Practical insights from market design, in Japan

I was recently interviewed by Fuhito Kojima as part of a symposium conducted by the University of Tokyo Market Design Center on practical insights from market design. The whole symposium is available on YouTube.

All but one of the presentations are in Japanese (summarized below by Fuhito):

1. Introduction (Fuhito) 

 2. Our interview (in English) 

3. More explanation of the stable matching problem and its application to personnel assignment (Shunya Noda)

4. Application of stable matching algorithm in personnel allocation in a firm: My team helped our partner firm, Sysmex, introduce the DA algorithm (in fact, a modified "flexible" deferred acceptance algorithm proposed by Kamada and Kojima 2015 AER) in the assignment of new employees to different divisions of the firm. The firm has been using matching algorithm for 4 years now. Our partner from the firm talks about their experience.

5. Application to daycare assignments: My team is collaborating with a major government contractor for municipal governments IT system, CyberAgent. The project studies daycare-related data provided by  municipal governments and helps those government introduce and improve their matching algorithms of daycare seats to children. Our partner from the firm talks about our team's effort, e.g., how we convinced one city change algorithm from Boston-like mechanism to DA, and how we helped fine-tune their priority design to cope with problems in which kids with siblings were not matched as well as single kids.

 6. Application to auction: Shunya and his team helped an auction platform firm to introduce an auction mechanism for selling used electronic devices. His partner company, Aucnet, shares their experience.

 7. Q&A and closing remark (Fuhito)

Here's my interview with Fuhito

 

Predicting the future in Japan: Kojima, Narita, Saito and Uchida

A new book in Japanese has appeared, whose translated title is "Future Prediction of Geniuses."

My attempt to post about it caused html errors on the blog, so this is a replacement for the original post, with just a link to the twitter thread here: https://twitter.com/booksmagazine/status/1611291463291404288

Google translate works pretty well at letting English speakers know what it says.

Managing inter-district school choice, by Yuchiro Kamada and Fuhito Kojima

 Here's a paper that considers inter-district school choice, motivated by Tokyo day care centers.  I think  a similar problem arises in the EU in allocating foreign study opportunities for college students.

 Ekkyo Matching: How To Connect Separate Matching Markets For Welfare Improvement  By Yuichiro Kamada And Fuhito Kojima

Abstract. "We consider a school-choice matching model that allows for inter-district transfer of students, with the “balancedness” constraint: each student and school belongs to a region, and a matching is said to be balanced if, for each region, the outflow of students from that region to other regions is equal to the inflow of students from the latter to the former. Using a directed bipartite graph defined on students and schools, we characterize the set of Pareto efficient matchings among those that are individually rational, balanced and fair. We also provide a polynomial-time algorithm to compute such matchings. The outcome of this algorithm weakly improves student welfare upon the one induced when each region independently organizes a standard matching mechanism"

" In Japan ... allocation of slots at accredited daycares are conducted by individual municipal governments and, with few exceptions, a child can only attend a daycare in the municipality of their residence. The City of Tokyo, for example, is divided into 23 small municipalities ... and each conducts a matching independently. Due to the small sizes of the regions, many families would find inter-district admissions—which is called the ekkyo admission ... to be a viable option. Moreover, as a large metropolitan area, many people cross a city boundary to commute, making it potentially more convenient to put their children to a daycare center close to their workplace"

Japanese court upholds ban on same sex marriage

 The Japan Times has the story:

In LGBTQ rights setback, Japan court says barring same-sex marriage not unconstitutional   June 20, 2022

"An Osaka court on Monday ruled that Japan's ban on same-sex marriage was not unconstitutional, dealing a blow to LGBTQ rights activists in the only Group of Seven nation that doesn't allow people of the same gender to marry.

"Three same-sex couples — two male, one female — had filed the case with the Osaka District Court, only the second case to be heard on the issue in Japan. In addition to rejecting their claim that being unable to marry was unconstitutional, the court dismissed their claim for ¥1 million per person in damages.

"The plaintiffs said they will appeal Monday's ruling to a higher court.

"The latest case revolved around the interpretation of marriage in Article 24 of the Constitution, which stipulates, "Marriage shall be based only on the mutual consent of both sexes and it shall be maintained through mutual cooperation with the equal rights of husband and wife as a basis."

