Sunday, September 30, 2018

A black market in publishing fake science

ABC (the Australian one) has the story:
Inside the 'shadowy world' of China's fake science research black market

"When the cancer research journal Tumor Biology retracted 107 papers last year, a dubious new world record was set — and the world's scientists took notice.
"But it wasn't a first for the journal, now published by Sage. In 2016, it retracted 25 papers because of similar doubts over their integrity.
The incidents expose a deeper, darker problem for science globally.
A growing black market is peddling fake research papers, fake peer reviews, and even entirely fake research results to anyone who will pay.
"Organised crime in certain countries has realised there is a lot of money to be made here," medically-trained Dr Oransky said.
"The pressure on Chinese scientists to publish their work in prestigious, English-language journals is now immense.
This has created new opportunities for China's thriving black market.
Companies offering standard editing and translation services to scientists have, in some cases, become a source of serious fraud.

"People can ask them to produce a paper of a certain kind, and they will produce the figures, the data, everything, and give it to you.
"You see this kind of very large-scale fraud going on in China."
Professor Cong Cao, a leading scholar in innovation studies at the University of Nottingham Ningbo China, said the market for these kind of services is large.
"In China, for a scientist to be promoted, they have to have a certain number of papers," he said.
Chinese graduate students and medical clinicians now also face the same strict requirements.
Some universities also pay huge cash rewards — over $US40,000 — if a scientist succeeds in publishing in a high-profile journal like Science or Nature.
Many see these financial incentives as part of the problem, especially in a country where average academic salaries are very low.
"The incentives are all misaligned," Dr Oransky said.
Professor Cao said the aim was to encourage scientists to be innovative.
"[But] there are some unintended consequences of this kind of policy," he said.
"More than 600 papers have been retracted since 2012 for fake peer review, according to Dr Oransky.
"Scientific misconduct is a growing global concern, and there is a risk of singling out China as the only hotspot.
But the Chinese Government knows it has a serious problem.
"China's Ministry of Science and Technology will now manage investigations into scientific misconduct. This is a departure from other countries where individual institutions are often in charge, despite implicit conflicts of interest."

Saturday, September 29, 2018

In Italy, a proposal to tax brides whose dresses are too skimpy

Nico Lacetera, who has a fine eye for repugnant transactions, points me to a proposal involving repugnance from several points of view:

Venezia, una tassa sulla scollatura della sposa
G-translate: Venice, a fee on the neckline of the bride

"The initiative comes from the parish priest don Cristiano Bobbo, from the community of Oriago and Cà Sabbioni, near Mestre. "We could create a sort of offer to be redeemed in proportion to the decency of the bride's dress, which very often presents itself vulgar and vulgar. So those who are more undressed pay more ", wrote the parish priest in his column on the newsletter" La voce della riviera "

Friday, September 28, 2018

Bride price in rural China

The Washington Post has a story about efforts to cap rising bride prices in one Chinese rural town:

The ‘bride price’ in China keeps rising. Some villages want to put a cap on it.

"The new rule was taped onto doorways around town: Officials were limiting what a groom-to-be could pay for a bride.

"The going rate was about $38,000, or five times the average annual salary in this village about four hours outside of Beijing. Now, families were told to keep it below $2,900.

"Anything more and they would risk being accused of human trafficking.

"The “bride price” — cash, and possibly a house or other goodies to the bride-to-be’s parents — has been part of the marriage pact in most of China for centuries. The costs, though, are swelling as China copes with one of the biggest demographic imbalances in history."

