Tuesday, August 11, 2020

Transplanting two kidneys from older deceased donors to reduce discards

Here's a venerable but newly fashionable idea in transplantation, particularly for deceased donors whose (individual) kidneys have already been rejected when offered.  Transplant both kidneys into the same recipient, to reduce the risk.

Here's a paper from January:
Lee, K.W., Park, J.B., Cha, S.R. et al. Dual kidney transplantation offers a safe and effective way to use kidneys from deceased donors older than 70 years. BMC Nephrol 21, 3 (2020). https://doi.org/10.1186/s12882-019-1664-8

And here's a very recent news article talking about a different, larger study:

By Melissa J. Webb

"Using data from the United Kingdom Transplant Registry, they identified 7,841 kidneys procured from deceased donors aged 60 years or older, finding that 17% of these were discarded.

Considering the remaining kidneys used for transplant (356 for dual; 5,032 for single), the researchers determined that both donors and recipients of dual transplants were older (median, 73 years vs. 66 years and 64 years vs. 61 years, respectively). Donors of kidneys used in dual transplantation also had higher United States Kidney Donor Risk Indices (2.48 vs 1.98 for those used in single transplants).

After adjusting for confounders, the researchers observed similar 5-year graft survival between dual and single transplants (HR = 0.81), as well as a higher median eGFR at 12 months for recipients of dual transplants (40 mL/min/1.73m2 vs. 36 mL/min/1.73m2)."

Monday, August 10, 2020

Reputation among thieves: ransomware and kidnapping

Like everyone else, I occasionally get notifications of data breaches from organizations with which I have digital relations.  Often the breach involved a third party.  Sometimes the breach involves the theft of data accompanied by a demand of ransom--i.e. the victim is invited to pay the cybercriminal, who then promises to destroy the data instead of selling it on the dark web or otherwise using it.

This bears some resemblance to the kidnapping business, and its high-seas version, piracy.

Here's part of an email I recently received informing me of such a breach, and subsequent payment of ransom.

"I’m writing to inform you that Blackbaud, the company that hosts [xxx’s] relationship management system, suffered a security incident in May. Blackbaud is the world’s largest provider of fundraising technology for non-profits and educational institutions, and many organizations have been impacted by this incident.
"We were also informed by Blackbaud that in order to protect data and mitigate potential identity theft, it met the cybercriminal’s ransomware demand. Blackbaud has advised us that it received assurances from the cybercriminal and third-party experts that the data was destroyed. Blackbaud has been monitoring the web in an effort to verify the data accessed by the cybercriminal has not been misused. "
Why should "assurances from the cybercriminal" be reassuring? (and for how long?).  And what are the roles played by "third-party experts"?

My guess is that, as in the kidnapping biz, intermediaries have emerged to conduct the negotiations, get some sort of assurances, and make it possible for criminal organizations to maintain reputations for honor among thieves.

It is of course possible to regard ransom paying as a repugnant transaction that facilitates ransomware, kidnapping, etc.  In fact the U.S. for some time made it a crime to pay ransom to kidnappers, but relaxed that view over time, as kidnapping became a bigger international business, and there was often a considerable desire (sometimes covered by insurance) to pay ransom when it seemed the best way to recover the kidnapped person alive.

Here are some related posts which touch on that story:

Monday, June 24, 2019  Kidnapping insurance

Tuesday, September 13, 2016 Ransom as a (not so) repugnant transaction

Monday, August 9, 2010 Brokers for pirate ransom

Saturday, December 5, 2009 Market for kidnapping

Sunday, November 30, 2008 Pirate ransom: counterparty risk

Sunday, August 9, 2020

Experimental Economics SITE conference at Stanford, by Zoom, Aug 10 and 11, 2020

 Tomorrow and Tuesday, here's the SITE Experimental Economics conference schedule (Mon Aug. 10 and Tuesday Aug. 11).  

