Wednesday, January 27, 2010
The Australian paired Kidney eXchange (AKX) goes live
"The Australian paired Kidney eXchange Program (AKX) is a nationwide live kidney donor exchange program which will become operational in January 2010 and operate under the auspices of the Australian Organ and Tissue Authority"
Tuesday, January 26, 2010
School choice in SF moves forward
Yesterday Muriel Niederle and Clayton Featherstone were among the presenters to the San Francisco Board of Education, speaking about possible designs for a new school choice system there. It seems that they are well on the way to a good outcome.
One of the Board members, Rachel Norton, has a blog on which she posted before and after accounts of the meeting:
Tonight’s student assignment meeting should be interesting!
Recap: Closing in on a student assignment policy
Here is a video of the whole meeting (but you can navigate a bit so you don't have to watch the full 3 hours: Muriel's testimony, from her slide presentation through answering of questions from the board is from 1:09 to 2:09 on the video).
For the technically inclined, papers about our prior work on school choice systems in NYC and Boston are here.
It has been mentioned in the SF discussions that our team of market designers has worked on a number of problems aside from school choice, so here are background links on some of them for SF readers who are interested:
National Resident Matching Program and related medical labor markets
Gastroenterologists, Orthopaedic surgeons
Kidney Exchange
AEA market for new economists
One of the Board members, Rachel Norton, has a blog on which she posted before and after accounts of the meeting:
Tonight’s student assignment meeting should be interesting!
Recap: Closing in on a student assignment policy
Here is a video of the whole meeting (but you can navigate a bit so you don't have to watch the full 3 hours: Muriel's testimony, from her slide presentation through answering of questions from the board is from 1:09 to 2:09 on the video).
For the technically inclined, papers about our prior work on school choice systems in NYC and Boston are here.
It has been mentioned in the SF discussions that our team of market designers has worked on a number of problems aside from school choice, so here are background links on some of them for SF readers who are interested:
National Resident Matching Program and related medical labor markets
Gastroenterologists, Orthopaedic surgeons
Kidney Exchange
AEA market for new economists
Closing NY City High Schools
The NY Times has a story by Sharon Otterman on closing "persistently lowest performing" high schools. These are often the large, unscreened schools that serve, or try to serve, the hardest to educate students.
"Since 2002, the city has closed or is in the process of closing 91 schools, replacing them with smaller schools and charter schools, often several in the same building, with new leadership and teachers. This year, the city has proposed phasing out 20 schools, the most in any year. It is also the first year in which the city is required to hold public hearings at each school proposed for closing, as a result of a change in the mayoral control law that resulted from complaints about an insufficient role for parents. "
"The city’s Education Department says that on the whole, the closings have been a success. The small high schools created in the shells of old large high schools have average graduation rates of 75 percent, 15 percent higher than in the city as a whole and far greater than those of the schools they replaced."
"A study last year by the Center for New York City Affairs at the New School backed the chancellor’s argument that students at the smaller schools — which are organized around themes like science or community service — fare better. But the study also found evidence of a domino effect at the large high schools.
Because the new schools, at first, accepted relatively few special education and non-English-speaking students, those students began enrolling in greater numbers in the remaining large high schools. Overall enrollment increased at many large high schools, and attendance fell. “While a few schools were successful in absorbing such students, most were not,” the report said. "
"The Columbus student body is in constant flux. Because the school has unscreened admissions, it takes children expelled from charter schools, released from juvenile detention, and others on a near-daily basis: last year, 359 of its 1,400 students arrived between October and June. Even after the city proposed the school’s closing in December, it received 27 more students. ...
"The city does not dispute that Columbus has been dealt a tough hand, but it argues that other high schools with a similar population — 26 percent are classified as special education and 18 percent are not fluent in English — have had better results. Columbus was also included on New York State’s list of “persistently lowest performing” schools last week, which requires the city to produce a plan either for closing or for staff changes and reorganization of the school."
Update: January 27. City Panel Approves Closing of 19 Schools
"Since 2002, the city has closed or is in the process of closing 91 schools, replacing them with smaller schools and charter schools, often several in the same building, with new leadership and teachers. This year, the city has proposed phasing out 20 schools, the most in any year. It is also the first year in which the city is required to hold public hearings at each school proposed for closing, as a result of a change in the mayoral control law that resulted from complaints about an insufficient role for parents. "
"The city’s Education Department says that on the whole, the closings have been a success. The small high schools created in the shells of old large high schools have average graduation rates of 75 percent, 15 percent higher than in the city as a whole and far greater than those of the schools they replaced."
"A study last year by the Center for New York City Affairs at the New School backed the chancellor’s argument that students at the smaller schools — which are organized around themes like science or community service — fare better. But the study also found evidence of a domino effect at the large high schools.
Because the new schools, at first, accepted relatively few special education and non-English-speaking students, those students began enrolling in greater numbers in the remaining large high schools. Overall enrollment increased at many large high schools, and attendance fell. “While a few schools were successful in absorbing such students, most were not,” the report said. "
"The Columbus student body is in constant flux. Because the school has unscreened admissions, it takes children expelled from charter schools, released from juvenile detention, and others on a near-daily basis: last year, 359 of its 1,400 students arrived between October and June. Even after the city proposed the school’s closing in December, it received 27 more students. ...
"The city does not dispute that Columbus has been dealt a tough hand, but it argues that other high schools with a similar population — 26 percent are classified as special education and 18 percent are not fluent in English — have had better results. Columbus was also included on New York State’s list of “persistently lowest performing” schools last week, which requires the city to produce a plan either for closing or for staff changes and reorganization of the school."