Market design in Tokyo

 Fuhito Kojima and Hiroaki Odahara report on some of the projects presently underway at the University of Tokyo Market Design Center (UTMD), which include matching for child care, for medical residencies, and for internal labor markets.

Kojima, F., Odahara, H. Toward market design in practice: a progress report. Japanese Economic Review, (2021). https://doi.org/10.1007/s42973-021-00103-w

Abstract: In recent years, many developments have been made in matching theory and its applications to market design. This paper surveys some selected topics from this research area and describe our own work. We also describe the newly established University of Tokyo Market Design Center (UTMD), which works as a vehicle for practical implementation.

Fuhito Kojima and I will discuss improving social welfare with matching theory in a Nikkei Business webinar this evening

Fuhito Kojima and I will participate in a Nikkei Business Zoom webinar on The Future of Management 2030, in English and Japanese (I think translation will be available).

 "Nikkei Business LIVE will hold a webinar entitled "The Future of Management 2030: Rebuilding Capitalism and Revitalizing Innovation" for three days from October 5th to 7th. 

Our discussion, on "Creating a better society by implementing matching theory" will be at 11AM tomorrow in Japan (which is 7PM this evening in California).

"Creating a better society by implementing matching theory in society"

"Auction theory that was in the limelight at the 2020 Nobel Prize in Economics. It is one of the theories representing the new field of microeconomics, "market design," which seeks to design a market in which traders can satisfy each other, rather than analyzing the existing market as in the past. The pioneer who won the Nobel Prize in Economics for "market design" is "matching theory" by Professor Alvin Roth and others. He talks with Professor Fuhito Kojima of the University of Tokyo Graduate School of Economics, who is a direct pupil and a former colleague at Stanford University, about the future brought about by the social implementation of economic theory." (via Google translate)

Lectures on equilibrium in markets for indivisible goods at U. Tokyo by Teytelboym, Baldwin and Jagadeesan, Sept 21-24

 Towards a general theory of markets with indivisible goods: special lectures at The University of Tokyo Market Design Center (UTMD)

September 21-24, 2021 (Japan time) 

Organizers:

Fuhito Kojma, Director, UTokyo Market Design Center, and Professor, the University of Tokyo

Michihiro Kandori: Vice Director, UTokyo Market Design Center, and University Professor, the University of Tokyo

Yuichiro Kamada: Associate Professor, UC Berkeley, and Global Fellow, the University of Tokyo

Venue: Zoom online  Language: English

Program

*All times shown below are Japan time.

*Each lecture will be followed by 30 minutes Q&A session.

Lecture 1 9/21 (Tue) 16:00-17:30

Introduction to Markets for Indivisible Goods (by Alexander Teytelboym)

In many settings, such as auctions, the indivisibility of goods is a key market feature. But in markets with indivisible goods, competitive equilibria might not exist.  We explore conditions, such as substitutability of goods, that ensure existence of competitive equilibria. We also discuss connections between conditions for existence, tâtonnement, and cooperative properties of equilibria.

Lecture 2 9/22 (Wed) 16:00-17:30

The geometry of preferences: demand types, equilibrium with Indivisibilities, and bidding languages (by Elizabeth Baldwin)

An equivalence theorem between geometric structures and utility functions allows new methods for understanding preferences. Our classification of valuations into “Demand Types”, incorporates existing definitions regarding the comparative statics of demand (substitutes, complements, “strong substitutes”, etc.) and permits new ones. Our Unimodularity Theorem generalises previous results about when competitive equilibrium exists for any set of agents whose valuations are all of a “demand type”. Contrary to popular belief, equilibrium is guaranteed for more classes of purely-complements, than of purely-substitutes, preferences. Our Intersection Count Theorem checks equilibrium existence for combinations of agents with specific valuations by counting the intersection points of geometric objects. Applications include the “Product-Mix Auction” introduced by the Bank of England in response to the financial crisis. In that context, we show that all substitutes preferences can be represented, and no other preferences can be represented, by appropriate sets of permitted bids in the Substitutes Product-Mix Auction language; an analogous result holds for strong substitutes, when we refine the characteristics of the language. These languages thus also provide new characterizations of (all) substitutes, and of strong substitutes, respectively.