Muriel Introduce SITE confernece
SESSION 1: 9am - 10:30am pacific (12pm eastern, 6pm europe)Lise - in charge
1Overriding in Teams: The Role of Beliefs, Social Image, and GenderMaria Recalde, University of Melbourne(Lise Q)
2Information and the Persistence of the Gender Wage Gap: Early Evidence from California's Salary History BanBenjamin Hansen, University of Oregon(Lise Q)
3Attention as Human CapitalHeather Schofield, University of Pennsylvania(Colin Q)
10:30am - 11am pacific: Break/Discussion (1pm eastern, 7pm europe)
SESSION 2: 11 -12:30pm pacific (2pm eastern, 8pm europe)Muriel - in charge
4Social Learning in Groups: an Experimental StudyMarina Agranov, Caltech(Muriel Q)
5Beliefs in Repeated GamesGuillaume Frechette, NYU(Muriel Q)
6Beyond Ordinal: The Value of Indifferences and Cardinal Information in MatchingClayton Featherstone, University of Pennsylvania(Muriel Q)
12:30pm - 1pm pacific: Break/Discussion (3:30pm eastern, 9:30pm europe)
Day 2 (August 11)
SESSION 3: 9:30am -10:30pm pacific (12:30pm eastern, 6:30pm europe)Lise - in charge
7The Burden of Holding DebtAlejandro Martínez-Marquina, Stanford University
8Claiming Credit: Gender, Memory, and Social NormsJonas Mueller-Gastell, Stanford University
9It’s Not my Fault: Excuse-Seeking Behavior in the Intertemporal DomainMarissa Lepper, University of Pittsburgh
10Do Actions Speak Louder than Motives? Evaluating the Effectiveness of Image-FundraisingPun (pronounced like "Poon") Winichakul, University of Pittsburgh
10:30am - 11am pacific: Break/Discussion (1pm eastern, 7pm europe)
SESSION 4: 11 -12:30pm pacific (2pm eastern, 8pm europe)Muriel - in charge
11Fairness Across the World: Preferences and BeliefsAlexander W. Cappelen, Norwegian School of Economics(Christine Q)
12Cognitive Flexibility or Moral Commitment? Evidence of Anticipated Belief Distortion
Silvia Saccardo, Carnegie Mellon University(Christine Q)
13Digital AddictionHunt Allcott, New York University and Microsoft Research(Colin Q)
Muriel close SITE confernece
12:30pm - 1pm pacific: Break/Discussion (3:30pm eastern, 9:30pm europe)

Saturday, August 8, 2020

Is convalescent plasma useful for treating covid-19?

The reported results on convalescent plasma are so far still quite incomplete, and mixed.  If I had to summarize, I'd say that a growing body of evidence suggests that treating early stage (e.g. just hospitalized) covid-19 patients increases and speeds the chance of recovery, while there is little convincing evidence that convalescent plasma helps more severely ill patients who have begun to have serious complications.

Here is a recent WSJ article:

By Amy Dockser Marcus

"Hospitalized Covid-19 patients who received transfusions of blood plasma rich with antibodies from recovered patients reduced their mortality rate by about 50%, according to researchers running a large national study.
"The researchers said they saw signs that the treatment might be working in patients who received high levels of antibodies in plasma early in the course of their illness. They based their conclusions on an analysis of about 3,000 patients."

Here's a recent paper in JAMA on a very small randomized trial in China that doesn't find statistically significant effects on patients who 

August 4, 2020
Ling Li, MD, PhD; Wei Zhang, MD; Yu Hu, MD, PhD; Xunliang Tong, MD, PhD; Shangen Zheng, MD; Juntao Yang, PhD; Yujie Kong, MD; Lili Ren, PhD; Qing Wei, MD; Heng Mei, MD, PhD; Caiying Hu, MD; Cuihua Tao, MD; Ru Yang, MD; Jue Wang, MD; Yongpei Yu, PhD; Yong Guo, PhD; Xiaoxiong Wu, MD; Zhihua Xu, MD; Li Zeng, MD; Nian Xiong, MD, PhD; Lifeng Chen, MD; Juan Wang, MD; Ning Man, MD; Yu Liu, PhD; Haixia Xu, MD; E. Deng, MS; Xuejun Zhang, MS; Chenyue Li, MD; Conghui Wang, PhD; Shisheng Su, PhD; Linqi Zhang, PhD; Jianwei Wang, PhD; Yanyun Wu, MD, PhD; Zhong Liu, MD, PhD
  JAMA. 2020; 324(5):460-470. doi: 10.1001/jama.2020.10044

Abstract: This randomized trial compares the effects of convalescent plasma therapy with standard care vs standard care alone on time to clinical improvement among patients with severe or life-threatening COVID-19 disease in China.

"Among patients with severe or life-threatening COVID-19, convalescent plasma therapy added to standard treatment did not significantly improve the time to clinical improvement within 28 days, although the trial was terminated early and may have been underpowered to detect a clinically important difference."

My last donation had high enough antibodies to qualify me for another: I hope these are going to patients for whom they will be useful.

Friday, August 7, 2020

Global kidney exchange between Abu Dhabi and Kerala (India)

Here is an article in the newspaper Malayalam Manorama, in Malayalam, the language spoken in Kerala, about a global kidney exchange between hospitals in Abu Dhabi in the United Arab Emirates, and in Kerala in India.