Update: January 27. City Panel Approves Closing of 19 Schools
Spring 2010 courses in Market Design in Boston/Cambridge
Susan Athey at Harvard and Tayfun Sonmez at Boston College will both be teaching market design courses this semester, and Peter Coles and Benjamin Edelman will be teaching an MBA class at HBS called Managing Networked Businesses, that has a substantial focus on entrepreneurial market design.
Susan Athey: Economics 2056b. Topics in Market Design Catalog Number: 0402 Half course (spring term). Tu., Th., 1–2:30. EXAM GROUP: 15, 16Studies topics in market design, focusing on auctions, auction-based marketplaces and platform markets. Covers methods and results from theory, empirical work, econometrics and experiments, highlighting practical issues in real-world design.
Tayfun Sonmez: EC 802 Advanced Microeconomic Theory (Spring: 3)In recent years, auction theory and matching theory have found applications in many interesting real-life problems from a market/mechanism design perspective. Topics of this course include the theory of matching markets, multi-object auctions, school choice and kidney exchange.
Susan Athey: Economics 2056b. Topics in Market Design Catalog Number: 0402 Half course (spring term). Tu., Th., 1–2:30. EXAM GROUP: 15, 16Studies topics in market design, focusing on auctions, auction-based marketplaces and platform markets. Covers methods and results from theory, empirical work, econometrics and experiments, highlighting practical issues in real-world design.
Tayfun Sonmez: EC 802 Advanced Microeconomic Theory (Spring: 3)In recent years, auction theory and matching theory have found applications in many interesting real-life problems from a market/mechanism design perspective. Topics of this course include the theory of matching markets, multi-object auctions, school choice and kidney exchange.
Monday, January 25, 2010
Pay to play at Russian universities
The Chronicle of Higher Education reports on an anti-corruption campaign at Kazan State University: A Russian University Gets Creative Against Corruption (gated, unfortunately, but the excerpts below give you the idea).
"Too many students and professors have a "pay to play" mentality, reformers say, in which grades and test scores are bought and sold.
Anticorruption videos are shown daily. Students participate in classroom discussions about the problem. Kazan State's rector, Myakzyum Salakhov, has installed video cameras in every hallway and classroom, so that the security department can watch students and professors in every corner of the university to catch any bribes as they are made."
...
"Across Russia, bribery and influence-peddling are rife within academe. Critics cite a combination of factors: Poor salaries lead some professors to pocket bribes in order to make ends meet. Students and their families feel they must pay administrators to get into good universities, if only because everyone else seems to be doing it. And local government officials turn a blind eye, sometimes because they, too, are corrupt."
...
"Students and administrators alike say that bribery is rampant on the campus, and that it includes everyone from students to department chairs.
"Corruption is just a routine we have to deal with," says Alsu Bariyeva, a student activist and journalism major who joined the campaign after a professor in the physical-culture department suggested that she pay him to get credit for her work that semester. She paid.
Several students said they once saw a list of prices posted in the hallway of the law department. The cost of a good grade on various exams ranged from $50 to $200. Students from other departments report similar scenarios.
Many people on the campus identify the arrest last March of the head of the general-mathematics department as a turning point. Police, tipped off by students and parents, charged in and arrested Maryan Matveichuk, 61, as he was pocketing thousands of rubles from a student for a good mark on a summer exam.
The police investigation concluded that in at least six instances Mr. Matveichuk, a respected professor, had accepted bribes of 4,000 to 6,000 rubbles, or about $135 to $200, from students in other departments for good grades on their math exams and courses.
Last September a court in Kazan found the math professor guilty of accepting a total of 29,500 rubles, or $1,000, in bribes, issued a suspended sentence of three years in prison, and stripped him of his teaching credential.
Mr. Matveichuk's arrest inspired Mr. Salakhov, the rector, to form an anticorruption committee, including administrators and students."
"Too many students and professors have a "pay to play" mentality, reformers say, in which grades and test scores are bought and sold.
Anticorruption videos are shown daily. Students participate in classroom discussions about the problem. Kazan State's rector, Myakzyum Salakhov, has installed video cameras in every hallway and classroom, so that the security department can watch students and professors in every corner of the university to catch any bribes as they are made."
...
"Across Russia, bribery and influence-peddling are rife within academe. Critics cite a combination of factors: Poor salaries lead some professors to pocket bribes in order to make ends meet. Students and their families feel they must pay administrators to get into good universities, if only because everyone else seems to be doing it. And local government officials turn a blind eye, sometimes because they, too, are corrupt."
...
"Students and administrators alike say that bribery is rampant on the campus, and that it includes everyone from students to department chairs.
"Corruption is just a routine we have to deal with," says Alsu Bariyeva, a student activist and journalism major who joined the campaign after a professor in the physical-culture department suggested that she pay him to get credit for her work that semester. She paid.
Several students said they once saw a list of prices posted in the hallway of the law department. The cost of a good grade on various exams ranged from $50 to $200. Students from other departments report similar scenarios.
Many people on the campus identify the arrest last March of the head of the general-mathematics department as a turning point. Police, tipped off by students and parents, charged in and arrested Maryan Matveichuk, 61, as he was pocketing thousands of rubles from a student for a good mark on a summer exam.
The police investigation concluded that in at least six instances Mr. Matveichuk, a respected professor, had accepted bribes of 4,000 to 6,000 rubbles, or about $135 to $200, from students in other departments for good grades on their math exams and courses.
Last September a court in Kazan found the math professor guilty of accepting a total of 29,500 rubles, or $1,000, in bribes, issued a suspended sentence of three years in prison, and stripped him of his teaching credential.
Mr. Matveichuk's arrest inspired Mr. Salakhov, the rector, to form an anticorruption committee, including administrators and students."
Sunday, January 24, 2010
Sex for the disabled and healthcare
The London Times asks: Is sex for the disabled the last taboo?
