Wednesday, March 4, 2020

Can YouTube's recommender engine tone down conspiracy theories?

The NY Times has the story:

Can YouTube Quiet Its Conspiracy Theorists?
A new study examines YouTube’s efforts to limit the spread of conspiracy theories on its site, from videos claiming the end times are near to those questioning climate change. By Jack Nicas

"In January 2019, YouTube said it would limit the spread of videos “that could misinform users in harmful ways.”

"One year later, YouTube recommends conspiracy theories far less than before. But its progress has been uneven and it continues to advance certain types of fabrications, according to a new study from researchers at University of California, Berkeley.

"YouTube’s efforts to curb conspiracy theories pose a major test of Silicon Valley’s ability to combat misinformation, particularly ahead of this year’s elections. The study, which examined eight million recommendations over 15 months, provides one of the clearest pictures yet of that fight, and the mixed findings show how challenging the issue remains for tech companies like Google, Facebook and Twitter."
***********

The paper referred to seems to be this one on Hany Farid's website at Berkeley. It's very recent ("compiled on March 2, 2020," the day of the NY Times story, and e.g. it finds that corona virus conspiracy videos are not being recommended despite being readily available). 

A longitudinal analysis of YouTube’s promotion of conspiracy videos
Marc Faddoul, Guillaume Chaslot, and Hany Farid


Abstract: Conspiracy  theories  have  flourished  on  social  media,  raising  concerns that such content is fueling the spread of disinformation, sup-porting extremist ideologies, and in some cases, leading to violence. Under increased scrutiny and pressure from legislators and the public, YouTube announced efforts to change their recommendation algorithms so that the most egregious conspiracy videos are demoted and demonetized.  To verify this claim, we have developed a classifier for automatically determining if a video is conspiratorial (e.g., the moon landing was faked, the pyramids of Giza were built by aliens, end of the world prophecies, etc.). We coupled this classifier with an emulation of YouTube’s watch-next algorithm on more than a thousand popular informational channels to obtain a year-long picture of the videos actively promoted by YouTube.  We also obtained trends of the so-called filter-bubble effect for conspiracy theories



And here are the concluding paragraphs:


"Summary. The overall reduction of conspiratorial recommendations is an encouraging trend. Nonetheless, this reduction does not make the problem of radicalization on YouTube obsolete nor fictional, as some have claimed (41). Aggregatedata hide very different realities for individuals, and although radicalization is a serious issue, it is only relevant for a fraction of the users. Those with a history of watching conspiratorial content can certainly still experience YouTube as filter-bubble, reinforced by personalized recommendations and channel subscriptions. In general, radicalization is a more complex problem than what an analysis of default recommendations cans cope, for it involves the unique mindset and viewing patternsof a user interacting over time with an opaque multi-layer neural network tasked to pick personalized suggestions from a dynamic and virtually infinite pool of ideas.


"With two billion monthly active users on YouTube, the design of the recommendation algorithm has more impact on the flow of information than the editorial boards of traditional media. The role of this engine is made even more crucial in the light of (1) The increasing use of YouTube as a primary source of information, particularly among the youth (42); (2)The nearly monopolistic position of YouTube on its market;and (3) The ever-growing weaponization of YouTube to spread disinformation and partisan content around the world (43). And yet, the decisions made by the recommendation engine are largely unsupervised and opaque to the public.


"This research is an effort to make the behavior of the algorithm more transparent, in an effort to increase the awarenessof the public and YouTube’s accountability for their statements. We hope it will fuel a public discussion, not about whether YouTube should allow for conspiratorial content on the platform, but about whether such content is appropriate to be part of the baseline recommendations on the informational YouTube.

Tuesday, March 3, 2020

Kidney exchange at the 34th Advanced HLA Technical Workshop


I'll be speaking tomorrow morning, March 4, at the 34th Advanced HLA Technical Workshop,  at the Omni Rancho Las Palmas Resort in Rancho Mirage, California.  These are the folks who (among other things) figure out if a kidney donor and patient are compatible, so that the patient can be transplanted with a kidney from that donor.