Thursday, September 27, 2018

Postdocs in market design at Melbourne

Alex Nichifor directs my attention to this ad in the JOE:

The University of Melbourne

Faculty of Business and Economics
Centre for Market Design
Post-Doctoral Research Fellow(s)

JOE ID Number: 2018-02_111460587
Date Posted: 09/11/2018
Position Title/Short Description
Title: Post-Doctoral Research Fellow(s)
Section: International: Other Academic (Visiting or Temporary)
Location: Melbourne, Victoria, AUSTRALIA
JEL Classification: D -- Microeconomics
market design
microeconomic theory
Salary Range: AUD$98,775 – AUD$117,290 p.a plus superannuation
Full Text of JOE Listing:
The Centre for Market Design ( of the Department of Economics at the University of Melbourne seeks to appoint one or more Post-Doctoral Fellows with interests in market design, mechanism design, industrial organization and/or applied microeconomics. The objectives of the Centre are to: (i) undertake research in market design and its associated academic disciplines; (ii) support an innovative microeconomic policy agenda with the aim of solving significant social and economic problems through the design of policy mechanisms; (iii) build capability in theory and empirics pertaining to market design. Working collaboratively with a team of leading academics, researchers, and doctoral students, Post-Doctoral Fellows will conduct research in support of the agenda of the Centre along with developing their own research careers. Applications are sought from individuals with a variety of backgrounds and interests in market design and microeconomics, as the activities of the Centre span applied policy problems, field and lab experiments, data collection, econometric modelling, and data analysis, along with microeconomic theory. Salary and research support will be competitive and the starting date is negotiable.

To ensure full consideration, applications must be received by December 15, 2018.

Additional information is available from:

Wednesday, September 26, 2018

Repugnance in Malaysia: sex and punishment

Malaysia is a complicated place: here's a story from the Guardian, of judicial caning in Malaysia, and objections to it, partly because the caning was semi-public.

Women caned in Malaysia for attempting to have lesbian sex
Rare punishment was carried out in a courtroom and witnessed by up to 100 people

"Two women found guilty of attempting to have sex have been caned in Malaysia’s conservative north-eastern state of Terengganu, in the first punishment of its kind.

"The two women, aged 22 and 32, were caned six times each in the Terengganu sharia high court just after 10am, after the sentence was read out.

"The caning was carried out in the courtroom and was witnessed by up to 100 people, including the public.

"While women in Malaysia have been caned for sexual offences in the past, such as adultery, rights activists say this is the first time two women have been caned for attempting to have sex.

“The punishment was shocking and it was a spectacle,” Thilaga Sulathireh, an activist from the Malaysian rights group Justice for Sisters who was in court on Monday told the Guardian, “For all intents and purposes it was a public caning.”

Tuesday, September 25, 2018

NSF is looking for a new Division Director, Social and Economic Sciences, SBE

This is an important job in government science:

Division Director, Social and Economic Sciences, SBE

Serves as a member of the SBE Directorate leadership team and as a principal spokesperson in social and economic sciences for the Foundation.  Provides leadership and direction to the NSF Division responsible for funding research and education activities, both nationally and internationally, to develop and advance scientific knowledge and methods focusing on our understanding of individuals, social and organizational behavior by creating and sustaining social science infrastructure, and by supporting disciplinary and interdisciplinary research that advances knowledge in the social and economic sciences.  The incumbent has managerial and oversight responsibilities for the effective use of division staff and resources in meeting organizational goals and objectives (e.g., broadening participation).  Assesses needs and trends involving the social and economic sciences, implements overall strategic planning and policy setting for the Division, provides leadership and guidance to Division staff members, determines funding requirements, prepares and justifies budget estimates, balances program needs, allocates resources, oversees the evaluation of proposals and recommendations for awards and declinations, and represents NSF to relevant external groups.  Supervises and provides leadership and guidance to senior staff (Deputy Division Director), program officers, administrative and support personnel.  Fosters partnerships with other Divisions, Directorates, Federal agencies, scientific organizations, and the academic community.

I'm a big fan of the NSF and the work it does, and very recently traveled to Washington D.C. to say thank you:

"And thank you to the NSF, and particularly to the Social, Behavioral and Economic Sciences Directorate, which must be one of the most cost-effective investments the government makes.  Social science isn’t very expensive, but it can be incredibly valuable. It can save lives.