"The sexual feelings of disabled people have long been ignored. Now the medical profession is debating the issue"
The issue is not sex, so much as sex workers as a part of health care, and the role that the health care system should play, particularly for the most severely disabled patients who may need logistical support from health care workers .
The report is in connection with a conference called " “Disability: sex, relationships and pleasure”, which is being hosted by the Royal Society of Medicine in Central London. It aims to educate carers about the sexual needs of patients and to introduce disabled people to available support networks. It is backed by the Sexual Health and Disability Alliance (SHADA) and the Tender Loving Care Trust (TLC), which help to put disabled people in touch with appropriate sexual and therapeutic services, and offer confidential support and advice on sexual matters.
Tuppy Owens, the founder of the TLC, campaigns for the sexual needs of disabled people to be recognised by care workers. “Sex is right at the bottom of the list when it comes to their care requirements,” she says. “But they have a right to enjoy all elements of life just like everyone else. It is also important that they have access to sex workers because they don’t have the same opportunities as the average person to explore their bodies."
...
"The Sexual Offences Act allows care workers to help disabled patients to book sex workers over the telephone, provided they do not become involved in the negotiation of fees. But there have been many reported cases of authorities stepping in to stop the practice.
“The problem is that many health professionals think it is illegal,” says Owens. “The TLC has had calls from carers who say that they have even considered giving in their notice out of frustration that they are unable to help patients seeking a sexual service that could make them happier.”
Many high-profile names have backed the TLC’s cause, including Lord Faulkner of Worcester, Baroness Miller of Chilthorne Domer and the philosopher and author A. C. Grayling, but no one has gone so far as to suggest that sex workers should be paid for by the NHS. "
"The sexual feelings of disabled people have long been ignored. Now the medical profession is debating the issue"
The issue is not sex, so much as sex workers as a part of health care, and the role that the health care system should play, particularly for the most severely disabled patients who may need logistical support from health care workers .
The report is in connection with a conference called " “Disability: sex, relationships and pleasure”, which is being hosted by the Royal Society of Medicine in Central London. It aims to educate carers about the sexual needs of patients and to introduce disabled people to available support networks. It is backed by the Sexual Health and Disability Alliance (SHADA) and the Tender Loving Care Trust (TLC), which help to put disabled people in touch with appropriate sexual and therapeutic services, and offer confidential support and advice on sexual matters.
Tuppy Owens, the founder of the TLC, campaigns for the sexual needs of disabled people to be recognised by care workers. “Sex is right at the bottom of the list when it comes to their care requirements,” she says. “But they have a right to enjoy all elements of life just like everyone else. It is also important that they have access to sex workers because they don’t have the same opportunities as the average person to explore their bodies."
...
"The Sexual Offences Act allows care workers to help disabled patients to book sex workers over the telephone, provided they do not become involved in the negotiation of fees. But there have been many reported cases of authorities stepping in to stop the practice.
“The problem is that many health professionals think it is illegal,” says Owens. “The TLC has had calls from carers who say that they have even considered giving in their notice out of frustration that they are unable to help patients seeking a sexual service that could make them happier.”
Many high-profile names have backed the TLC’s cause, including Lord Faulkner of Worcester, Baroness Miller of Chilthorne Domer and the philosopher and author A. C. Grayling, but no one has gone so far as to suggest that sex workers should be paid for by the NHS. "
Commodification of the body, in Economic Sociology
The November 2009 issue of Economic Sociology, The European Electronic Newsletter, is largely devoted to discussion of "commodification of the body." Here are the articles, which concern cadavers, organs for transplantation, blood, and eggs and sperm.
A Market for Human Cadavers in All but Name by Michel Anteby
The Tyranny and the Terror of the Gift by Nancy Scheper-Hughes
Honestly Embracing Markets in Human Organs for Transplantation by Mark J. Cherry
Between Gift and Commodity: Blood Products in France by Sophie Chauveau
Debt and Gratitude by Lea Karpel
A Market for Human Cadavers in All but Name by Michel Anteby
The Tyranny and the Terror of the Gift by Nancy Scheper-Hughes
Honestly Embracing Markets in Human Organs for Transplantation by Mark J. Cherry
Between Gift and Commodity: Blood Products in France by Sophie Chauveau
Debt and Gratitude by Lea Karpel
Saturday, January 23, 2010
Jon Baron has a new blog
Jonathan Baron's new blog, Judgment misguided, starts with a great post on Troubles understanding health-insurance reform. Read it, and you're likely to want to add it to your bookmarks, as I did.
He gives a quick quiz on the relevant economics to a web sample of Americans, and finds that indirect effects (let alone equilibrium adjustments of prices and behavior) are hard to understand.
He gives a quick quiz on the relevant economics to a web sample of Americans, and finds that indirect effects (let alone equilibrium adjustments of prices and behavior) are hard to understand.
Prostitution and the internet
Scott Cunningham and Todd Kendall have two papers on prostitution, which discuss among other things how sex is sold on the internet:
“Prostitution, Technology and the Law: New Data and Directions” in Handbook on Family Law and Economics, Edward Elgar, Forthcoming 2010.
“Sex for Sale: Online Commerce in the World’s Oldest Profession in Crime Online: Correlates, Causes and Controls, ed. Tom Holt, Carolina Academic Press, Forthcoming 2010.
Along with sites that offer sex for sale, there's been a growth in sites that offer customer reviews. E.g. PunterNet, a site that reviews British prostitutes (but is on a California computer) became briefly famous when a British politician announced that she would ask California's governator to shut it down: Terminate degrading site - Harman "Harriet Harman says she has asked California governor Arnold Schwarzenegger to shut down a website containing reviews of prostitutes."