Here is the conference Agenda.

My session is
Advancing Transplantation
9:00 AM-10:00 AM
Moderator:
Cathi Murphey-Half, PhD
Southwest Immunodiagnostics - San Antonio, TX

Speaker:
Kidney Exchange: Past, Present and Possible Future
Alvin E. Roth, PhD
Stanford University - Stanford, CA



When I talk about the detailed compatibility aspects of matching for kidney exchange, I'll be able to describe the current state of the art. Here's my first slide on that:


Monday, March 2, 2020

NSF 70th Anniversary Symposium--the video

I recently attended the celebration of the 70th anniversary of the National Science Foundation, a two-day symposium on Feb. 6-7, 2020. Below is a video of the first day, in which I took part in a session called Science Breakthroughs, which begins at hour 3:45 and goes for an hour. Hear a moderated discussion ranging back and forth over gravity waves, black holes, thermal vents, nanotechnology, and market design (school choice, kidney exchange, repugnant transactions and the fact that both markets and bans on markets require social support to work well).




Science Breakthroughs
Panel featuring NSF-funded science breakthroughs from the last decade. The topics covered in this panel will feature a mix of major breakthroughs, as well as research that has led to significant impacts on society. In addition, the panelists will be a diverse set of researchers, including those earlier in their careers.

Moderator: Amy Harmon, Correspondent, New York Times
Panelists: Jennifer Dionne, 2019 Waterman Award recipient & Associate Professor, Stanford University
Shep Doeleman, 2019 Breakthrough Prize & NSF Diamond Award recipient & Director, EHT at Harvard-Smithsonian Center for Astrophysics
Margaret Leinen, Director, Scripps Institute & Vice Chancellor & Dean, Marine Sciences
Nergis Mavalvala, Professor & Associate Head, Department of Physics, MIT
Alvin Roth, Nobel Prize in Economics 2012 & Professor of Economics, Stanford University



Sunday, March 1, 2020

Don't need no education -- arguments about California propositions to raise revenue for community colleges

I'm spending part of the day perusing the California ballot for Tuesday's elections, which include not only the widely anticipated, contested Democratic presidential primary, but also some voter referenda.  In Santa Clara County, where I live, there are two measures on the ballot, G and H, aimed at raising revenue for our highly regarded community colleges.  Measure G proposes issuing bonds (to be supported by property taxes), and H proposes a direct property tax levy.  The County issues a voter information guide which publishes the text of the measures, together with statements by interested parties both for and against the measures, with rebuttals.

Here is a paragraph that caught my eye from the REBUTTAL TO ARGUMENT IN FAVOR OF MEASURE H* submitted by an organization calling itself  Silicon Valley Taxpayers Association.

"Voters in this district are not fools. But voters in richer districts tend to approve tax increases without insufficient analysis."


*this can be found on N SC Ballot Type 001 - Page 024, which is page 26/44 of the pdf at the link to the information guide.

The oldest extant companies in the world

Old companies are interesting, especially given the view that (short term) profit maximization isn't the only thing that companies might think about.

Here's a map from twisted sifter: you can click on it to zoom in:
The Oldest Company in (almost) Every Country
*that is still in business

For the U.S. they list Shirley Plantation as in operation since 1638 (whereas the home page at the link says "Est. 1613)
"Shirley Plantation is America’s oldest farm and family-owned business and is lived in and actively managed by direct descendants of the original builders."

You could stay at Gasthof Sternen in Zurich (opened in 1230)

The Paris Mint, Monnais de Paris (864) describes itself as
"France's longest standing institution and the oldest enterprise in the world, Monnaie de Paris was officially founded in 864 with the Edict of Pistres. In the Edict, Charles II - known as Charles the Bald - decreed the creation of a coining workshop in Paris, attached to the crown"

And then there's Kongo-Gumi in Japan, founded in 578 (and now part of the Takamatsu Construction Group).