"On a personal note, all of my work that was cited by the Nobel Prize committee was begun with funding from the NSF. Dan Newlon was the legendary director of the SBE Directorate, and he nurtured a generation of economists who made big changes in how economics is done. In the early 1990’s, when I was discouraged by the progress I was making on understanding matching, he encouraged me to stay the course. So for me, the NSF support was about much more than funding."
Here's the set of my blog posts that mention the NSF

Monday, September 24, 2018

Are there too many interviews for medical residencies and fellowships? Should there be an interview Match?

A recent article in JAMA considers the question in the title of this post:

September 21, 2018
Matching for Fellowship Interviews
Marc L. Melcher, MD, PhD; Itai Ashlagi, PhD; Irene Wapnir, MD

"Most surgical training programs interview many candidates because the consequences of not matching harms the reputation of the program and affects the work force of their services.5 Surveys of pediatric surgery program directors in 2011, 2012, and 2014 revealed that they interviewed a median of 24 to 30 candidates per year. However, the median rank at which the programs matched was less than 4, and programs never matched beyond their 12th choice, suggesting that they did not need to interview as many residents as they did.
"instituting an interview match may be one approach to help improve the interview selection process by reducing the large numbers of unfruitful and costly fellowship interviews. For example, Ashlagi et al7 found in a theoretical matching model that when candidates and programs each have highly heterogeneous preferences, limiting the number of interviews improved the efficiency of the matching process. Thus, fellowship interview matches represent an opportunity to reduce the excessive number of interviews and optimize the selection of applicants.

"A practical strategy that may achieve this goal is an interview match that precedes the existing match. After applications are submitted, candidates and programs submit rank lists that could be used to fill limited interview slots. Mechanisms that enable applicants and training programs to signal interest in each other have been proposed.4,7 By ranking candidates and programs highly, both essentially are respectively signaling their strong preference for each other.4 Therefore, fewer interviews might be sufficient for candidates and programs to identify mutually desirable matches and reduce the number and costs of interviews. If the program and candidate interview slots remain unfilled, a secondary match could be performed to fill unmatched interview slots.
"n conclusion, a well-designed interview match may help reduce excessive costly interviews while more efficiently pairing candidates and programs, so that both achieve as many highly ranked choices as possible. This strategy could be applied broadly to matching programs in other medical specialties and may be attractive at earlier career stages such as residency interviews."

And here's a related news story on the Stanford Medical School site:

The current fellowship interview process is cumbersome — Stanford researchers have a better idea

"In their fourth and fifth years, surgical residents are busy: They're caring for patients, assisting junior trainees and fulfilling their own training requirements. And that's not all: About 75 percent of these residents are scrambling to squeeze in interviews for fellowships across the country, often packing in between 6 and 15 interviews to ensure they secure a spot, Stanford transplant surgeon Marc Melcher, MD, PhD, told me.

"Fellowship program directors, including Stanford surgeon Irene Wapnir, MD, who directs the breast surgical fellowship, are similarly harried. To fill typically one position, the directors can interview 20 or more doctors to find a quality candidate whose interests match their program.
"The process is also expensive and time-consuming. When experienced residents leave, their coworkers need to cover for them, and the residents must pay their own way to travel to interviews, Melcher said.
"Melcher and Wapnir reached out to their Stanford Engineering colleague Itai Ashlagi, PhD, who specializes in the design and analysis of marketplaces, such as matching kidney donors with recipients.  Together with Alvin Roth, PhD, a Stanford economist, they're proposing a new fellowship interview matching system. Their concept appears in JAMA.
"The researchers propose two key changes. First, applicants and programs would signal their preferences for each other — before making travel arrangements and setting aside days of valuable physician time. In addition, the number of interviews for each fellowship program would be capped, as would the number of interviews for each candidate, Melcher said."

