.
2. The NCAA doesn't have jurisdiction over agents (like in the case of federal judges), but some states do where a law states that there can be "significant damage resulting from the impermissible and often times illegal practices of some athlete agents. Violations of NCAA agent legislation impact the eligibility of student-athletes for further participation in NCAA competition". This law is passed in 38 states. However, this law affects the athletes and not the agents. One remedy would be for the NBA to revoke the right of agents to represent their clients if a recruiting violation is found. Agent's licenses could be subject to yearly review. Entry into the agent profession could be tightly regulated.
3. Perhaps NBA draftees could attend an "agent convention" where they could interview various representatives and have the right to choose from among them without any pressure. If it were a standard practice to be connected with legitimate agents only after you enter the NBA, players would then in no way be obliged to sign with an agent early even if they were to have already accepted illegal gifts.
After last friday's class discussion on unravelling in markets, I came across this article about unravelling in NCAA basketball with a ton of good quotes and anecdotes.
What is particularly interesting is about the role played by agents. Increasingly, agents try to form relationships with potential NBA players early on in their college careers. And they're not just targeting the surefire stars, but gambling on marginal prospects.
Interesting excerpts:
1. Technological improvements aid unravelling markets. Agents are using facebook to make contact with players early.
2. Official rules are abused. Similar to the market example on clinical psychologists, looking at the NCAA rules for agent recruiting is very indicative of the unraveling problem. "Agents are free to contact players in high school or in college through social networking sites, on the phone or in person. As long as there is no written agreement or money exchanged, an agent or a representative of an agent can form a relationship with a player, his family and/or his handlers." An agent is quoted, "It's not breaking the rules. You're just building a relationship with a potential client down the road.". The columnist describes this as "the new normal in amateur basketball."
3. Coaches are in on it too. Much like the market for law clerks, agents (aka judges) develop relationship with coaches (aka law school deans) to ensure that they are making "a sound investment" on their prospect. However, coaches are getting ticked off. The "right way" to do this is apparently for the agents to approach the coach and the player's parents first, not to directly add the player on facebook, where the player may then bypass the coach completely.
4. Agent's argument for unravelling. "Domantay's argument for an agent's trying to make inroads in a profession dominated by an elite few is that if he were to wait until a college player's senior year, he becomes just another name on the list."
5. Argument that unraveling is bad. "If an agent contacts a kid directly, then there should be repercussions. Guys get in with kids and prey on the youthfulness and financial backgrounds and offer things to lock them in and set up a potential for blackmail: If I gave you this, then you owe me." Agents are using runners to form relationships with kids early and leveraging on family contacts and relationships. There is an aura of suspicion where high school kids are wary of who to trust.
6. Agent's motivation for promoting unraveling. "Whoever can control the kid can control the revenue stream -- [maybe] it's a kid going to college benefiting the college coach and leading to a better job. the player dictates the revenue. Everybody is trying to get in sooner and sooner however they can."
Interestingly, the columnist ends off with this quote which is filled with a tone of finality that unraveling is inevitable and an enduring legacy of capitalism,
"The pool of talent, with leagues all over the globe to fill and money to be made, means that anybody with potential is in play to be courted, and so too are their families, their friends, and their AAU and high school coaches. That's the new reality for college coaches. And there's no reason to think it will ever change back."
My thoughts on unraveling in college basketball:
1. High school students are usually at an impressionable age and easily influenced by people close to them, prompting this 'unraveling' process of agents trying to get close to them. While high school students might not be expected to make savvy long-term agent decisions, more needs to be done to make the agent seem like the "bad guy" for approaching the student early. No binding contract is allowed, and kids are empowered to change agents anytime. However, especially if the agent has some influence on a family member (or is a family member..), severing an agent relationship might be tricky. To discourage unraveling, there needs to be lower barriers to changing agents.
2. The NCAA doesn't have jurisdiction over agents (like in the case of federal judges), but some states do where a law states that there can be "significant damage resulting from the impermissible and often times illegal practices of some athlete agents. Violations of NCAA agent legislation impact the eligibility of student-athletes for further participation in NCAA competition". This law is passed in 38 states. However, this law affects the athletes and not the agents. One remedy would be for the NBA to revoke the right of agents to represent their clients if a recruiting violation is found. Agent's licenses could be subject to yearly review. Entry into the agent profession could be tightly regulated.