Saturday, February 29, 2020

The 1918 influenza pandemic

Communications failures played a role in the 1918 pandemic:

A flu that brought nations to a standstill  Jennifer A. Summers

"The year was 1918 and after four grisly years of the First World War, the longed-for peace was within the grasp of the Allied powers. But little did they know, that a threat far greater than any war experienced by humans loomed over their existence.

"An influenza virus, minute in size, was slowly making its presence felt. Fuelled by the unprecedented movement of troops worldwide, it spread to almost every corner of the globe.

"The symptoms of this influenza were particularly gruesome. ...

"Wartime censorship held a firm grip on influenza reports at the time, as military authorities speculated that the gas-soaked trenches and horrific conditions of the Western Front were somehow responsible. Civilians were therefore left in the dark about the approaching pandemic. Indeed, its common name ‘Spanish Flu’ is a reference to neutral Spain being the first country in the world to report its existence officially to its citizens."

Friday, February 28, 2020

Regretting the dating market, in the Atlantic

In the Atlantic, the authors regret that marriages are no longer made in heaven, but are becoming a market...

The ‘Dating Market’ Is Getting Worse
The old but newly popular notion that one’s love life can be analyzed like an economy is flawed—and it’s ruining romance. by ASHLEY FETTERS and KAITLYN TIFFANY

Many people are quoted, most briefly and to the effect that the marriage market is a new and bad phenomenon.

"The application of the supply-and-demand concept, Weigel said, may have come into the picture in the late 19th century, when American cities were exploding in population. “There were probably, like, five people your age in [your hometown],” she told me. “Then you move to the city because you need to make more money and help support your family, and you’d see hundreds of people every day.” When there are bigger numbers of potential partners in play, she said, it’s much more likely that people will begin to think about dating in terms of probabilities and odds."

I seem to have been the only one who didn't have a negative quote about markets (in an interview that if I recall correctly took place on Valentine's day):

"The Stanford economist Alvin Roth has argued that Tinder is, like the New York Stock Exchange, a “thick” market where lots of people are trying to complete transactions, and that the main problem with dating apps is simply congestion. To him, the idea of a dating market is not new at all. “Have you ever read any of the novels of Jane Austen?” he asked. “Pride and Prejudice is a very market-oriented novel. Balls were the internet of the day. You went and showed yourself off.”

Thursday, February 27, 2020

Proposal to decriminalize polygamy in Utah

Marriage is special, a protected transaction in the U.S. and elsewhere, and that has led to odd situations as social mores change.  Same sex marriage is now legal in every U.S. state, but long before that happened, laws against homosexual sex had already been repealed. So same sex couples were able to live peacefully together before they could marry.*

In much the same way, it is not a crime in most places for unmarried people to live together, and start families.  The phrase 'polyamory' is sometimes applied to romantic relations among multiple adults.  But marriage, no longer defined as a relation between one man and one woman, is still defined as a relation between two people (but now they can also be of the same sex).  That "two-ness" may be starting to change too.

The WSJ has the story:

Utah Lawmakers Seek to Decriminalize Polygamy
Sponsor says bill will help ‘otherwise law-abiding consenting adults who practice polygamy’
By Talal Ansari

"Utah could decriminalize polygamy for the first time in 85 years.

"Lawmakers in the state House are considering legislation that would reclassify bigamy as an infraction in certain circumstances. The Republican-controlled Senate unanimously passed the bill earlier this week.

"More than 60% of Utah’s population belongs to the Church of Jesus Christ of Latter-day Saints, colloquially known as the Mormon Church, which practiced polygamy early in its history but banned it more than a century ago.