Sunday, September 23, 2018

Prostitution, brothels and police corruption in NYC

The NY Times has the story:
Brothels, Gambling and an Ex-Detective Mastermind: Officials Detail N.Y. Police Scandal

"It was a sweeping and complex criminal enterprise: brothels in Brooklyn, where 15-minute sexual encounters added up to more than $2 million in profits in a 13-month period, and nail salons in Queens, where managers, runners and agents placed bets in an old-school numbers racket.
And the mastermind was a retired New York City police detective who recruited at least seven police officers acting as foot soldiers, according to court documents charging the group on Thursday."
Here's an example of the strategic cat and mouse game that used the inside information of the "ex-detective mastermind":

"He knew that undercover officers investigating prostitution are not allowed to expose their genitals during their interactions with suspects, and so he made a rule to check new customers of the brothels: He insisted that the men “undress and allow themselves to be fondled to pass the brothel’s security screening,” the Queens district attorney’s office, which is prosecuting the officers and dozens of civilians, said."

Saturday, September 22, 2018

Surrogacy laws in Europe (mostly banned) and some countries where it is allowed

EuroNews has the story (and a map):

Where in Europe is surrogacy legal?

Families Through Surrogacy provides some information about countries around the world that allow surrogacy

The table below lists issues related to surrogacy in various countries which allow it.
AUSTRALIAAltruistic surrogacy only available. No donor or surrogate matching available. Advertising for surrogates not legal. All donors must be identified
Ethics committee approval often required. Foreigners cannot access surrogacy in Australia
User groups such as can provide
CANADAAltruistic surrogacy only available. Foreigners can access surrogacyvia seperate Egg donor providers
GREECEHeterosexual couples and single females eligible. Foreign nationals allowed to engage. Surrogate cannot be compensated beyond out-of-pocket expensesDonors, if required, must be anonymous. Eggs/embryos/sperm are able to be shipped directly from your registered clinic.
GEORGIACompensated surrogacy available  to heterosexual couples, including foreigners. Legal protections in place
INDIAOnly available for Indian residentsIn-country donors are anonymous however donor photos may be available other details provided: age, height, weight, previous donation history, children, blood group, education level/ occupation
ISRAELAltruistic surrogacy available only to heterosexual Israeli residents
KENYACompensated surrogacy available to locals and foreigners. No legal protection
LAOS Compensated Surrogacy available  to foreigners. Gestation & birth occurs in Thailand. No legal protection
MEXICO Tabasco state closed to surrogacy. Other states have no legal protections. Embryo transfer occurs in Cancun or Mexico City oftenCaucasian and Latin Sperm and Egg Donors available. Possible to bring your own surrogate and /or known donor. No waiting list
NIGERIAAltruistic and commercial surrogacy available to Nigerian heterosexual residentsEgg donors available
SOUTH AFRICAAltruistic surrogacy available to heterosexual South African residents
THAILANDOnly available altruistically to Thai residents
UKAltruistic surrogacy only available. Advertising for surrogates not legal foreigners cannot access surrogacy in UK
UKRAINEOnly heterosexual married couplesCaucasian, offer photos with family history, occupation/ area of study, previous donor history and physical details.
USAGay and heterosexual foreigners can access surrogacy here see surrogacy laws by US stateVery wide range available from donor agencies or privately

Expenses: $10,000
Legals & counselling: $22,000
Donor screening offered only if through an egg bank<5 td="" years="">Transfer of legal parentage available 4-6 months post birth if uncompensated surrogacy used domestically.
Surrogacy: $26,000 +
Local egg donor
add $5,000 +
according to age, genetics and lifestyle, mental and physical health 10 yearsIntended Parents named on birth certificate to meet the criteria of countries such as the UK, single surrogates are available and DNA testing is available
CANADA$90,000>15 years Transfer of parentage. Canadian passport available
KENYA$50,000<3 td="" years=""> No legal protection
UKSurrogacy UK, COTS>15 yearsTransfer of legal parentage available
USAIVF costs: $25,000
Surrogacy: $68,000
Other costs: $20,000
Varies by agency30 yearsParents names on the BC as mother and father
Surrogacy: $26,000 +
Local egg donor
add $5,000 +
according to age, genetics and lifestyle, mental and physical health~5 yearsIntended Parents named on birth certificate to meet the criteria of countries such as the UK, single surrogates are available and DNA testing is available. No eligibility for Ukraine citizenship
GREECEIVF: $20,100
Surrogacy: $44,000
Legals: $10,000+
Local egg donor: $1,360
10+ yearsRecently opened up to foreigners
Parents names on the BC as mother and father. Court case prior to IVF ensures transfer of parentage occurs before embryo transfer
MEXICO$80,000 (incl US egg donor)unknown<1 td="" year="">