Lecture 3 9/23 (Thu) 16:00-17:30 The Equilibrium Existence Duality (by Alexander Teytelboym)

We show that, with indivisible goods, the existence of competitive equilibrium fundamentally depends on agents’ substitution effects, not their income effects. Our Equilibrium Existence Duality allows us to transport results on the existence of competitive equilibrium from settings with transferable utility to settings with income effects. One consequence is that net substitutability—which is a strictly weaker condition than gross substitutability—is sufficient for the existence of competitive equilibrium. Further applications give new existence results beyond the case of (net) substitutes. Our results have implications for auction design.

Lecture 4 9/24 (Fri) 09:30-11:00 Matching and Prices (by Ravi Jagadeesan)

Indivisibilities and budget constraints are pervasive features of many matching markets. But gross substitutability — a standard condition on preferences in matching models — typically fails in such markets. To accommodate budget constraints and other income effects, we instead assume that agents’ preferences satisfy net substitutability. Although competitive equilibria do not generally exist in our setting, we show that stable outcomes always exist and are efficient. We illustrate how the flexibility of prices is critical for our results. We also discuss how budget constraints and other income effects affect the properties of standard auction and matching procedures, as well as of the set of stable outcomes.

  Recorded lecture will be posted on UTMD’s YouTube channel within 6 hours.

 

Uterus transplants considered in Japan

 Here's the story from the Asahi Shimbun, including some background. For the time being, only living-donor organs seem to be allowed under Japanese law:

Medical group allows for uterus transplants to give birth

"A Japanese Association of Medical Sciences committee released a report on July 14 clearing the way for uterus transplants, a rare procedure that faces obstacles. 

...

"The biggest issue facing the committee was that the transplant objective would be to allow the woman to give birth.

"That differs greatly from other transplants in which the main objective is to save the recipient’s life. In addition, committee members had to consider allowing a transplant operation that held major health risks for both the donor and recipient.

"According to a report, there have been 85 cases of uterus transplants in 16 nations overseas as of March and 40 have led to the delivery of a baby.

"In many of those cases, an in-vitro fertilized embryo is placed in the transplanted uterus. But the uterus is removed after childbirth because of the need to continue using immunosuppressant agents to prevent the body from rejecting the transplanted organ.

"In Japan, there are an estimated 60,000 to 70,000 women between the ages of 20 and 50 who were born without uteruses or have had their uteruses surgically removed due to tumors or other causes.

...

"There are also legal hurdles that have to be cleared.

"Japan’s organ transplant law does not include uteruses as an organ that can be removed for transplantation from a brain-dead individual.

"For that reason, the report allowed for transplants from live donors in only a very few cases to conduct clinical research.

"The report also called for revising the organ transplant law to allow for uterus transplants from brain-dead women.

"But even if the law was revised, organ donations from brain-dead individuals are still not widespread in Japan, meaning it would be almost impossible to plan for a uterus transplant operation.

"Experts were divided in their views about the latest report.

"Nobuhiko Suganuma, a professor of reproductive medicine at Nagoya University of Arts and Sciences who heads the Japan Society for Uterus Transplantation, said providing an alternative for women who want to give birth was a positive development.

"But Yukiko Saito, an associate professor of medical ethics at Kitasato University, raised concerns about approving an available technology just because there may be people who want to utilize it."

Same sex marriage in Japan takes a step forward

In The U.S., court decisions paved the way for same sex marriage.  Now there's a court decision in Japan. The NY Times has the story:

Landmark Ruling Cracks Door Open for Same-Sex Marriage in Japan. A court found that it was unconstitutional for the country not to recognize the unions. But change would come only if Parliament passes legislation. By Ben Dooley and Hisako Ueno

"A Japanese court on Wednesday ruled that the country’s failure to recognize same-sex marriages was unconstitutional, a landmark decision that could be an important step toward legalizing the unions across the nation.

"The ruling, handed down by a district court in the northern city of Sapporo, came in a civil suit against the Japanese government by three same-sex couples. 

...