"Under current state law, bigamy is a felony, punishable by up to five years in prison. Bigamy is a legal term, defined as marrying someone while being legally married to another person.
...
"Utah Attorney General Sean Reyes has said his office only prosecutes bigamy crimes “against those who induce marriage under false pretenses or if there is a collateral malfeasance.”

"Sen. Henderson has said her bill would essentially codify the attorney general’s prevailing practices into law.
...
"Polygamy was outlawed in the U.S. in the 1880s. The practice was banned by the Mormon Church in 1890, as Utah sought statehood. Utah wouldn’t become a state until 1896, under the condition that it explicitly ban polygamy in its constitution.


"Since then, the state and the Mormon Church have taken a hard stance against polygamy, with the latter excommunicating its members for engaging in plural marriage.

"In 1935, the state criminalized bigamy. Those moves pushed polygamists to the fringes of society and in geographic isolation.

"The law has been challenged over the years. In 2013, U.S. District Judge Clark Waddoups declared unconstitutional a key portion of Utah’s polygamy law after it was challenged by stars of the reality-television show “Sister Wives.” An appeals court later dismissed that decision and the Supreme Court decided not to hear the appeal.

"According to a Gallup poll, acceptance of polygamy appears to be increasing in the U.S. In 2018, 18% of Americans believed marrying more than one person was morally acceptable. In 2003, 7% of those asked took the same stance."
*********

In common usage, I think "bigamy" refers to one person having two spouses (often a man with two wives), but it sounds as if, used as a legal term in Utah, bigamy includes what used to be called polygamy,  the situation of having more than one spouse at the same time. The usual form of polygamy is polygyny, when a man has more that one wife. A less usual form of polygamy is polyandry, when a woman has more than one husband.

All these terms arose when marriage, even multiple marriage, was thought of as between men and women.  We may need new terms for plural marriage now that we recognize same sex marriages.  For example, in a plural marriage of the future, will all the members be married to each other?

This would make legalizing plural marriage potentially more difficult, in terms of defining the legal status of all the spouses, than was legalizing same sex marriage.  In the case of same sex marriage, all the customary rights and obligations of traditional marriage in each state could be extended to same sex couples by a judicial order.  But, e.g. how does divorce work in a plural marriage--is it pairwise, or is it more like dissolving a partnership, or resigning from a partnership?  Can some parts of the marriage persist while other parts are dissolved?

This suggests to me that it may be some time before we see new, plural forms of marriage enshrined in law.  But I wouldn't bet the farm against it in the long term.

(In the meantime, I think we can say that if you support plural marriage, that's big o' you.)
**********

*In a geographically related story, the Salt Lake Tribune reported last week
BYU students celebrate as school removes ‘Homosexual Behavior’ section from its online Honor Code

Wednesday, February 26, 2020

Crime and punishment in the sex trade--an ongoing controversy in the U.S.

Two stories in the NY Times speak of the difficulty of regulating the sex trade, which may consist of both voluntary sex workers and victims of trafficking.

Here's a story from October:

In Washington, a Fight to Decriminalize Prostitution Divides Allies

Supporters say a bill being considered by the District of Columbia Council would protect prostitutes in the nation’s capital. Critics say it would be a boon to sex traffickers.  By Timothy Williams, Oct. 17, 2019

"The proposal is dividing the city’s progressive community, pitting some women’s groups against advocates for sex workers. Some prostitutes who have been sex trafficked find themselves on the other side from sex workers who have not been. But all sides agree that prostitution practiced openly would reverberate well beyond the city’s thriving but shadowy sex industry of street prostitution, massage parlors, strip clubs and high-end call girls."