Friday, January 22, 2010
Texas regulation watch: horse floaters and eyebrow threaders
The WSJ brings us the story: Texas Horse Dentists Feel the Bite Of State Regulatory Oversight
"For a quarter-century, Mr. Mitz has practiced the obscure art of horse-teeth floating. Using instruments roughened with diamond grit, he has filed down hundreds of thousands of equine teeth so that they don't grow into sharp points that can cut the horses' cheeks or throw off their chewing rhythms."...
"Veterinary oversight boards in Texas and several other states have moved aggressively in recent years to rein in unlicensed floaters, ordering them to stop practicing or to work only under supervision of a licensed vet."
The horse floaters have a legal champion helping them defend themselves.
""We want to vindicate our clients' constitutional right to float horse teeth without arbitrary and unfair interference," says Clark Neily, a senior attorney with the Institute for Justice, a nonprofit libertarian law firm on a mission to block state governments from overregulating.
In Texas alone, the institute is fighting on behalf of eyebrow threaders (who use cotton thread to remove unwanted facial hair), wig servicers (who fit and style fake locks), equine massage therapists, interior designers, locksmiths and karate instructors. The institute's clients argue that the state has imposed costly and unnecessary requirements for training or licensing.
Fifty years ago, just 3% of American workers were regulated or licensed by government agencies, according to the Institute for Justice. Today, it's 35%."
Here's a previous post concerning regulation and licensing in Texas (and elsewhere).
"For a quarter-century, Mr. Mitz has practiced the obscure art of horse-teeth floating. Using instruments roughened with diamond grit, he has filed down hundreds of thousands of equine teeth so that they don't grow into sharp points that can cut the horses' cheeks or throw off their chewing rhythms."...
"Veterinary oversight boards in Texas and several other states have moved aggressively in recent years to rein in unlicensed floaters, ordering them to stop practicing or to work only under supervision of a licensed vet."
The horse floaters have a legal champion helping them defend themselves.
""We want to vindicate our clients' constitutional right to float horse teeth without arbitrary and unfair interference," says Clark Neily, a senior attorney with the Institute for Justice, a nonprofit libertarian law firm on a mission to block state governments from overregulating.
In Texas alone, the institute is fighting on behalf of eyebrow threaders (who use cotton thread to remove unwanted facial hair), wig servicers (who fit and style fake locks), equine massage therapists, interior designers, locksmiths and karate instructors. The institute's clients argue that the state has imposed costly and unnecessary requirements for training or licensing.
Fifty years ago, just 3% of American workers were regulated or licensed by government agencies, according to the Institute for Justice. Today, it's 35%."
Here's a previous post concerning regulation and licensing in Texas (and elsewhere).
Progress towards a sensibly organized national kidney exchange
An important story has played out one more quite positive step in the dry prose of medical bureaucracy, in the form of a report of the Policy Oversight Committee of the Organ Procurement and Transplantation Network (OPTN) of the Health Resources and Services Administration (HRSA). (All of the reports are found here.)
The report in question is this one, OPTN/UNOS Policy Oversight Committee, Report to the Board of Directors, November 16-17, 2009, and the item in question has to do with how a pilot national kidney exchange might be organized, if it overcomes some hurdles presently standing in its way. In particular, the cumbersome review process is catching up with the progress being made in regional kidney exchanges, in which chains have become important, expecially since the introduction of Non-simultaneous kidney exchange chains .
"The Committee supports the Kidney Transplantation Committee’s proposal to include living donors and donor chains in the Kidney Paired Donation Pilot Program. (Item 3, Page 6)."
Here it is:
"3. Proposal to include non-directed living donors and donor chains in the Kidney Paired Donation Pilot Program.
Currently, the Kidney Paired Donation (KPD) Pilot Program only allows living donors with incompatible potential recipients to participate. Non-directed (or altruistic) living donors (those who are not linked to an incompatible potential recipient) have no way to enter the program. Also, candidate / donor pairs can only be matched in groups of two or three, and all donor nephrectomies in the group must occur simultaneously. This proposal would allow non-directed living donors to participate in the KPD Pilot Program and add donor chains as an option in the system. A donor chain occurs when a non-directed living donor gives a kidney to a recipient whose living donor in turn gives a kidney to another recipient and continues the chain. This proposal would allow two types of donor chains: open and closed. Closed chains start with a non-directed living donor and end with a donation to a recipient on the deceased donor waiting list. Open chains start with a non-directed living donor and end with a bridge donor who will start another segment in the open chain. In open chains, the
bridge donor nephrectomy does not occur at the same time as the other living donor nephrectomies. Donor chains have the potential to increase the number of transplants in a KPD system.
The Committee used the scorecard to assess this policy, and the proposal received an overall score of 23.5. The proposal received average score of greater than 2.3 in every category except patient safety and oversight, geographical equity, and operational effectiveness.
The Committee unanimously supported this proposal by a vote of 9 in favor, 0 opposed, and 0 abstentions."
The report in question is this one, OPTN/UNOS Policy Oversight Committee, Report to the Board of Directors, November 16-17, 2009, and the item in question has to do with how a pilot national kidney exchange might be organized, if it overcomes some hurdles presently standing in its way. In particular, the cumbersome review process is catching up with the progress being made in regional kidney exchanges, in which chains have become important, expecially since the introduction of Non-simultaneous kidney exchange chains .
"The Committee supports the Kidney Transplantation Committee’s proposal to include living donors and donor chains in the Kidney Paired Donation Pilot Program. (Item 3, Page 6)."
Here it is:
"3. Proposal to include non-directed living donors and donor chains in the Kidney Paired Donation Pilot Program.