3. Perhaps NBA draftees could attend an "agent convention" where they could interview various representatives and have the right to choose from among them without any pressure. If it were a standard practice to be connected with legitimate agents only after you enter the NBA, players would then in no way be obliged to sign with an agent early even if they were to have already accepted illegal gifts.
Further consequences of unraveling of law firm hiring
The Crimson reports on the difficulties facing Harvard Law students graduating in this recession year: Tough Times For Harvard Lawyers
"The two-year lag between when firms extend job offers and when employees begin their first year forces firms to predict associate demand far in advance of the start date and leads to inaccurate predictions of hiring needs. According to Weber, the backlog of entry-level associates or “overhang” is negatively impacting firm demand for associates in this recruiting cycle. After the financial crisis pummelled investment banks and the fountain of transactional work dried up, law firms were forced to keep the commitments they made to new hires two years earlier. The result: a spate of deferred start dates that began with the class of 2009 and may continue with the class of 2010. "
"The two-year lag between when firms extend job offers and when employees begin their first year forces firms to predict associate demand far in advance of the start date and leads to inaccurate predictions of hiring needs. According to Weber, the backlog of entry-level associates or “overhang” is negatively impacting firm demand for associates in this recruiting cycle. After the financial crisis pummelled investment banks and the fountain of transactional work dried up, law firms were forced to keep the commitments they made to new hires two years earlier. The result: a spate of deferred start dates that began with the class of 2009 and may continue with the class of 2010. "
Wednesday, September 30, 2009
A proliferation of penny auctions
Last year I thought about blogging about Swoopo, the "entertainment shopping" site that is run as an "all pay" auction for consumer goods, in which all bidders must pay to bid, but only the winning bidder receives the object. But soon enough there were excellent posts on the subject by others. I particularly like Ian Ayers at Freakonomics, who explained how Swoopo is similar to the "escalation auction" proposed years ago by Martin Shubik, which has become a staple demonstration in game theory classes, and Tyler Cowen at MR, who observes that Swoopo auctions can make a lot of money for the owners of the site, while most of the bidders lose. He writes "In short, swoopo is about as close to pure, distilled evil in a business plan as I've ever seen. " (emphasis in original). And here's the Wikipedia entry.
Swoopo bidders are a bit of a puzzle of the behavioral economics kind: are they like buyers of lottery tickets, who know that they will likely lose but find entertainment value by purchasing the right to dream (see this paper by Emily Oster)? Or are they making mistakes? And if the latter, will demand for this kind of auction dry up? Or will new suckers keep appearing?
But there are other, market level questions we can ask, and I got the beginning of an answer when I did a google search on "swoopo", or another search on "penny auction" . You'll find two things if you click on those searches: there are now a lot of similar auction sites, and there are also plenty of people who are eager to sell you software to set up your own "penny auction," as these sites have come to be known.
(BidRodeo's icon is a man on a bucking bronco, over the motto "Hold on the longest and win!")
What are the questions to which those observations are the beginnings of answers? I guess one is, "is it easy to earn outsized rents by selling to the gullible?". I presume most of the new sites make very little money. Whether they also attract away swoopo's customers or otherwise reduce swoopo's rents remains to be seen.
A new (job market) paper by Edward Augenblick at Stanford suggests that the already-established penny auctions may not disappear in the blink of an eye: Pay-As-You-Go: Theoretical and Empirical Analysis of a New Auction Format
He finds Swoopo to be quite profitable, and the abstract concludes:
"Finally, I attempt to address the long-term prospects of the market for these auctions. Using high frequency auction supply and user data, I estimate the current and optimal supply of auctions for a given number of users. This analysis suggests that the structure of the auction creates barriers to quickly developing a large userbase, allowing the most-established competitor to continue making large profits in the medium-term. This analysis is supported by auction-level data from five competitors. "
HT Eduardo Azevedo and Muriel Niederle
Swoopo bidders are a bit of a puzzle of the behavioral economics kind: are they like buyers of lottery tickets, who know that they will likely lose but find entertainment value by purchasing the right to dream (see this paper by Emily Oster)? Or are they making mistakes? And if the latter, will demand for this kind of auction dry up? Or will new suckers keep appearing?
But there are other, market level questions we can ask, and I got the beginning of an answer when I did a google search on "swoopo", or another search on "penny auction" . You'll find two things if you click on those searches: there are now a lot of similar auction sites, and there are also plenty of people who are eager to sell you software to set up your own "penny auction," as these sites have come to be known.