*********
And a more recent story:
Charged With Prostitution, She Went to a Special Court. Did It Help?   By Christina Goldbaum, Jan. 6, 2020

"When New York State created a network of 12 Human Trafficking Intervention Courts, criminal justice professionals hailed it as an innovation. The courts send people into counseling sessions to help them leave the multibillion-dollar sex trade while dismissing their charges and sealing their records.
"But even as courts like these have begun to proliferate nationwide, New York’s own have come under increasing criticism, six years into their operation, that they are not living up to their promise.
...
"The division has become more pronounced in recent years with more mainstream acceptance of decriminalizing prostitution. The two camps have sparred over whether the goal should be to eliminate all sex trade — and by extension, sex trafficking — or make prostitution a regulated industry.

"While the debate unfolds, there is little question that the efforts have changed how prostitution is policed. The number of prostitution-related arrests in New York in 2019 dropped dramatically from the previous year."

Tuesday, February 25, 2020

Pay transparency in the NY Times

An article on the virtues of pay transparency in the NY Times publishes the salaries of all Times editors, reporters and columnists... just kidding.  But it does report on recent research about the effects of pay transparency:

Breaking the Salary Sharing Taboo
Transparency about salaries can make workplaces more equitable, especially for women and people of color. Why are so few Americans willing to open up?
By Susan Dominus

The article mentions several academic studies

Here's one from a forthcoming paper

"About a decade ago, a naturally occurring social experiment took place in Norway that revealed how people react when they are given the opportunity to learn not just a co-worker’s income but the salary of every citizen in the country. Key information from tax returns in Norway has been public since the 19th century, available to anyone willing to wait in line at City Hall and scour tax records. But that understandable interest in other people’s finances became something of a national obsession in 2001, when newspapers first started making the information searchable online. By 2009, one newspaper offered an app — instantly one of the country’s most downloaded — that allowed Facebook users to see leader boards that ranked friends’ salaries from highest to lowest. The app also created maps that allowed users to see the pay of all their neighbors. In 2010, during the first week that the most recent year’s information became available, Norwegians were Googling “skattelister” — tax lists — more than “YouTube,” according to data analyzed by Ricardo Perez-Truglia, now an assistant professor of economics at the U.C.L.A. Anderson School of Management; during that same period, Norwegians were scanning other people’s income more often than they were checking the weather. There were anecdotal reports of students’ being bullied for their families’ poverty, and increasingly, officials became uncomfortable with what the head of the Norwegian Tax Administration called the “peeping Tom” phenomenon (the media called it “tax porn”). In 2014, the law changed so that individuals could still access this public information — but the person whose information they were seeking would know who sought it. Salary searches plummeted, suggesting that Norwegian taboos around discussing pay are not, in the end, all that different from those in America.

Perez-Truglia realized he could use the case of the skattelister to determine the effect of that short window of widespread transparency on well-being, using data from a happiness survey that has been conducted in Norway since 1985. Perez-Truglia found that the newfound accessibility of other people’s pay led to a significant increase in the happiness gap: Higher-income earners were happier than they were before the information was widely available, and lower-income workers were less happy. (There was no change in happiness levels in the survey respondents with more limited access to the internet, further evidence that it was the availability of the skattelister that was having an influence on the survey results.)"

and here's the paper:
[Perez-Truglia, R. (2019). The Effects of Income Transparency on Well-Being: Evidence from a Natural Experiment. American Economic Review, forthcoming. Ungated] [ Slides]]
***********

Here's a link and an earlier post about another of the papers mentioned in the article,
Cullen, Zoë B., and Bobak Pakzad-Hurson. "Equilibrium Effects of Pay Transparency in a Simple Labor Market." Working Paper, April 2019. (Formerly two papers, "Equal Work for Unequal Pay" and "Is Pay Transparency Good?" Selected as Exemplary Applied Modeling Paper at EC '19.)

Friday, August 24, 2018

Monday, February 24, 2020

Good things to do after a kidney transplant: save an NHL game as an Emergency Backup Goalie (EBUG)

It turns out that in the NHL there is an Emergency Backup Goalie (EBUG) who is available to either team should the need arise. In this case, the Toronto EBUG saved the game for the visiting (opposing) team.