The url hints at the story: the exchange was between a Kerala hospital and a UAE hospital that both used kidney exchange software provided by Mike Rees's organization, the Alliance for Paired Kidney Donation (APKD), to identify the exchange, which was performed in India:

The article says SEHA Kidney Care Staff( Anan Purushothaman, Sheenamma Varghese , Siddiq Anwar) with Dr Mike Rees from Alliance For Paired Donation helped find a compatible  kidney donor in India via the “Global Kidney Paired Exchange”. Dr Feroz Aziz then successfully transplanted the two pairs.

Kim Krawiec, through a friend fluent in Malayalam, gives the following summary:

"The article goes on to say that Najla was in want of a kidney donor. Even though she had 3 of her relatives who were ready to donate none of them were compatible. She was asked to get in touch with the organisation called Alliance for Paired Kidney Donation, where they find donors all around the world using the latest technology. With the help of this organisation and the latest technology, not to mention the doctors and nurses she was able to find a compatible donor. At the same time Najma's mother was able to donate her kidney to the Abu Dhabi donor's husband. Now all are well and back to normal life."

Thursday, August 6, 2020

Is randomization repugnant?

Patrick R. Heck,  Christopher F. Chabris,  Duncan J. Watts, and Michelle N. Meyer
PNAS first published July 27, 2020 https://doi.org/10.1073/pnas.2009030117
Edited by Margaret Levi, Stanford University, Stanford, CA, and approved July 4, 2020 (received for review May 13, 2020)
Abstract: We resolve a controversy over two competing hypotheses about why people object to randomized experiments: 1) People unsurprisingly object to experiments only when they object to a policy or treatment the experiment contains, or 2) people can paradoxically object to experiments even when they approve of implementing either condition for everyone. Using multiple measures of preference and test criteria in five preregistered within-subjects studies with 1,955 participants, we find that people often disapprove of experiments involving randomization despite approving of the policies or treatments to be tested.

Wednesday, August 5, 2020

Admissions to polytechnics in Finland, by Kristian Koerselman

Here's a paper that gives a very clear description of the centralized application process for Finnish polytechnics (applied universities), which gives applicants a complicated strategic problem, and results in many applicants re-applying in subsequent years.

Assignments are by a (school proposing) deferred acceptance algorithm, but applicants get extra points in a school's preferences by listing it first, they can only list four programs, and they must choose which exams to take.

Why Finnish polytechnics reject top applicants
Kristian Koerselman
Education Economics, July 2020

"The Finnish polytechnic assignment provides us with an example where applicants are asked to strategize in their applications while having poor prior information on the set of programs that would admit them. These features should in and of themselves already be expected to cause a poor assignment outcome. I highlight the additional role which entrance exams appear to play in creating what should arguably be seen as a misrepresentation of true admission criteria analogous to a misrepresentation of applicants' true preferences. Because applicants take and retake different entrance exams in different years, programs rank the same applicants differently in different years, giving applicants an incentive to reapply even if they were originally assigned to their within-year most preferred feasible program.
"Finland provides 9 years of compulsory, comprehensive education, after which almost all students continue in approximately equal proportions to either an academically-oriented high school or to a vocational school. High school concludes with a set of nationally standardized and externally graded matriculation exams. Though students have a reasonable amount of freedom in choosing the subjects they want to take an exam in, they have to take into account that different higher education programs value matriculation exam grades in different subjects differently.

Higher education is provided by polytechnics, also called universities of applied sciences, and by universities. The former mainly offer bachelor programs, and the latter mainly combined bachelor/master programs. About half of each birth cohort ever enrolls in higher education, with total yearly admissions somewhat larger at polytechnics than at universities. Although it is not uncommon for vocational school graduates to apply to a polytechnic, high school graduates are the largest group of polytechnic applicants.
"Higher education applications are extremely competitive, with for example only about one-third of polytechnic applicants being admitted nationally each year. Rejected applicants are likely to reapply, often multiple years, and even admitted applicants often reapply. Re-applications are an important reason why the numbers of applicants per seat are so large. Applicants effectively queue into higher education, likely causing them to be admitted at an unnecessarily old age, and therefore also to graduate at an unnecessarily old age. The 2011 polytechnic applicants on which this study is based for example had on average graduated from high school already two and a half years earlier, and many of them would be older still when they were finally admitted to the higher education program they would eventually graduate from.

"All higher education applications are made to a national clearinghouse. Polytechnic admission decisions are generally made centrally by the clearinghouse itself, while university admission decisions are generally not. In this paper, I analyze the 2011 centralized assignment of high school graduates to Finnish polytechnics. In total, 50,894 high school graduates applied to 16,655 seats in 440 programs, divided over 8 fields.