(BidRodeo's icon is a man on a bucking bronco, over the motto "Hold on the longest and win!")
What are the questions to which those observations are the beginnings of answers? I guess one is, "is it easy to earn outsized rents by selling to the gullible?". I presume most of the new sites make very little money. Whether they also attract away swoopo's customers or otherwise reduce swoopo's rents remains to be seen.
A new (job market) paper by Edward Augenblick at Stanford suggests that the already-established penny auctions may not disappear in the blink of an eye: Pay-As-You-Go: Theoretical and Empirical Analysis of a New Auction Format
He finds Swoopo to be quite profitable, and the abstract concludes:
"Finally, I attempt to address the long-term prospects of the market for these auctions. Using high frequency auction supply and user data, I estimate the current and optimal supply of auctions for a given number of users. This analysis suggests that the structure of the auction creates barriers to quickly developing a large userbase, allowing the most-established competitor to continue making large profits in the medium-term. This analysis is supported by auction-level data from five competitors. "
HT Eduardo Azevedo and Muriel Niederle
Tuesday, September 29, 2009
When a protected transaction meets a repugnant one: The MA suit over the Defense of Marriage Act
Same sex marriage raises issues involving both repugnant transactions and protected transactions. On the one hand, marriage is one of our most protected transactions: we reserve many rights for married couples, and a good deal of law and political rhetoric concerns marriage. But many people find marriage between anyone other than one man and one woman repugnant.
Nowhere is this clearer than in the lawsuits being pressed by the Commonwealth of Massachusetts (which was the first U.S. state to recognize same sex marriage) and other parties against the United States, in an attempt to roll back the federal Defense of Marriage Act.
At issue are the rights of married couples. Specifically (because marriage is a protected transaction), spouses are entitled to tax and other benefits. But (because some people find same sex marriage repugnant) the federal law denies same sex spouses married in Massachusetts federal benefits for married couples.
"Because of the law, the plaintiffs said, they were excluded from using federal benefits that opposite-sex couples can obtain, including health insurance programs for federal employees, retirement and survivor benefits under the Social Security Act, and the ability to file joint federal income tax returns."
That quote is from a story ( US lawyers defend letter of gay marriage ban) that emphasizes how this suit puts lawyers in the Obama administration Justice Department in the unusual position of defending the legality of a law that the administration would in fact like to see repealed.
"Government attorneys said in a brief filed yesterday in US District Court that the administration believes the federal Defense of Marriage Act, which bars the federal government from recognizing same-sex marriages, is discriminatory and wants it repealed.
“Consistent with the rule of law, however, the Department of Justice has long followed the practice of defending federal statutes as long as reasonable arguments can be made in support of their constitutionality, even if the department disagrees with a particular statute as a policy matter, as it does here,’’ the attorneys said."
(The MA suit is formally called Commonwealth of Massachusetts v. United States Department of Health and Human Services et al, and an associated suit is Gill et al. v. Office of Personnel Management, and here is the formal complaint, brought by GLAD, the Gay & Lesbian Advocates & Defenders.)
Nowhere is this clearer than in the lawsuits being pressed by the Commonwealth of Massachusetts (which was the first U.S. state to recognize same sex marriage) and other parties against the United States, in an attempt to roll back the federal Defense of Marriage Act.
At issue are the rights of married couples. Specifically (because marriage is a protected transaction), spouses are entitled to tax and other benefits. But (because some people find same sex marriage repugnant) the federal law denies same sex spouses married in Massachusetts federal benefits for married couples.
"Because of the law, the plaintiffs said, they were excluded from using federal benefits that opposite-sex couples can obtain, including health insurance programs for federal employees, retirement and survivor benefits under the Social Security Act, and the ability to file joint federal income tax returns."
That quote is from a story ( US lawyers defend letter of gay marriage ban) that emphasizes how this suit puts lawyers in the Obama administration Justice Department in the unusual position of defending the legality of a law that the administration would in fact like to see repealed.
"Government attorneys said in a brief filed yesterday in US District Court that the administration believes the federal Defense of Marriage Act, which bars the federal government from recognizing same-sex marriages, is discriminatory and wants it repealed.
“Consistent with the rule of law, however, the Department of Justice has long followed the practice of defending federal statutes as long as reasonable arguments can be made in support of their constitutionality, even if the department disagrees with a particular statute as a policy matter, as it does here,’’ the attorneys said."