Emergency goalie completes journey from kidney transplant to NHL game
"Fifteen years ago, the aspiring NHL goalie had a kidney transplant with his mom Mary as his donor. His career was secondary. He was just glad to be alive.

"I never thought I'd play hockey again at that moment," Ayres said Saturday. "To go from that to what happened tonight is just unbelievable, unreal."

"Not only did Ayres play hockey Saturday, he was the winning goalie for the Carolina Hurricanes in a 6-3 victory against the Toronto Maple Leafs at Scotiabank Arena."
*************

42-year-old pulled out of crowd to make NHL debut ... and wins game
"David Ayres was sitting in the stands with his wife at Scotiabank Arena when Carolina Hurricanes goalie James Reimer went down with an injury. Ayers, the on-call emergency netminder in Toronto, left his seat and got half dressed into his gear on the off-chance something might happen to Carolina’s second option, Petr Mrazek.
...
"The next thing the 42-year-old Zamboni driver knew, he was walking down the tunnel and into the spotlight. And not long after, he had an improbable first NHL win. He is the oldest goalie in NHL history to win his regular-season debut.
...
"Ayres has been the emergency goalie in Toronto for about half the games this season and is available to either team. “You kind of think, ‘Oh well how’s this gonna end up?’” said Hurricanes head coach Rod Brind’Amour said. “That’s incredible. That’s why you do this.”

"Ayres was asked what he’ll remember most from the game. “These guys,” he said. “How great they were to me. The crowd in Toronto was unreal. Even though I was on the other team they were so receptive. Every time I made a save I could hear them cheering for me."


HT: Alex Chan

Markets and Coordination by Preston McAfee and Simon Wilkie

A high level overview of market design:

Teaching Old Markets New Tricks (gated, in Project Syndicate, Jan 23, 2020)

(ungated version:  Markets and Coordination)
by Preston McAfee  and Simon Wilkie

"Left: Markets are not delivering the results people need. Let the government run it.
Right: Markets created the giant increase in living standards we enjoy. Leave the market alone.

"Both positions are right – and wrong. Yes, market forces created the vast wealth of the western nations, and China shows what market forces can accomplish in two generations. At the same time, the way markets operate doesn’t necessarily produce the greatest good for the greatest number, and in some cases, such as pollution, laissez faire markets produce terrible outcomes.

"Market Design is a way of having your cake and eating it, too. Market design involves harnessing and directing market forces to produce socially desirable outcomes. It responds to Left by accepting that an unregulated market may produce undesirable outcomes, and adjusts the rules of competition to improve the outcome. It responds to Right by embracing market forces. "

Sunday, February 23, 2020

Exchanges for single earrings, odd shoes

Here's a NY Times story about what to do if you've lost one of a pair of earrings (and don't want to become a pirate...)

The Five Stages of Earring Loss--What to do when one earlobe goes bare. By Nancy Wartik

"In 2012, Ms. Kennedy created a Facebook page called My Lost Earring, inspired by the loss of one of her glass seagull earrings. They were a gift from her husband, but one of them vanished on a long-ago bike ride, a loss she still mourns.
...
"I put a photo on the My Lost Earring page, which Ms. Kennedy estimates has made at least 200 pairings. Matches can take weeks, months, sometimes years, she cautioned, encouraging me not to abandon hope."
***********

That reminded me of the National Odd Shoe Exchange

"NATIONAL ODD SHOE EXCHANGE was founded in St. Louis, Missouri in 1943. The late Ruth Rubin-Feldman created the organization as a support for polio survivors. Herself a survivor of polio, Ms. Feldman had feet of significantly different sizes. When wartime rationing made buying two sizes even more difficult, she conceived the idea of a service whereby people with similar problems could register their names and sizes. The registry served as a clearing-house that put people with similar interests and tastes, but opposite foot sizes, in touch with one another. Together the new friends could buy footwear and share the cost. No shoes were wasted and they saved money!