"The ruling will not, however, change the law. Same-sex marriages will be recognized in Japan only if Parliament enacts legislation, Mr. Dmitrenko said. Lawmakers have repeatedly declined to take up such a bill.

"Still, activists saw the court’s decision as an important step in tearing down barriers to normalizing gay marriage in Japan, the only country in the Group of 7 nations that has not legalized same-sex unions.

"The unions are not explicitly banned in Japan, but they are not recognized by the national government or most localities. In recent years, some local governments have moved to provide gay couples with certificates acknowledging their marriage, but the documents have little legal or practical value.

"National authorities have long argued that their position is supported by a provision in the country’s constitution that stipulates marriage can occur only with the consent of both sexes, a provision that was intended to stop Japan’s once common practice of arranged marriages."

Regulating the timing of job search: evidence from the labor market for new college graduates, by Hiroko Okudaira

 

Regulating the timing of job search: evidence from the labor market for new college graduates

Hiroko Okudaira, Doshisha University, Labour Economics, Volume 67, December 2020, 101941

Abstract: In entry-level labor markets, students search for post-graduation positions well in advance of their actual start dates, prompting debates over regulating job search timing. This study examines a unique case concerning the new college graduate labor market in Japan, where a guideline revision successfully delayed the timing of job searches and forced market participants to search under a shorter horizon. Based on differential exposures to the guideline revision across regions, I find that the revision significantly increased the employment rate at graduation. No positive effect was observed on students’ human capital investment. Additional analyses offers one plausible interpretation, that the positive employment effect was driven by thick market externality.

"This paper provides the first evidence on the consequences of regulating job search timing by exploiting the unique case of the new college graduate job market in Japan, where a guideline revision successfully delayed search timing and forced market participants to search under a shorter horizon. 

...

"By 2009, the job search timing advanced to the middle of the junior year, nearly 18 months prior to graduation. In 2010, the biggest business association announced it would revise the guideline and establish a job search start date for the first time since its introduction. 

...

"Unlike previous cases, however, the revision successfully delayed the overall timing due to the closure of a popular online platform until the first date specified in the revision. Because college students start communicating with firms’ personnel via these online platforms by registering for first-step seminars and because these online platforms were so dominant, the market was diluted substantially in that much fewer firms and students were available in the market prior to the first date.

***********

Xiaolin Xing and I included some of the unsuccessful attempts to control the timing of the college graduate market in Japan in 

Roth, A.E. and X. Xing, "Jumping the Gun: Imperfections and Institutions Related to the Timing of Market Transactions," American Economic Review, 84, September, 1994, 992-1044

Assisted reproductive technology in Japan's national health insurance

 The Financial Times has the story:

Prime minister floats fertility treatment to boost Japan’s birth rate--Critics say making IVF cheaper will not address economic insecurity of raising children by Robin Harding

"Japan has spent 50 years fretting about its low birth rate and declining population but new prime minister Yoshihide Suga has hit on a different solution: fertility treatment.

"In his leadership campaign, Mr Suga called for in vitro fertilisation to be covered on national health insurance. The prime minister wants to make it affordable in a country where the average age of first-time mothers is now above 30 and nearly one in five couples has had tests or treatment for infertility.

"Mr Suga hopes the policy will raise Japan’s fertility rate, which stood at 1.36 children per woman in 2019. The fertility rate has been below the replacement level of 2.1 since the 1970s, locking in decades of future population decline with profound consequences for Japan’s society, economy and national security.

"But while subsidies for fertility treatment reflect a slow shift in Japan towards supporting parents rather than criticising the childless, experts said it still did little to address the economic insecurity and gender inequality that discouraged marriage and raising children."

Interviews with Fuhito Kojima, Bob Wilson, and Al Roth in the Japanese economic magazine Diamond Weekly

 Here are three interviews conducted by the journalist Kohei Takeda for the Japanese economic magazine  DIAMOND WEEKLY, on their website DIAMOND ONLINE.   

Here are the headlines and beginnings via Google Translate.