(The MA suit is formally called Commonwealth of Massachusetts v. United States Department of Health and Human Services et al, and an associated suit is Gill et al. v. Office of Personnel Management, and here is the formal complaint, brought by GLAD, the Gay & Lesbian Advocates & Defenders.)
Monday, September 28, 2009
Reserving spaces in crowded places
It may be possible for vacationing Germans to reserve rental lounge chairs at a crowded beach or pool, but in Saudi Arabia it's a crime to reserve rental prayer mats, the Saudi Gazette reports: 2 held for renting Haram prayer space. It appears that both the reserving and the renting are repugnant.
"MAKKAH – Two persons have been arrested for reserving prayer spaces and renting them out to worshippers at Isha and Taraweeh prayer times...“The practice has diminished a lot this year,” Al-Wabil said. “However, we will show no lenience to anyone caught.”All persons who have been arrested for renting out prayer spaces have been foreigners, Al-Wabil said, adding that culprits are identified through a period of surveillance of individual carpets and persons claiming them beginning half an hour before the start of prayers.Sheikh Saleh Bin Fawzan Al-Fawzan of the Board of Senior Ulema and the Permanent Committee for Ifta ruled last week that reserving prayer spaces at the Grand Mosque in Makkah or the Prophet’s Mosque in Madina was “haraam”, or forbidden.“It is forbidden to reserve places in the mosques, unless the person has left for urgent reasons and intends to return soon, as otherwise it is tantamount to taking something by force,” Al-Fawzan told Okaz newspaper on Thursday. “It is also forbidden to rent a reserved place, and the authorities should put a stop to this vice (munkar).”
HT: Anouar El Haji at U. Amsterdam
"MAKKAH – Two persons have been arrested for reserving prayer spaces and renting them out to worshippers at Isha and Taraweeh prayer times...“The practice has diminished a lot this year,” Al-Wabil said. “However, we will show no lenience to anyone caught.”All persons who have been arrested for renting out prayer spaces have been foreigners, Al-Wabil said, adding that culprits are identified through a period of surveillance of individual carpets and persons claiming them beginning half an hour before the start of prayers.Sheikh Saleh Bin Fawzan Al-Fawzan of the Board of Senior Ulema and the Permanent Committee for Ifta ruled last week that reserving prayer spaces at the Grand Mosque in Makkah or the Prophet’s Mosque in Madina was “haraam”, or forbidden.“It is forbidden to reserve places in the mosques, unless the person has left for urgent reasons and intends to return soon, as otherwise it is tantamount to taking something by force,” Al-Fawzan told Okaz newspaper on Thursday. “It is also forbidden to rent a reserved place, and the authorities should put a stop to this vice (munkar).”
HT: Anouar El Haji at U. Amsterdam
Sunday, September 27, 2009
Are names destiny?
Does your name influence your choice of career? The following paragraph caught my eye, from a NY Times story on testing the safety of motorcycle helmets.
"Hugh H. Hurt, a researcher who developed the Head Protection Research Laboratory at the University of Southern California, and author of the Hurt Report, a seminal study of motorcycle crashes, calls the current Snell M2005 standard “a little bit excessive.” "
"Hugh H. Hurt, a researcher who developed the Head Protection Research Laboratory at the University of Southern California, and author of the Hurt Report, a seminal study of motorcycle crashes, calls the current Snell M2005 standard “a little bit excessive.” "
Thaler on mandated choice
In the NY Times, Dick Thaler considers how the way people are asked whether they would like to be deceased organ donors might influence the donation rate: Opting in vs. Opting Out .
Thaler thinks organ sales are too widely viewed as repugnant to be politically feasible. And despite the headline, he comes out in favor not of opt in or opt out as defaults, but rather mandated choice, a nudge of the kind he and Cass Sunstein celebrate in their best selling book of that name.
Thaler thinks organ sales are too widely viewed as repugnant to be politically feasible. And despite the headline, he comes out in favor not of opt in or opt out as defaults, but rather mandated choice, a nudge of the kind he and Cass Sunstein celebrate in their best selling book of that name.