Friday, September 21, 2018

Surrogacy in Spain

El Pais has the story:

Spanish couples undergoing surrogacy processes left in legal limbo in Ukraine
A total of 30 families are unable to secure passports for their children, after the Foreign Affairs Ministry says it has detected reports of malpractice and possible trafficking

"The Spanish Consulate in Kiev is examining the cases of 30 Spanish families currently in Ukraine and who are unable to obtain a Spanish passport for their babies after entering into what is an illegal practice back home: paying a surrogate to carry their child.
"The statement also warns against “entering into any surrogate pregnancy process within this context.”

"The Consulate was echoing a post on the Spanish Embassy’s website, which alerted Spanish nationals to the scams and shoddy practices of certain assisted-reproduction clinics in Ukraine, involving irregularities in the pregnancy process, induced abortions six weeks into the pregnancy so couples are forced to embark on another costly IVF treatment, and a general lack of medical attention during pregnancy.
Until July, babies born to surrogates in Ukraine were registered without fuss at the Spanish Consulate in Kiev.
"While registration has not yet been point-blank refused to any of the couples, a Foreign Office spokesman said shortly before the statement was issued that they were working with the local authorities to study alternatives in the case of such an event.
Given such a scenario, one possible solution would involve applying for a Ukrainian passport for the baby, thereby allowing he or she to leave Ukraine. And, once in Spain, the parentage could be established through the courts. This is the route being suggested by some of the lawyers representing the couples in question. It was also suggested by a staff member at the Consulate to a couple who are expecting their surrogate to give birth in the next few days.
Previously, the genetic Spanish father and the Ukrainian mother would be registered as the baby’s parents. “Once in Spain, the wife would then adopt her husband’s child with the prior consent of the surrogate mother,” says Franco Antonio Zenna, a lawyer who specializes in surrogacy issues and who is representing some of the couples. “It is as though a child has been born from a husband’s affair. At least that is how it has worked for the last seven or eight years at least.”

HT: Kim Krawiec

Thursday, September 20, 2018

Market design in Lund, September 2018

Arne Ryde Conference on
22-23 September 2018
Lund University, Lund, Sweden
Keynote speakers:
Estelle Cantillon, European Centre for Advanced Research in Economics and Statistics
Michael Ostrovsky, Stanford Graduate School of Business
Scott Kominers, Harvard Business School

Utku Unver, Boston College
Here's the full program.

Wednesday, September 19, 2018

Masataka Mori, Sensei (1938-2018)


Masataka Mori of Closter, age 85, born in Fukuoka, Japan, he attended Takushoku University and became captain of the Karate team. He came to the United States in 1963 as a karate instructor for the Japan Karate Association of Hawaii.   In 1968, he and his family moved to New York City, where he became the Chief Instructor of the JKA of New York and the Chief Instructor of JKA-Shotokan Karate-do International and attained the 9th Dan. In addition to teaching at his dojo, he had taught for years at New York colleges, including SUNY at Stony Brook, Columbia University, and CUNY, as well as a local schools, the Japanese Children’s Society. He often travelled abroad, acting as tournament arbitrator or judge, or teaching at various seminars.  This year marks his 50th year of teaching in New York City. He was an avid golf enthusiast and often participated in locally hosted Japanese American events.  Masataka Mori passed peacefully at his home in Closter, where he lived and gardened for forty years, surrounded by his devoted family. He is survived by Keiko, his wife of 61 years, his daughters Mayumi and Sayuri, their spouses Stephen and Alex, his four grandchildren, Allison, Kimiko, Andrew, Natalie, and Alexa and Kaitlin.
The Talmud advises us to "Provide for yourself a teacher and get yourself a friend..." Mori Sensei was a great teacher and an inspiring friend. I met him when I matriculated at Columbia in 1968, and his teaching and friendship were among the most memorable and important parts of my years there.