Currently, the Kidney Paired Donation (KPD) Pilot Program only allows living donors with incompatible potential recipients to participate. Non-directed (or altruistic) living donors (those who are not linked to an incompatible potential recipient) have no way to enter the program. Also, candidate / donor pairs can only be matched in groups of two or three, and all donor nephrectomies in the group must occur simultaneously. This proposal would allow non-directed living donors to participate in the KPD Pilot Program and add donor chains as an option in the system. A donor chain occurs when a non-directed living donor gives a kidney to a recipient whose living donor in turn gives a kidney to another recipient and continues the chain. This proposal would allow two types of donor chains: open and closed. Closed chains start with a non-directed living donor and end with a donation to a recipient on the deceased donor waiting list. Open chains start with a non-directed living donor and end with a bridge donor who will start another segment in the open chain. In open chains, the
bridge donor nephrectomy does not occur at the same time as the other living donor nephrectomies. Donor chains have the potential to increase the number of transplants in a KPD system.
The Committee used the scorecard to assess this policy, and the proposal received an overall score of 23.5. The proposal received average score of greater than 2.3 in every category except patient safety and oversight, geographical equity, and operational effectiveness.
The Committee unanimously supported this proposal by a vote of 9 in favor, 0 opposed, and 0 abstentions."
Thursday, January 21, 2010
Two new matching papers from Cal Tech
Federico Echenique, emailing from the left coast, sends along links for two new papers:
1) "Aggregate Matchings," joint with SangMok Lee and Matt Shum.
An aggregate matching market is a matching market (M,W,>) in the usual sense, but where we imagine that the elements of M and W are "types" of men and women, and that there may be more than one agent of each type. You can then study "aggregate matchings." For example with 3 types of men and women, these are matrices like
2 3 0
0 1 3
0 0 2
where there are 5 men of type m_1; 2 are married to women of type w_1 and 3 are married to women of type w_2; and so on.
Aggregate matchings are interesting because matching data often comes in this form, and many empirical papers use aggregate matchings.
The focus of the paper is on the empirical implications of stability for aggregate matchings. We ask when there are preferences that make an aggregate matching stable. It turns out that one has to look at a graph defined by the matrix; it's a graph you can draw on the matrix where the vertexes are all the non-zero entries, and there is an edge between v and v' iff they lie on the same row or column. Then the matrix is rationalizable iff the graph does not have two connected cycles. We also look a the model with transfers, and find that rationalizability with transfers is equivalent to the absence of cycles.
In the paper we develop econometric techniques for estimating preference parameters from imposing stability. The techniques are based on a moment inequality we obtain from stability. We have an illustration with US marriage data.
A PDF is in:
http://www.hss.caltech.edu/~fede/wp/aggregate_matchings.pdf
2) "Clearinghouses For Two-Sided Matching: An Experimental Study," joint with Alistair Wilson and Leeat Yariv.
This is an experimental paper. We wanted to test the Gale-Shapley mechanism in the lab. We were worried about the effects of direct revelation on experimenter demand: if you give subjects a preference, and then you ask them to report their preference, then they may start thinking about the motives behind the study. So we have a design where subjects go through the steps of the algorithm, making offers and holding on to proposals. We also think this design makes it easier to map actions into outcomes, compared to the direct revealaion alternative.
The findings are: First, 48% of the observed match outcomes are fully stable.
Among those markets ending at a stable outcome, a large majority culminates in the best stable matching for the receiving-side. Second, contrary to the theory, participants on the receiving-side of the algorithm rarely truncate their true preferences. In fact, it is the proposers who do not make offers in order of their preference, frequently skipping potential partners. Third, market char- acteristics affect behavior and outcomes: both the cardinal representation and the span of the core influence whether outcomes are stable or close to stable, as well as the number of turns it takes markets to converge to the final outcome.
A PDF is in:
http://www.hss.caltech.edu/~fede/wp/ech_wilson_yariv.pdf
1) "Aggregate Matchings," joint with SangMok Lee and Matt Shum.
An aggregate matching market is a matching market (M,W,>) in the usual sense, but where we imagine that the elements of M and W are "types" of men and women, and that there may be more than one agent of each type. You can then study "aggregate matchings." For example with 3 types of men and women, these are matrices like
2 3 0
0 1 3
0 0 2
where there are 5 men of type m_1; 2 are married to women of type w_1 and 3 are married to women of type w_2; and so on.
Aggregate matchings are interesting because matching data often comes in this form, and many empirical papers use aggregate matchings.
The focus of the paper is on the empirical implications of stability for aggregate matchings. We ask when there are preferences that make an aggregate matching stable. It turns out that one has to look at a graph defined by the matrix; it's a graph you can draw on the matrix where the vertexes are all the non-zero entries, and there is an edge between v and v' iff they lie on the same row or column. Then the matrix is rationalizable iff the graph does not have two connected cycles. We also look a the model with transfers, and find that rationalizability with transfers is equivalent to the absence of cycles.
In the paper we develop econometric techniques for estimating preference parameters from imposing stability. The techniques are based on a moment inequality we obtain from stability. We have an illustration with US marriage data.
A PDF is in:
http://www.hss.caltech.edu/~fede/wp/aggregate_matchings.pdf
2) "Clearinghouses For Two-Sided Matching: An Experimental Study," joint with Alistair Wilson and Leeat Yariv.
This is an experimental paper. We wanted to test the Gale-Shapley mechanism in the lab. We were worried about the effects of direct revelation on experimenter demand: if you give subjects a preference, and then you ask them to report their preference, then they may start thinking about the motives behind the study. So we have a design where subjects go through the steps of the algorithm, making offers and holding on to proposals. We also think this design makes it easier to map actions into outcomes, compared to the direct revealaion alternative.
The findings are: First, 48% of the observed match outcomes are fully stable.