The essence of the Nobel Prize in Economics "Game Theory", explained by a former colleague of the award winner--Interview with Fuhito Kojima, Professor of the University of Tokyo, Director of Market Design Center, University of Tokyo  by Kohei Takeda : Reporter

The interview begins with these opening words from Fuhito:

"Eight years ago, when Al (Professor at Alvin Roth Stanford University), who I had been taught, received the award, we held a grand celebration and press conference. I thought I couldn't do that this year due to the spread of the new coronavirus infection, but in the evening of the award day (October 12), planned by him and his wife Emily, in the garden of Al's house. A small celebration was held while keeping a certain distance from each other.

"At universities in the United States, teachers and students tend to live very close to the campus, so fellow researchers have more relationships with their neighbors. I still lived near the university, so I received an invitation email from Emily on the day and participated in the celebration. ...

"To me, Paul was a colleague at the university, but he is also like a mentor. After I got a job at Stanford University about 10 years ago, my research field was the same "market design" in the Faculty of Economics (Editor's note: one of the research fields of game theory) , and sometimes I wrote a co-authored paper. , I was able to build a good relationship.

"He is a major researcher I have known since I was a student... Bob taught both Al and Paul, so academically I'm also Bob's "grandson."

************

2020 Nobel Prize Winner "Auction Theory for Business" Special Lecture--Interview with Professor Emeritus of Robert Wilson Stanford University by Kohei Takeda : Reporter

The first thing Bob was asked to explain was his work on the winner's curse:

"I started working in this area in the 1960s. The background to this was the issue of oil drilling rights among US oil companies at that time. They had very incomplete information about what their oil reserves were. From the size of the oil field to whether or not it was filled with hydrocarbons, there were many things we didn't know. Oil companies were under pressure to estimate their reserves in such an unknown environment.

"When auctioning under these circumstances, each participating player tends to overestimate in order to win the bid. In this case, each estimate is a function to increase the likelihood of bidding, but oil companies face the challenge of significantly lower rates of return after investing in oil rigs. Was there.

"Eventually, this is (in a situation where each player does not have the same information, the information is asymmetrical, and the player eventually chooses the less valuable one in an attempt to maximize his or her profits). (Adverse selection) ”was recognized as a problem. In other words, there was a tendency to win bids only when overestimating.

"What I have built is a theory for bidding various things in the best possible way, taking into account the situation of such adverse selection. This achievement has attracted a great deal of attention and is one of my early achievements in research. The negative effect of overestimating what is being bid on and winning the auction has been called "Winner's Curse". However, the best bidding strategy takes its existence into account, so you won't suffer from the curse of the winner."

***********

Nobel laureate in economics "Matching theory that can be used in business" --Interview with Professor Alvin Roth Stanford University by Kohei Takeda : Reporter

Fuhito Kojima wins the 2021 Japanese Economic Association Nakahara Prize

 Congratulations to Fuhito Kojima, who is the 2021 winner of the Nakahara Prize of the Japanese Economic Association, which is awarded each year to an exceptional economist under the age of 45.

You can find the announcement (in Japanese) here. Google translate works well, and you can see the list of previous winners.

Here's part of the English announcement (which I can't find on the web...)

"The 2021 Japanese Economic Association Nakahara Prize

Professor Fuhito Kojima

"The Nakahara prize was established in 1995 and is funded by a donation from Mr. Nobuyuki Nakahara. The aim of the prize is to honor and encourage young researchers under the age of 45 to publish internationally recognized research. 

It is a great pleasure to announce that the 2021 Nakahara prize has been awarded to Professor Fuhito Kojima. Born in 1979, Professor Kojima received BA in economics from the University of Tokyo, and earned Ph.D. in economics from Harvard University in 2008. He was Assistant, Associate and then Full Professor of Economics at Stanford University, and he is Professor of Economics at the University of Tokyo from September 2020.

Professor Kojima’s research is focused on matching theory and market design. He has made a number of important contributions to the field. Many of his researches are motivated by various kinds of constraints imposed on matching problems in real life. His research significantly contributes to widening applicability of the theory to real matching markets.

...

"Selected Publications

1. “Job Matching under Constraints” (2020), joint with Ning Sun and Ning Neil Yu,  conditionally accepted, American Economic Review.

2. “Stable Matching in Large Economies” (2019), with Yeon-Koo Che and Jinwoo Kim, Econometrica, 87-1, pp65-110.