I last saw Sensei Mori in 2013, and my wife Emilie finally got a chance to meet him, after often hearing about him:
Sunday, June 9, 2013
Here's a video of a recent basics class (which even advanced students take with some regularity, to go over the very basic movements that are taught to beginners), which reminded me of learning the unfamiliar commands in 1968, and sometimes not being completely sure which were in Japanese and which in English...

Tuesday, September 18, 2018

A school choice mechanism from Taiwan, by Dur, Pathak, Song and Sönmez

Deduction Dilemmas: The Taiwan Assignment Mechanism

Umut M. DurParag A. PathakFei SongTayfun Sönmez

NBER Working Paper No. 25024
Issued in September 2018
NBER Program(s):Economics of EducationLabor Studies 
This paper analyzes the properties of the Taiwan mechanism, used for high school placement nationwide starting in 2014. In the Taiwan mechanism, points are deducted from an applicant's score with larger penalties for lower ranked choices. Deduction makes the mechanism a new hybrid between the well-known Boston and deferred acceptance mechanisms. Our analysis sheds light on why Taiwan's new mechanism has led to massive nationwide demonstrations and why it nonetheless still remains in use.

 "Loosely  speaking,  in  Taiwan’s deduction system, a students priority is reduced based on the order in which preferences are ranked.  Table 1 lists the schedule of points employed in 2014 across the largest districts in Taiwan.  For instance, in Jibei, the largest district with over 60,000 applicants, a student’s score at her second choice is reduced by 1, the score at her third choice is reduced by 2, and so on.  In Yunlin district, no points are deducted for the first four choices, and 2 points are 3 deducted from choices five through eight. The deduction system has now been in place for the last five years, from 2014-2018."

This system of deductions is used to determine each student's priority at each school, and allocations are then determined, by a deferred acceptance algorithm, based on student preferences and these school priorities.

Monday, September 17, 2018

Kidney exchange scheduled to begin in Hong Kong

The South China Morning Post has the story:

New kidney donation scheme starts in October after change in Hong Kong law allows strangers to donate organs to patients
This is aimed at speeding up the long waiting time for a suitable organ and surgeries will be done at four of the city’s 43 public hospitals

"The paired organ donation arrangement, made legal after Hong Kong passed an amendment to its Human Organ Transplant Ordinance last month, allows a donor-patient pair who may not be a match for each other to donate organs to another donor-patient pair and vice versa, so that patients on both sides get the transplants they need.
"There is a huge supply-demand gap for kidney transplants in the city. As of June 30 this year, there were 2,214 patients on the transplant list in Hong Kong but each year there are only about 80 living or deceased donors. Two years ago the average waiting time for a kidney was over four years.
"Before the change in the law, strangers could not make live donations to transplant patients. Couples had to be married for more than three years and friends needed to obtain approval from the Department of Health’s Human Organ Transplant Board for live donations.

"Professor Philip Li, the chairman of the authority’s Central Renal Committee said in the UK and the Netherlands, the paired kidney donation programme was very mature and they were now having a very large number of successful matchings.

 “In Hong Kong, we are just starting, it will be quite a while before we actually see a significant effect,” Li said."

Sunday, September 16, 2018

The U.S. Chamber of Commerce honors ideas

Country songwriters Lee Thomas Miller and Wendell Mobley share some of their ideas and IP at the Ideas in Bloom party sponsored by the Chamber of Commerce

Last Wednesday I flew to Washington DC to join a Chamber of Commerce celebration of  ideas and intellectual property, in various categories.