Among those markets ending at a stable outcome, a large majority culminates in the best stable matching for the receiving-side. Second, contrary to the theory, participants on the receiving-side of the algorithm rarely truncate their true preferences. In fact, it is the proposers who do not make offers in order of their preference, frequently skipping potential partners. Third, market char- acteristics affect behavior and outcomes: both the cardinal representation and the span of the core influence whether outcomes are stable or close to stable, as well as the number of turns it takes markets to converge to the final outcome.
A PDF is in:
http://www.hss.caltech.edu/~fede/wp/ech_wilson_yariv.pdf
Mathoverflow.net
Mathoverflow.net is an internet site on which people can ask and answer math questions. It elicits a good deal of effort for free, in an Open Science, reputation-mediated way.
It has a reputation system, based on the votes "up" your questions and answers get. Other users can also reduce your reputation by 2 points, at a cost of 1 point to themselves, if they don't like your posts.
There's also a set of distinctions that users can earn, called badges.
HT: Aaron Roth
It has a reputation system, based on the votes "up" your questions and answers get. Other users can also reduce your reputation by 2 points, at a cost of 1 point to themselves, if they don't like your posts.
There's also a set of distinctions that users can earn, called badges.
HT: Aaron Roth
Wednesday, January 20, 2010
Peer review and markets for ideas, in law and science
Most scientific journals involve "peer review," where the peers in question are supposed to be experts on the subject of a particular submitted article. Because reviewers' time is scarce, the presumption is that a paper submitted to a peer reviewed journal is not currently being submitted anywhere else. The author submits the paper, and waits for a review (either a rejection, a revise-and-resubmit, or an acceptance). Depending on the field and the journal this can happen quickly, or (for economics journals) slowly.
Law Reviews are different. Authors submit to multiple journals simultaneously, and the papers are reviewed not by peers but by the third year law students who edit that year's edition of their law school's Review. And well-received authors don't get "acceptances" they get "offers" to publish, which typically have a short deadline, e.g. 24 hours. In that time they can contact one of the other law reviews to whom they have submitted the paper and try to get it accepted there.
For example, the submissions page of the University of Chicago Law Review has the following invitation to ask for an Expedited Review: "If you have received a formal offer of publication from another journal and would like to receive an expedited review by the University of Chicago Law Review, please contact us at lrarticles[at]law.uchicago.edu. When requesting an expedited review, please put "Expedite" as the subject of your email and include in the text:
1) The author name and title of your manuscript; 2) The name of the journal that has extended an offer to you; 3) The date that the offer expires; 4) The phone number or email address of a contact person at that journal;5) An electronic attachment of your article (plus C.V. or cover letter) to facilitate and accelerate the process. The University of Chicago Law Review will attempt to honor all requests for expedited review for which the above information is provided. ..."
But there is an experiment afoot to change the way law review articles are reviewed, and to try to have peer review while still allowing authors to submit to multiple journals simultaneously: Mainstream law review tries peer review
The idea is to have the reviews done first in a clearinghouse called the Peer Reviewed Scholarship Marketplace "The Peer Reviewed Scholarship Marketplace (“PRSM”), a consortium of student-edited legal journals, exists to provide student-editors with peer evaluations of legal-scholarship manuscripts and to assure the publication of quality articles. PRSM connects authors and journals with subject matter experts, who through their reviews provide editors with the information they need to make informed decisions regarding article selection. With PRSM, the future of legal-scholarship publishing has arrived."
"The Peer Reviewed Scholarship Marketplace (“PRSM”) began with the South Carolina Law Review’s Peer Review Pilot Program... Numerous authors submitted manuscripts to the South Carolina Law Review, and many other legal scholars and practitioners volunteered to serve as peer reviewers. Relying on the reviewers’ evaluations, the South Carolina Law Review chose three articles for publication in a special Peer Review Issue (Volume 60, Book 4). This special issue also featured a favorable foreword by Judge Richard A. Posner as well as an essay describing the South Carolina Law Review’s experience with peer review.
The Pilot Program’s success encouraged the creation of PRSM, a consortium of student-edited legal journals that believe that peer review can enhance the quality of the articles that journals select and ultimately publish. PRSM works much like the familiar manuscript submission vehicle ExpressO but with a peer review component. Authors submit their work exclusively to PRSM, whose administrators then arrange for double-blind peer review of each manuscript. After six weeks, PRSM members will receive a copy of the article with the reviews, which will assist the student-editors in publication decisions. As with ExpressO, members will make their own independent offers to authors, who are free to accept or decline. If an author is unsatisfied with all offers—or receives none after a designated date—he or she is free to resubmit his or her reviewed manuscript through ExpressO or another preferred vehicle.
PRSM thus benefits all parties: authors, reviewers, journals, and the legal community that relies on scholarship published in student-edited journals. All authors receive valuable feedback from their peers, and successfully placed authors further benefit from the “peer reviewed” certification of their published manuscripts. Reviewers are offered an opportunity to comment on new scholarship pertinent to their areas of expertise and thereby participate in the “gate-keeping” article selection process. Student-edited journals are given an additional tool to spot and select the most novel and valuable research for publication. Finally, PRSM’s peer review process produces higher quality scholarship for the legal community that reads and relies on the profession’s journals.
For more information about South Carolina Law Review’s experience with the Peer Review Pilot Program and creation of PRSM, go here."
Apparently law journals in the UK are more like economics journals than like American law reviews, in that authors can only submit to one journal at a time, and submissions are peer reviewed (see Comparative journal submission experiences by John Ip).
In the meantime, a peer-review holdout in the sciences is moving to peer review. The Proceedings of the National Academy of Science, the journal published by the honorific society from which it takes its name, had a tradition of allowing NAS members to "communicate" papers without a refereeing process. For some time now that has coexisted with a peer review process; some papers are reviewed, others simply communicated. Next year that will come to an end, and all papers will be reviewed: PNAS will eliminate Communicated submissions in July 2010.