3. “Efficient Matching Under Distributional Constraints: Theory and Applications” (2015), with Yuichiro Kamada, American Economic Review, 105, pp 67-99.

4. “Matching with Couples: Stability and Incentives in Large Matching Markets” (2013), with Parag A. Pathak and Alvin E. Roth, Quarterly Journal of Economics 128, pp 1585-1632.

5. “Designing Random Allocation Mechanisms: Theory and Applications” (2013), with Eric Budish, Yeon-Koo Che, and Paul Milgrom, American Economic Review 103, pp 585-623.

6. “Asymptotic Equivalence of Probabilistic Serial and Random Priority Mechanisms” (2010), with Yeon-Koo Che, Econometrica 78, pp 1625-1672.

7. “Axioms for Deferred Acceptance” (2010), with Mihai Manea, Econometrica 78, pp 633-653.

8. “Incentives and Stability in Large Two-Sided Matching Markets” (2009), with Parag A. Pathak, American Economic Review 99, pp 608-27.

SELECTION COMMITTEE

Kosuke Aoki (Chair) (University of Tokyo), Anton Braun (Federal Reserve Bank of Atlanta), Federico Echenique (California Institute of Technology), Yuichi Kitamura (Yale University), Fumio Ohtake (Osaka University), Tadashi Sekiguchi (Kyoto University), Mototsugu Shintani (University of Tokyo)

************

By a strange coincidence,  in 2013 I was the recipient of a non-academic award signed by Mr. Nobuyuki Nakahara, whose interests extend beyond economics.

Speed dating, and matchmaking via Zoom, in Japan

The Washington Post has the story:

Lockdowns make the heart grow fonder in Japan as online matchmaking surges
By Simon Denyer and Akiko Kashiwagi   July 12, 2020

"Online matchmaking in Japan has become a rare upbeat counterpoint to the economic slowdowns, shutdowns and restrictions during the covid-19 crisis.

"Matchmaking agencies say the video encounters have proved to be a hit, removing the pressures of arranged face-to-face sessions in a society that often discourages being bold and open in first meetings.
...
"LMO and other companies tend to start with a group meeting conducted over Zoom: An emcee makes everyone comfortable, helps them introduce themselves and asks them a few questions to spark conversation. How have you been being spending your time at home? How do you imagine married life to be? What are your dreams? Then participants pair off into breakout rooms and spend several minutes chatting to each prospective partner in turn."

School choice, centralized and decentralized, in Japan, a century ago, by Tanaka, Narita and Moriguchi

I heard Yusuke Narita present this remarkable paper comparing centralized and decentralized school matching at a recent seminar at Stanford.  It uses a  data set involving both outcomes and rules (rules are data!) of a school choice system for elite schools in Japan from the turn of the last century

Meritocracy and Its Discontent: Long-run Effects of Repeated School Admission Reforms
 TANAKA, Mari  NARITA, Yusuke  MORIGUCHI, Chiaki

Abstract: "We study the impacts of changing school admissions systems in higher education. To do so, we take advantage of the world’s first known implementation of nationally centralized admissions and its subsequent reversals in early twentieth-century Japan. This centralization was designed to make admissions more meritocratic, but we find that meritocracy came at the cost of threatening equal regional access to higher education and career advancement. Specifically, in the short run, the meritocratic centralization led students to make more inter-regional and risk-taking applications. As high ability students were located disproportionately in urban areas, however, increased regional mobility caused urban applicants to supplant rural applicants from higher education. Moreover, these impacts were persistent: four decades later, compared to the decentralized system, the centralized system continued to increase the number of urban-born elites (e.g., top income earners) relative to rural-born ones.

" Our empirical setting is the first known transition from decentralized to nationally centralized school admissions. At the end of the 19th century, to modernize its higher education system, the Japanese government set up elite national schools (high schools or colleges) that served as an exclusive entry point to the most prestigious tertiary education (Yoshino, 2001a,b; Takeuchi, 2011). These schools later produced many of the most influential members of the society, including several Prime Ministers, Nobel Laureates, and founders of global companies like Toyota. Acceptance into these schools was merit-based, using annual entrance examinations. Initially, the government let each school run its own exam and admissions based on exam scores, similar to many of today’s decentralized K-12 and college admissions. The schools typically held exams on the same day so that each applicant could apply for only one school. Similar restrictions on the number of applications exist today in the college admission systems of Italy, Japan, Nigeria, and the UK.