"With many veterans coming home from the war as amputees, the service grew and broadened its scope. First Lady Elenor Roosevelt gave NATIONAL ODD SHOE EXCHANGE nationwide recognition for providing such a valuable service."

Bob Montgomery, a transplant surgeon with a (new) heart, in the WSJ

The WSJ has the story:
A Transplant Surgeon Is Operating Again—With a New Heart
Robert Montgomery has resumed performing surgery after receiving a heart transplant from a donor with hepatitis C. But his journey back hasn’t been without complications.

"Robert Montgomery was performing his first kidney transplant as the lead surgeon since his own heart transplant in September of 2018.
...
"His patient, Daniel Flori, had had a heart transplant about 12 years ago, and the two swapped stories about their experiences before the kidney operation. ... Dr. Montgomery asked about Mr. Flori’s son, who donated a kidney in January to a stranger to set off the fast-moving donor chain that ultimately brought his father a kidney.
...
"Dr. Montgomery wants to be a role model for transplant patients. Only about 20% of kidney-transplant patients return to work. The numbers for heart-transplant recipients may be even less, he says. Many are on disability when they get a transplant and are afraid to lose their Medicare coverage."

Saturday, February 22, 2020

College Admissions--the musical (casting call)

Here's the casting call, from Playbill. (College admissions is interesting, and so is the labor market for theatrical performances...)

College Admissions Scandal Musical Ranked Now Accepting Submissions
BY DAN MEYER  FEB 21, 2020
 The casting call seeks performers ages 18–early 20s.

"The new musical Ranked, which follows the 2019 college admissions scandal, is now accepting video submissions for an upcoming industry presentation to be filmed by HBO for a documentary.

"The casting call seeks Non-Equity/Non-SAG-AFTRA performers ages 18–early 20s (to play 14–18 years old). To submit, send a video singing 32 bars of a contemporary pop or rock song (i.e. Pasek & Paul, Tom Kitt, Sara Bareilles), headshot and résumé to RankedCasting@gmail.com before February 26 at noon ET.

"Stephanie Klapper Casting will screen the audition tapes prior to an in-person casting call on March 2. Performers must be available for the entire rehearsal and presentation time period, March 16–20. A March 20 industry presentation at The Daryl Roth Theatre will be filmed by HBO."

Reading for marketplace designers from Andreessen Horowitz

Scott Kominers forwards this interesting reading list (which includes a nice summary of market design by him and Tom Eisenmann):

Reading for Marketplace Entrepreneurs

It appears on the Andreessen Horowitz website https://a16z.com/marketplace-100/ , which is well worth a look for those interested in starting a marketplace company, or maintaining one.

Friday, February 21, 2020

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."

Thursday, February 20, 2020

Coffee is good for you, and how it became a worldwide market--Ashok Rai at Williams College

First the good news from coffee science, via the NY Times

Is Coffee Good for You?
Yes! But it depends on the kind of coffee and the quantity.

"In moderation, coffee seems to be good for most people — that’s 3 to 5 cups, or up to 400 milligrams of caffeine.

“The evidence is pretty consistent that coffee is associated with a lower risk of mortality,” said Erikka Loftfield, a research fellow at the National Cancer Institute who has studied the beverage."
**********

And for those of you interested in the coffee market, here's a lecture by Ashok Rai that I would go to if I were near Williams College today:

Ashok Rai to Lecture on the Globalization of Coffee

"Ashok Rai, associate professor of economics at Williams College, will present a lecture titled “From Muslim to Christian: How Coffee Went Global.” The second of six talks in the college’s Faculty Lecture Series this semester, the lecture will take place on Thursday, Feb. 20, from 4:15 p.m. to 5:30 p.m. in Wege Auditorium. A reception will follow in Schow Atrium. The event is free and open to the public.