The problem is that communicated papers were apparently of very uneven quality. (Some biologists I know claim that PNAS stands for "post-Science and Nature," as papers are only sent there after being rejected by those two other journals.) And while there is a very sensible scientific tradition of simply ignoring bad papers, some of the ones that appeared were apparently embarassing: Peer Review Failure?
Peer review is undoubtedly a part of the answer to the larger question about why journals persist at all given the growth of the internet: Why Hasn’t Scientific Publishing Been Disrupted Already?
Tuesday, January 19, 2010
Random allocation, preferences, and welfare: a fish story
Flying from Madrid to Boston on an Airbus with two aisles not long ago, two stewardesses proceeded in parallel down the aisles offering food. I asked for the fish, but the stewardess in my aisle was already out of fish. Speaking to her colleague in the other aisle, she ascertained that her colleague still had some fish. Rather than pass the fish across the (empty) seat between them, “my” stewardess told me that, if her colleague still had fish when she completed her aisle, then I could have it. (I chose the vegetable dish…)
We see similar issues when changes are discussed in how to allocate deceased-donor organs for transplants, or some other policy where there has been a previous decision on an order of allocation to randomly arriving agents. To have passed the fish across to me would have disadvantaged some passenger who, but for the demand for fish on my side of the plane, would have been able to eat fish…
Of course, assuming that on which side of the plane passengers are seated is random, the policy of allowing fish to be passed from side to side and not just from front to back would have the same ex-ante welfare properties. But, once the passengers are seated, any change in policy would likely help some passenger only by hurting another.
This kind of discussion comes up from time to time in the allocation of school places, as well as transplant organs.
We see similar issues when changes are discussed in how to allocate deceased-donor organs for transplants, or some other policy where there has been a previous decision on an order of allocation to randomly arriving agents. To have passed the fish across to me would have disadvantaged some passenger who, but for the demand for fish on my side of the plane, would have been able to eat fish…
Of course, assuming that on which side of the plane passengers are seated is random, the policy of allowing fish to be passed from side to side and not just from front to back would have the same ex-ante welfare properties. But, once the passengers are seated, any change in policy would likely help some passenger only by hurting another.
This kind of discussion comes up from time to time in the allocation of school places, as well as transplant organs.
Monday, January 18, 2010
Onur Kesten on discrete allocation
Onur Kesten of CMU has two recent papers that offer new views of old problems.
Kesten, Onur , Why do popular mechanisms lack efficiency in random environments?
Journal of Economic Theory, Volume: 144 Issue: 5 Pages: 2209-2226 SEP 2009
"We consider the problem of randomly assigning n indivisible objects to n agents. Recent research introduced a promising mechanism, the probabilistic serial that has superior efficiency properties than the most common real-life mechanism random priority. On the other hand, mechanisms based on Gale's celebrated top trading cycles method have long dominated the indivisible goods literature (with the exception of the present context) thanks to their outstanding efficiency features. We present an equivalence result between the three kinds of mechanisms, that may help better understand why efficiency differences among popular mechanisms might arise in random environments. This result also suggests that the probabilistic serial and the random priority mechanisms can be viewed as two top trading cycles based mechanisms that essentially differ in the initial conditions of the market before trading starts."
Kesten, Onur, "SCHOOL CHOICE WITH CONSENT, Quarterly Journal of Economics, forthcoming.
"An increasingly popular practice for student assignment to public schools in the U.S. is the use of school choice systems. The celebrated Gale-Shapley student-optimal stable mechanism (SOSM) has recently replaced two de.cient student assignment mechanisms that were in use in New York City and Boston. We provide theoretical evidence that the SOSM outcome may produce large welfare losses. Then we propose an e¢ ciency adjusted deferred acceptance mechanism (EADAM) that allows a student to consent to waive a certain priority that has no e¤ect on his assignment. Under EADAM a consenting student causes himself no harm, but may help many others bene.t as a consequence. We show that EADAM can recover any welfare losses due to SOSM while also preserving immunity against strategic behavior in a particular way. It is also possible to use EADAM to eliminate welfare losses due to randomly breaking ties in student priorities."
Kesten, Onur , Why do popular mechanisms lack efficiency in random environments?
Journal of Economic Theory, Volume: 144 Issue: 5 Pages: 2209-2226 SEP 2009
"We consider the problem of randomly assigning n indivisible objects to n agents. Recent research introduced a promising mechanism, the probabilistic serial that has superior efficiency properties than the most common real-life mechanism random priority. On the other hand, mechanisms based on Gale's celebrated top trading cycles method have long dominated the indivisible goods literature (with the exception of the present context) thanks to their outstanding efficiency features. We present an equivalence result between the three kinds of mechanisms, that may help better understand why efficiency differences among popular mechanisms might arise in random environments. This result also suggests that the probabilistic serial and the random priority mechanisms can be viewed as two top trading cycles based mechanisms that essentially differ in the initial conditions of the market before trading starts."
Kesten, Onur, "SCHOOL CHOICE WITH CONSENT, Quarterly Journal of Economics, forthcoming.
"An increasingly popular practice for student assignment to public schools in the U.S. is the use of school choice systems. The celebrated Gale-Shapley student-optimal stable mechanism (SOSM) has recently replaced two de.cient student assignment mechanisms that were in use in New York City and Boston. We provide theoretical evidence that the SOSM outcome may produce large welfare losses. Then we propose an e¢ ciency adjusted deferred acceptance mechanism (EADAM) that allows a student to consent to waive a certain priority that has no e¤ect on his assignment. Under EADAM a consenting student causes himself no harm, but may help many others bene.t as a consequence. We show that EADAM can recover any welfare losses due to SOSM while also preserving immunity against strategic behavior in a particular way. It is also possible to use EADAM to eliminate welfare losses due to randomly breaking ties in student priorities."