"At the turn of the 20th century, the government introduced a centralized system in order to improve the quality of incoming students. In the new system, applicants were allowed to rank multiple schools in the order of their preference and take a single unified exam.1 Given their preferences and exam scores, each applicant is assigned to a school (or none if unsuccessful) based on a computational algorithm. The algorithm was a mix of the so called Immediate Acceptance (Boston) algorithm and Deferred Acceptance algorithm with a meritocracy principle imposed upfront. To the best of our knowledge, this instance is the first recorded, nation-wide use of any matching algorithm. Furthermore, for reasons detailed below, the government later re-decentralized and re-centralized the system several times, producing multiple natural experiments for studying the consequences of the different systems."

Sex related businesses in Japan

Japan is complicated. Here's a story from the Guardian that seems not to involve prostitution, but is nevertheless sex related (and child related).

Schoolgirls for sale: why Tokyo struggles to stop the 'JK business'
The persistent practice of paying underage girls for sex-related services, known in Japan as the ‘JK’ business, has seen charities step in where police have come up short

"Tokyo is famous for its fairly wild red light scene. You can find anything from a handsome man to make you cry and wipe away your tears to a maid to pour your drinks and giggle at your jokes and an encounter in one of the notorious “soapland” brothels.

"You can also pay to spend time with a schoolgirl. Services might include a chat over a cup of tea, a walk in the park or perhaps a photograph – with some places offering rather more intimate options.
...
"The fetishisation of Japanese schoolgirls in Japanese culture has been linked by some academics to a 1985 song called Please Don’t Take Off My School Uniform, released by the female idol group O-nyanko Club, and re-released by no less mainstream a group than AKB48, one of the highest-earning musical performers in Japan and whose single Teacher Teacher sold more than 3m copies in 2018.

"The term “JK business” has become a catch-all for cafes, shops and online agencies which provide a range of “activities”, many of which are not overtly sexual. Young women in school uniforms can be offered for reflexology and massage treatments, photography sessions and “workshops” in which girls reveal glimpses of their underwear as they sit folding origami or creating jewellery.
...
"Japan’s anti-prostitution laws broadly prohibit the sale and purchase of sex, but there are significant loopholes, of which establishments such as soaplands take full advantage. Crucially, in the case of JK businesses, Japan has no specific anti-trafficking laws in place. Ordinarily, a child under 18 involved in sex work is automatically considered trafficked, with harsh penalties for those responsible.

"Pornography laws relating to children are also limited – they do not, for example, cover manga, anime, or virtually created content, allowing games such as 2006’s controversial (and now no longer available) RapeLay, in which the player stalks and attempts to rape a single mother and her two school-age daughters."

Repugnant phrasing

Japan's labor and immigration policies have been more restrictive than welcoming to an immigrant/migrant labor force.  So one can imagine a cheerful headline saying that was about to change, something along the lines of the final paragraph quoted below.  I don't think the following WSJ headline quite does the trick:

Japan Aims to Hire Foreigners for Nuclear Cleanup
The country’s largest utility is working to decommission the Fukushima plant amid radiation risks at the site of the 2011 disaster

"TOKYO—Japan’s largest utility is looking to foreign blue-collar workers to help decommission its Fukushima Daiichi nuclear-power plant amid a labor shortage exacerbated by radiation risks at the site of the 2011 nuclear disaster.

"Tokyo Electric Power Co. , or Tepco, said Thursday it has informed dozens of contractors that foreigners could qualify for a new type of visa that allows manual workers to stay in the country for five years. Workers who enter areas with elevated radiation would need sufficient Japanese-language skills to comprehend radiation levels and safety instructions, a Tepco spokeswoman said.

"The move is a shift in strategy for Tepco, which hasn’t employed large numbers of blue-collar foreigners at the Fukushima plant. As of February, there were 29 foreign workers, the spokeswoman said.