"Rai’s current research examines the globalization of coffee, drawing on history, literature, ecology, and on fieldwork in Central America and East Africa. "

Wednesday, February 19, 2020

Visa allocation, by Pathak, Rees-Jones and Sönmez

Here's a look at current U.S. visa allocation policies from a market design perspective.

Immigration  Lottery  Design:  Engineered  and  Coincidental  Consequences  of  H-1B  Reforms

Parag A. PathakAlex Rees-JonesTayfun Sönmez

NBER Working Paper No. 26767
Issued in February 2020
NBER Program(s):Labor Studies Program
Abstract: In response to increasing demand for high-skilled labor, the U.S. Congress legislated in 2005 that the H-1B visa program create 20,000 additional slots for advanced degree applicants on top of 65,000 slots open to all. Since then, the U.S. Customs and Immigration Service (USCIS) has implemented this policy through visa allocation rules that comply with this legislation. Following a directive in the April 2017 Buy American and Hire American Executive Order by President Trump, USCIS tweaked its H-1B visa allocation rule in 2019, in an explicit effort to increase the share of higher-skill beneficiaries, bypassing the need for Congressional approval to increase the number of advanced degree slots. The USCIS estimated that the rule change, engineered solely for this objective, would increase the number of higher-skill beneficiaries by more than 5,000 at the expense of lower-skill beneficiaries. In this paper, we characterize all visa allocation rules that comply with the legislation. Despite specifying rigid caps, we show that the legislation still allows for rules that can change the number of high-skill awards by as many as 14,000 in an average year. Of all rules that comply with the legislation, the 2019 rule adopted by the Trump administration produces the best possible outcome for higher-skill applicants and the worst possible outcome for lower skill applicants. We also discover that each of the two previous and much less known changes to the H-1B visa allocation rule resulted in more substantial changes to the share of higher-skill beneficiaries than the 2019 reform. The distributional effects of these earlier reforms in 2006 and 2008, however, were motivated by logistical considerations, potentially without understanding of their importance for the rate of higher-skill awards.

Tuesday, February 18, 2020

Market design and algorithmic criminal justice--by Jung, Kannan, Lee, Pai, Roth and Vohra

When fairness isn't your only goal, your other goals may help you choose among competing definitions of fairness.

Fair Prediction with Endogenous Behavior
Christopher Jung, Sampath Kannan, Changhwa Lee, Mallesh M. Pai, Aaron Roth,and Rakesh Vohra
February 17, 2020

Abstract: There  is  increasing  regulatory  interest  in  whether  machine  learning  algorithms  deployed  in  consequential domains (e.g.  in criminal justice) treat different demographic groups “fairly.”  However, there are several proposed notions of fairness, typically mutually incompatible.  Using criminal justice as an example,  we study a model in which society chooses an incarceration rule.  Agents of different demographic groups differ in their outside options (e.g.  opportunity for legal employment) and decide whether to commit crimes.  We show that equalizing type I and type II errors across groups is consistent with the goal of minimizing the overall crime rate; other popular notions of fairness are not.
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And here's a blog post about the paper by one of the authors:

Fair Prediction with Endogenous Behavior
Can Game Theory Help Us Choose Among Fairness Constraints?

"...The crime-minimizing solution is the one that sets different thresholds on posterior probabilities (i.e. uniform thresholds on signals) so as to equalize false positive rates and false negative rates. In other words, to minimize crime, society should explicitly commit to not conditioning on group membership, even when group membership is statistically informative for the goal of predicting crime.

"Why? Its because although using demographic information is statistically informative for the goal of predicting crime when base rates differ, it is not something that is under the control of individuals --- they can control their own choices, but not what group they were born into. And making decisions about individuals using information that is not under their control has the effect of distorting their dis-incentive to commit crime --- it ends up providing less of a dis-incentive to individuals from the higher crime group (since they are more likely to be wrongly incarcerated even if they don't commit a crime). And because in our model people are rational actors, minimizing crime is all about managing incentives. "