The innovation awards are both for lines of work that the National Science Foundation funded, and they were introduced by the NSF director, Dr. France Córdova. (I am happy to go to DC to help showcase the great work that the NSF does...see my remarks at the end of this post.)

Here's a link to the announcement:

IP Champion for Excellence in Enforcement
Peter O’Doherty, Head, Economic Crime Directorate, City of London Police
Nick Court, Chief Detective, Police Intellectual Property Crime Unit, City of London Police

IP Champion for Excellence in Innovation
Alvin Roth, Founder, Kidney Exchange
Inderjit Jutla, Founder, Aluna

IP Champion for Excellence in Advocacy
Bart Herbison, President, Nashville Songwriters Association
Steve Bogart, Chairman, Nashville Songwriters Association

IP Champion for Excellence in Creativity
Kristie Macosko Krieger, Academy Award-nominated producer
Kira Goldberg, Executive Vice President, Production, 21st Century Fox

IP Champion for Excellence in IP Policy
Professor Liu Chuntian, Renmin University of China

IP Champion for Excellence in Innovation
Uzi Hanuni, CEO, Maxtech Networks

Musical Performance
Lee Thomas Miller, Nashville Mega-hit Songwriter
Wendell Mobley, Nashville Mega-hit Songwriter

And here's a link to a subsequent press release:

"IP Champion for Excellence in Innovation – Alvin Roth
"Since the first paired kidney exchange in 2000, thousands of people have received kidney transplants identified through paired exchanges."
I scored a personal max for (travel time)/(speaking time).  Here are my prepared remarks:

"I flew here today to say thank you: to the Chamber of Commerce for recognizing not just my work but also the role that the NSF plays in fostering scientific innovation. 

And thank you to the NSF, and particularly to the Social, Behavioral and Economic Sciences Directorate, which must be one of the most cost-effective investments the government makes.  Social science isn’t very expensive, but it can be incredibly valuable. It can save lives.

On a personal note, all of my work that was cited by the Nobel Prize committee was begun with funding from the NSF. Dan Newlon was the legendary director of the SBE Directorate, and he nurtured a generation of economists who made big changes in how economics is done. In the early 1990’s, when I was discouraged by the progress I was making on understanding matching, he encouraged me to stay the course. So for me, the NSF support was about much more than funding.

So:Thank you all for coming here tonight, thank you Dr. Córdova, thank you to the NSF for all your support, starting when I was very young, and thank you to the Chamber of Commerce."

Here's a video link (that seems to start only after the first minute or so, and the NSF section begins with Dr. Córdova at minute 1:33 and goes to 1:45...) 

Saturday, September 15, 2018

Envy free (not quite stable) matchings

It's hard for decentralized markets to achieve stable matchings (i.e. matchings with no blocking pairs) in the way that centralized clearinghouses can (and this is why we see some markets organized by clearinghouses).  So it's worthwhile looking at larger sets of outcomes, and in this paper we look at matchings such that any blocking pairs must involve an unfilled position--i.e. they are envy free in the sense that there are no blocking pairs in which some worker can take the job presently held by another worker.

Wu, Qingyun and Alvin E. Roth, “The Lattice of Envy-free Matchings,” Games and Economic Behavior, May 2018, 109, 201-211

The lattice of envy-free matchings


Envy-free matchings are matchings that can only be unstable with respect to a blocking pair of a worker with a firm that has some unfilled positions.
These envy-free but unstable matchings may arise in the course of filling “vacancy chains” following a worker's retirement.
The set of envy free matchings is a lattice under the partial ordering of the common preferences of the workers.


In a many-to-one matching model, we show that the set of envy-free matchings is a lattice. A Tarski operator on this lattice, which can be interpreted as modeling vacancy chains, has the set of stable matchings as its fixed points.
Here's an ungated version of the paper.