"Under a new law that went into effect this month, Japan plans to open its doors to about 340,000 workers over the next five years to help fill job vacancies in chronically understaffed industries such as construction and nursing care. The new law also creates another type of visa for higher-skilled blue-collar workers who can stay indefinitely."

Japan's health insurance will pay for overseas transplants

In Japan, the national insurance will now pay for some transplants done overseas, when they cannot be done at home. The discussion reflects concern that they may be accused of organ trafficking. (Thanks to Fuhito Kojima for the link...)

海外臓器移植、一部保険給付へ　１千万円程度　現在は全額自己負担

(Google translate: Overseas organ transplantation, partial insurance benefit To ten million yen now All costs self-burden)  http://www.sankei.com/politics/news/171212/plt1712120018-n1.html

"Katsuobu Kato Kunihiro Kato revealed a policy to pay part of expenses from public health insurance to patients who are going abroad and get organ transplants because they are not provided domestically at the Cabinet meeting after the Cabinet meeting on December 12 . Consider using "overseas medical care expense system" to reimburse overseas treatment expenses from medical insurance of subscribers. The relevant patient seems to be around ten people a year, mainly children.

　"Currently, all overseas organ transplant patients are borne entirely by themselves, and in the case of the heart, since it costs several hundred million yen, there are many cases where fund raising activities are carried out. There is also an international declaration that "Organs necessary for transplant surgery should be secured in the home country", and this policy can lead to promotion of transplantation and international criticism is also anticipated. Kato Atsushi said, "It is fundamental to implement organ transplants under the domestic regime and it will not change anything."

　"The subjects to be covered by insurance are limited to patients who satisfy certain criteria such as being registered in the Japan Organ Transplant Network and being in danger of maintaining life in the standby state. When applying for overseas medical expenses, it is also necessary to prove that it is an operation not applicable to organ trafficking."
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 I'm reminded of current controversies concerning global kidney exchange, which involves cross-border kidney exchange.

Organ donation and transplantation in Japan

The Chicago Tribune has an article (reprinted/translated?) from Japan:
Japan badly lags world in organ transplants
Yukiko Takanashi and Sakae Sasaki, (c) 2016, The Japan News/Yomiuri
(c) 2016, The Japan News/Yomiuri

"In July 2010, the revised Organ Transplant Law came into effect, enabling organ donations after the brain death of children younger than 15. However, there have been only 12 cases of organ donation by children under 15 since then. According to the Japanese Society for Heart Transplantation, 29 Japanese children under 18 traveled abroad for a transplant between 2010 and June 2016. That is more than twice the number that received a donor organ in Japan.

...

"In 2015, the organ donation rate in Japan stood at 0.7 people per million people. Spain had the highest rate at 39.7 people per million. The gap between Japan and other major countries remains wide. The rate stood at 28.5 people per million people in the United States, 27.5 in France, and 20.2 in Britain.

...

"The so-called Wada transplant, said to be Japan's first transplant from a brain-dead donor, was conducted in 1968 by Juro Wada at Sapporo Medical University. The boy who received the donor's heart died, and Wada was charged with murder. Questions were raised as to whether the organ donor had really been brain dead, and the case stirred a major controversy over the definition of death. For more than 30 years after that, no transplants from brain-dead donors were performed in Japan."
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Deutsche Welle has a related story:
Why organ transplant is so difficult to carry out in Japan
Restrictive laws, religious concerns and a lack of knowledge about donating organs mean that medically-sophisticated Japan lags well behind other nations in life-saving operations. Julian Ryall reports from Tokyo.

Market design and cultural context: from an interview in Japan

When I was in Japan in April I spoke at Tokyo Institute of Technology. Here's a brief account that just appeared in English, highlighting some remarks I made that markets have cultural contexts: Professor Alvin E. Roth interviewed in Contemporary Society class

"A student asked why Roth engages in fieldwork such as operating room visits to conduct his research. The professor pointed out that markets have too many unwritten rules and are too complex to understand only through books. There are also many culture-related rules that need to be learned through direct experience. If someone designs the Japanese market, that person should be Japanese, someone who truly understands Japanese culture. This comment visibly moved the audience and will undoubtedly motivate students as they pursue their future study and research activities."