"Here is how it works: When you go to renew your driver’s license and update your photograph, you are required to answer this question: “Do you wish to be an organ donor?” The state now has a 60 percent donor signup rate, according to Donate Life Illinois, a coalition of agencies. That is much higher than the national rate of 38 percent reported by Donate Life America
The Illinois system has another advantage. There can be legal conflicts over whether registering intent is enough to qualify you as an organ donor or whether a doctor must still ask your family’s permission. In France, for example, although there is technically a presumed-consent law, in practice doctors still seek relatives’ approval. In Illinois, the First-Person Consent Law, which created this system, makes one’s wishes to be a donor legally binding. Thus, mandated choice may achieve a higher rate of donations than presumed consent, and avoid upsetting those who object to presumed consent for whatever reasons. This is a winning combination.
THE key, however, is to make signup easy, and requiring people to make a choice is just one way to accomplish it. The private sector could help create other simple methods. Here is a challenge to Mr. Jobs: Why not create a Web site — and a free app for the iPhone — that lets people sign up as organ donors in their home states? "
The Illinois system has another advantage. There can be legal conflicts over whether registering intent is enough to qualify you as an organ donor or whether a doctor must still ask your family’s permission. In France, for example, although there is technically a presumed-consent law, in practice doctors still seek relatives’ approval. In Illinois, the First-Person Consent Law, which created this system, makes one’s wishes to be a donor legally binding. Thus, mandated choice may achieve a higher rate of donations than presumed consent, and avoid upsetting those who object to presumed consent for whatever reasons. This is a winning combination.
THE key, however, is to make signup easy, and requiring people to make a choice is just one way to accomplish it. The private sector could help create other simple methods. Here is a challenge to Mr. Jobs: Why not create a Web site — and a free app for the iPhone — that lets people sign up as organ donors in their home states? "
(Note from my earlier post on Steve Jobs' liver transplant that Massachusetts is one of the few states that allows you to sign up to be a donor online, and see also Thaler's remarks at the bottom of this other earlier post.)
One of the things I like about signing up online is that it allows people to think about organ donation at places other than the Department of Motor Vehicles. I wonder if that's the only place we should be asking people about donation; or whether that location invites you to think too much about fatal car crashes (which are far from the only way to become an organ donor, and which you might prefer not to think about).
On the DMV form at the top of the page you can see that here in Massachusetts we have "opt in" for organ donation, but mandated choice for voter registration. (You can enlarge the photo by clicking on it, if you're reading this on a small screen.) So Thaler's good suggestion would be easy to implement, a very gentle nudge in the right direction.
London Times reports on ads to sell kidneys
Despite the headlines, it isn't clear that they found any actual cash-for-kidney transactions, or the infrastructure to support them, but the willingness is there: Cash-strapped sell their kidneys to pay off debts.
"British victims of the credit crunch are offering to sell their kidneys for £25,000 or more to help pay debts, an investigation by The Sunday Times has revealed.
At least a dozen adverts have appeared on the internet offering kidneys for sale from British “donors”. Five of the sellers corresponded with undercover journalists, who posed as friends and relatives of sick patients to negotiate sales."
...
"Both men said they wanted to help those in need of kidney transplants at the same time as relieving their financial difficulties. A leading doctor said the phenomenon highlighted the need for a public discussion of the issue of selling organs.
Professor Peter Friend, a former president of the British Transplant Society, said: “The West has outlawed it for all sorts of good reasons, but the result is it goes underground. It is really important to have a debate.” Nearly 7,000 people in the UK are waiting for kidney transplants and 300 died last year while on the waiting list.
Offering to sell an organ in England, Wales and Northern Ireland is an offence under the Human Tissue Act even if the seller is planning to travel to another country for the transplant operation. "
"British victims of the credit crunch are offering to sell their kidneys for £25,000 or more to help pay debts, an investigation by The Sunday Times has revealed.
At least a dozen adverts have appeared on the internet offering kidneys for sale from British “donors”. Five of the sellers corresponded with undercover journalists, who posed as friends and relatives of sick patients to negotiate sales."
...
"Both men said they wanted to help those in need of kidney transplants at the same time as relieving their financial difficulties. A leading doctor said the phenomenon highlighted the need for a public discussion of the issue of selling organs.
Professor Peter Friend, a former president of the British Transplant Society, said: “The West has outlawed it for all sorts of good reasons, but the result is it goes underground. It is really important to have a debate.” Nearly 7,000 people in the UK are waiting for kidney transplants and 300 died last year while on the waiting list.