Sunday, January 17, 2010
Allocation of deceased donor livers
Ex-chief of transplant program indicted in cover-up of patient switch
"On Wednesday, a federal grand jury indicted the former director of the liver transplant program at St. Vincent Medical Center in Los Angeles, California, for allegedly lying about a liver accepted for one patient but transplanted instead into another patient who was lower on the waiting list."
"On Wednesday, a federal grand jury indicted the former director of the liver transplant program at St. Vincent Medical Center in Los Angeles, California, for allegedly lying about a liver accepted for one patient but transplanted instead into another patient who was lower on the waiting list."
Saturday, January 16, 2010
blue guitar
Market design lyrics:
"They said, 'You have a blue guitar,
You do not play things as they are.'
The man replied, 'Things as they are
Are changed upon the blue guitar.'"
Wallace Stevens, "The Man with the Blue Guitar"
"They said, 'You have a blue guitar,
You do not play things as they are.'
The man replied, 'Things as they are
Are changed upon the blue guitar.'"
Wallace Stevens, "The Man with the Blue Guitar"
Indian names for college sports teams
Some people find repugnant the once common use of Native American names for college sports teams, and the practice is in steep decline: Native American mascot controversy. Here's a 'man bites dog' story, however.
In Twist, Tribe Fights for College Nickname
"Sometime soon, the Fighting Sioux of the University of North Dakota were to be no more, another collegiate nickname dropped after being deemed hostile and abusive to American Indians.
Except that some members of the Spirit Lake Tribe, one of two groups of Sioux in the state, say they consider the nickname an honor and worry that abandoning it would send them one step closer to obscurity.
“When you hear them announce the name at the start of a hockey game, it gives you goose bumps,” said Frank Black Cloud, a tribal member. “They are putting us up on a pinnacle.”
And so, in a legal standoff that has turned some preconceptions upside down, North Dakota’s top state lawyers will be in court on Wednesday to oppose members of the Spirit Lake Tribe who have sued to preserve the Fighting Sioux name and logo, an image of an Indian in profile, feathers draping down."
It looks like the tide will be hard to turn however: Judge Throws Out Lawsuit Seeking to Preserve Fighting Sioux Mascot
In Twist, Tribe Fights for College Nickname
"Sometime soon, the Fighting Sioux of the University of North Dakota were to be no more, another collegiate nickname dropped after being deemed hostile and abusive to American Indians.
Except that some members of the Spirit Lake Tribe, one of two groups of Sioux in the state, say they consider the nickname an honor and worry that abandoning it would send them one step closer to obscurity.
“When you hear them announce the name at the start of a hockey game, it gives you goose bumps,” said Frank Black Cloud, a tribal member. “They are putting us up on a pinnacle.”
And so, in a legal standoff that has turned some preconceptions upside down, North Dakota’s top state lawyers will be in court on Wednesday to oppose members of the Spirit Lake Tribe who have sued to preserve the Fighting Sioux name and logo, an image of an Indian in profile, feathers draping down."
It looks like the tide will be hard to turn however: Judge Throws Out Lawsuit Seeking to Preserve Fighting Sioux Mascot
Friday, January 15, 2010
Ken Rogoff on grandmasters and growth
My colleague Ken Rogoff writes about two subjects he knows as well as anyone: Grandmasters and Global Growth.
Drawing analogies from the great progress in chess playing computer programs, he conjectures that artificial intelligence will power a lot of economic growth in the coming decade. I'm a bit skeptical, if only because AI has been the coming thing for at least a few decades now (remember expert systems?).
Of course, this may be a quibble about the "I" in AI. Herb Simon used to complain that the goal posts were constantly being moved; whenever computers became good at something that used to be thought to require intelligence, then "intelligence" would just be redefined. In this regard, I've been impressed at the big strides that have recently been taken in cheap, fast computerized translation: it's still a long way from passing the Turing test, but you can now tell at least what a web page is about in a lot of languages.
We're already seeing a lot of growth of computer assisted markets of all sorts, including many clearinghouses of the kind I often write about when I write about market design generally, including some of the developments in this past year. So maybe Ken is right, and after we enjoy the economic growth, we can quibble about whether these computerized markets and products are really smart...
Update: the February 11, 2010 New York Review of Books has an article by Gary Kasparov, The Chess Master and the Computer that includes a discussion of human-computer teams, i.e. of computer-assisted chess.
Drawing analogies from the great progress in chess playing computer programs, he conjectures that artificial intelligence will power a lot of economic growth in the coming decade. I'm a bit skeptical, if only because AI has been the coming thing for at least a few decades now (remember expert systems?).
Of course, this may be a quibble about the "I" in AI. Herb Simon used to complain that the goal posts were constantly being moved; whenever computers became good at something that used to be thought to require intelligence, then "intelligence" would just be redefined. In this regard, I've been impressed at the big strides that have recently been taken in cheap, fast computerized translation: it's still a long way from passing the Turing test, but you can now tell at least what a web page is about in a lot of languages.
We're already seeing a lot of growth of computer assisted markets of all sorts, including many clearinghouses of the kind I often write about when I write about market design generally, including some of the developments in this past year. So maybe Ken is right, and after we enjoy the economic growth, we can quibble about whether these computerized markets and products are really smart...
Update: the February 11, 2010 New York Review of Books has an article by Gary Kasparov, The Chess Master and the Computer that includes a discussion of human-computer teams, i.e. of computer-assisted chess.
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