Offering to sell an organ in England, Wales and Northern Ireland is an offence under the Human Tissue Act even if the seller is planning to travel to another country for the transplant operation. "
Saturday, September 26, 2009
Where burial societies go to die
The NY Times has a story on burial societies, cooperatives set up by immigrants in the 1800s and early 1900s to buy and maintain cemeteries. Membership came with burial rights. But the members of the remaining burial societies are aging, and as the society administrators die, it is hard to find replacements: With Demise of Jewish Burial Societies, Resting Places Are in Turmoil .
Various public agencies have gotten involved, e.g. in NY, the New York State Division of Cemeteries exercises general supervision over cemeteries, while the New York State Insurance Department supervises insurance companies. A burial society is both. The Insurance Department's Liquidation Bureau protects consumers who hold policies with failed insurance companies, and its office of Miscellaneous Estates has taken over the administration of some of the burial societies, until their last members are buried.
"Mark G. Peters, who heads the quasi-public Liquidation Bureau...said the government viewed burial societies as a type of insurer. “They may be a historically anachronistic insurance product,” he said, “but we are essentially the only safety net for people still depending on these societies.” "
At a time when the appropriate role of regulators for a variety of markets, including insurance markets, is under new scrutiny, it's reassuring to hear of a fairly unobtrusive regulator stepping up to do the job for which it was designed.
Various public agencies have gotten involved, e.g. in NY, the New York State Division of Cemeteries exercises general supervision over cemeteries, while the New York State Insurance Department supervises insurance companies. A burial society is both. The Insurance Department's Liquidation Bureau protects consumers who hold policies with failed insurance companies, and its office of Miscellaneous Estates has taken over the administration of some of the burial societies, until their last members are buried.
"Mark G. Peters, who heads the quasi-public Liquidation Bureau...said the government viewed burial societies as a type of insurer. “They may be a historically anachronistic insurance product,” he said, “but we are essentially the only safety net for people still depending on these societies.” "
At a time when the appropriate role of regulators for a variety of markets, including insurance markets, is under new scrutiny, it's reassuring to hear of a fairly unobtrusive regulator stepping up to do the job for which it was designed.
Friday, September 25, 2009
Common deadlines
One way to try to control unraveling of transaction dates is to specify, and try to enforce, particular times at which certain aspects of a market are allowed to unfold. Some examples:
National Letter of Intent for college athletic recruits: A Quick Reference Guide to the NLI
My favorite is the April 15 resolution by the Council of Graduate Schools, signed by most universities, which is carefully designed to be fairly self-enforcing:
"Students are under no obligation to respond to offers of financial support prior to April 15; earlier deadlines for acceptance of such offers violate the intent of this Resolution. In those instances in which a student accepts an offer before April 15, and subsequently desires to withdraw that acceptance, the student may submit in writing a resignation of the appointment at any time through April 15. ... It is further agreed by the institutions and organizations subscribing to the above Resolution that a copy of this Resolution should accompany every scholarship, fellowship, traineeship, and assistantship offer."
Note that the incentive to violate the agreement by insisting that applicants respond before April 15 is undercut by the fact that the resolution allows students to accept such offers, and then subsequently reject them if they get a better offer. That is, the resolution effectively de-fuses Exploding offers by making them non-binding.
National Letter of Intent for college athletic recruits: A Quick Reference Guide to the NLI
NALP Principles and Standards for hiring by law firms: PART V: GENERAL STANDARDS FOR THE TIMING OF OFFERS AND DECISIONS "Employers offering full-time positions to commence following graduation to candidates not previously employed by them should leave those offers open for at least 45 days following the date of the offer letter or until December 30, whichever comes first. Offers made after December 15 for full-time positions to commence following graduation should remain open for at least two weeks after the date of the offer letter. "
It turns out that this provision needs some enforcement in a recession. The AmLaw Daily reports: S&C vs. Harvard and the Relevance of NALP's 45-Day Rule
"Perhaps nothing epitomizes the anxiety of this recruiting season better than Sullivan & Cromwell's abandoned attempt to bypass a standard, set by NALP, that firms leave offers to students open for up to 45 days. In late July, S&C called several of the nation's top law schools and informed career services personnel at those schools that the firm would not be following the 45-day guideline, according to six sources with direct knowledge of the situation. All six spoke only on the condition that they not be identified publicly. Instead, S&C told the career services personnel, the firm would require prospects to respond yes or no in two weeks."... "S&C backed down quickly and promised to obey the 45-day standard, according to all six sources who spoke to us about the matter. But that doesn't mean the 45-day guideline is set in stone. James Leipold, executive director at NALP, says several firms (none of which he would name) have called the organization asking if they could skip the 45-day rule in some way this season. Several have asked for permission to keep offers open for 45 days or until they collect as many acceptances as they want--whichever comes first. "
My favorite is the April 15 resolution by the Council of Graduate Schools, signed by most universities, which is carefully designed to be fairly self-enforcing:
"Students are under no obligation to respond to offers of financial support prior to April 15; earlier deadlines for acceptance of such offers violate the intent of this Resolution. In those instances in which a student accepts an offer before April 15, and subsequently desires to withdraw that acceptance, the student may submit in writing a resignation of the appointment at any time through April 15. ... It is further agreed by the institutions and organizations subscribing to the above Resolution that a copy of this Resolution should accompany every scholarship, fellowship, traineeship, and assistantship offer."
Note that the incentive to violate the agreement by insisting that applicants respond before April 15 is undercut by the fact that the resolution allows students to accept such offers, and then subsequently reject them if they get a better offer. That is, the resolution effectively de-fuses Exploding offers by making them non-binding.
Thursday, September 24, 2009
Entrepreneurial Market Design
In the coming weeks, I'll be making a series of posts on a subject I term Entrepreneurial Market Design, the study of creating for-profit marketplaces. Such marketplaces often require innovations (market rules, information flows, timing adjustments, reputation mechanisms) to resolve longstanding inefficiencies (lack of market thickness, adverse selection, high transaction costs, etc). These innovations can create significant value for market participants, and at the same time offer a promising business model for the entrepreneur.
I've had the opportunity to study many such markets, in the capacity of academic researcher, case author, and advisor to students who are have started market-based businesses. The first set of markets I'll list are those founded or managed by recent HBS students with whom I've interacted. Future posts will go into greater detail on these.
TeachStreet. TeachStreet is a platform for matching students with classes, usually in a non-academic setting. Instructors of classes ranging from foreign language to cooking to SAT prep to belly dancing post listings on TeachStreet.com. Users browse through classes and sign up, and Teachstreet takes a commission for each new student. Julie Sandler, a current HBS student, is currently investigating how to expand to the platform to include children's classes. www.teachstreet.com
RelayRides. Concisely described as a peer-to-peer version of Zipcar. Car owners sign up to make their cars available for rental, naming their own rates and hours. Renters select from available cars. In theory, prices could be lower than in Zipcar and fleet size could be much larger. This looks like a classic two-sided network, but with some intriguing challenges of insurance, monitoring, and adverse selection. The founders are HBS students Shelby Clark and Nabeel Al-Kady. http://www.relayrides.com/check-zip.cgi?zip=21202&x=10&y=16
ClearMechanic. ClearMechanic is a platform to better connect auto mechanics with their customers. In an industry often considered technologically backward and rife with trust problems, ClearMechanic is meant to offer transparency and online accessibility to auto-owners. Using ClearMechanic, customers can go online to see the where their repair is in the work queue, learn about the repair being done, and interact with the repair shop. It also serves a marketplace for complementary products, such as accessories, insurance, repurchase options. The founder and CEO is Brad Simmons, a former student of my MBA class Managing Networked Businesses. www.clearmechanic.com
VigLink. VigLink is a startup that describes itself publicly as “building a unique platform for the real-time optimization of affiliate marketing." The founder, Oliver Roup is a recent HBS graduate and former student of Managing Networked Business. www.viglink.com
Cork'd. Cork'd is a social network for wine lovers. The founder is wine celebrity Gary Vaynerchuk, and the CEO is Lindsay Ronga, a former student in Managing Networked Businesses. Among other goals, Cork'd would like to match users with their favorite wines. www.corkd.com
SaleAwayWithMe. SaleAwayWithMe is a website that offers users customizable notifications about sales from their favorite brands. SaleAwayWithMe differentiates itself from spammy newsletters in that specific brands can be chosen, their sales are consolidated into a single list, and users can set thresholds (e.g. only include the most popular notices, such as sale notices that XX% of recipients click on.) SaleAwayWithMe is in a very early state, and was founded by former HBS student Sumir Meghani. www.saleawaywithme.com
I've recently spoken with all of the founders/managers of these companies, and each is willing to work with students who choose to study the business as part of the class project.
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