"The application process starts in March, when applicants can apply to up to four programs in order of preference. Applicants must then choose which entrance exams to prepare for and take, typically in May or June. After the entrance exams have been graded, an admission score is calculated for each application. This score is mainly based on applicants' matriculation exam grade point averages and entrance exam results. The weights assigned to different matriculation exam subjects are typically shared within each field, and entrance exams tend to be shared as well. Extra points are awarded for the first listed choice, as well as for factors like relevant labor market experience. The relative weight of the different admission score components in determining the admission score can be seen in Table 2.

"Based on their submitted preference ordering and on their admission scores, applicants are assigned to programs through a centrally run program-proposing deferred acceptance algorithm, each applicant either being admitted to a single program or not being assigned at all. Admitted applicants then either accept their seat or reject it. A much smaller second round of offers is sent out by the programs themselves to make up for first-round rejections. The second round of the process ends at the start of the fall term in September.
"Applicants have multiple reasons to strategize in choosing which programs to apply to. Among others, the fact that applicants receive extra points for their first listed choice implies that they will want to list a program first where they have a chance to actually be admitted. Similarly, the four-program limitation means not only that there may be programs acceptable to the applicant which the applicant is not allowed to list, but also that the applicant will need to use the four allowed applications wisely. Third, the applicant faces a strategic choice in which entrance exams to prepare for and take, typically concentrating all effort on a single application. Fourth, the use of a program-proposing algorithm may in and of itself already give applicants an incentive to strategize."
"Though applicants receive good indications of their matriculation exam grades before they apply, and may be aware of previous years' admission score cut-offs, they however necessarily learn their entrance exam scores only after choosing where to apply and which entrance exams to take, adding a considerable degree of uncertainty to their application.
"When classifying applicants into thirds based on their program-specific matriculation exam GPA, as many as 54% of top third applicants remain unassigned anywhere. Even using the actual admission score, 34% of top third applicants remain unassigned.
"Even if applicants do apply to more than one program, their admission chances are relatively low for programs listed second, third and fourth, with the probability of being assigned to a program being 27% for the program listed first, but only between 3 and 4 per cent for programs listed lower. This is partly due to the extra points given for the first listed program, but is probably also related to applicants' strategic choices on which entrance exams to take. "

Tuesday, August 4, 2020

Unbalanced matching markets with short preference lists may not have very unequal stable matchings, by Kanoria, Min, and Qian

Here's a new paper exploring what happens when unbalanced matching markets (with unequal numbers of participants on opposite sides) also have short preference lists, so that each individual has preferences over only a potentially small fraction of possible mates.

Which Random Matching Markets Exhibit a Stark Effect of Competition?
Yash Kanoria, Seungki Min, Pengyu Qian

"We revisit the popular random matching market model introduced by Knuth (1976) and Pittel (1989), and shown by Ashlagi, Kanoria and Leshno (2013) to exhibit a "stark effect of competition", i.e., with any difference in the number of agents on the two sides, the short side agents obtain substantially better outcomes. We generalize the model to allow "partially connected" markets with each agent having an average degree d in a random (undirected) graph. Each agent has a (uniformly random) preference ranking over only their neighbors in the graph. We characterize stable matchings in large markets and find that the short side enjoys a significant advantage only for d exceeding (log^2 n where n is the number of agents on one side: For moderately connected markets with  d=o(log^2 n), we find that there is no stark effect of competition, with agents on both sides getting a sqrt(d)  ranked partner on average. Notably, this regime extends far beyond the connectivity threshold of d=Θ(logn). In contrast, for densely connected markets with d=ω(log2n), we find that the short side agents get logn-ranked partner on average, while the long side agents get a partner of (much larger) rank d/logn on average. Numerical simulations of our model confirm and sharpen our theoretical predictions. Since preference list lengths in most real-world matching markets are much below (log^2 n), our findings may help explain why available datasets do not exhibit a strong effect of competition."

Monday, August 3, 2020

Josh Morrison and health policy activism: kidneys and covid

Here's a profile of Josh Morrison, one of the most interesting health care policy activists I've encountered.  I first met him when he was the general counsel of the kidney exchange organization The Alliance for Paired Kidney Donation, and since then he's created new organizations (with evocative names) and new policies.

"Morrison donated a kidney in 2011, months into his job as a corporate attorney. A few years later he abandoned the law for a more mission-driven career helping people find kidney donors, eventually starting the nonprofit Waitlist Zero in 2014.

"In his telling, his parents “really hated” the idea of being a live organ donor. What he’s planning next terrifies them: Morrison wants to give himself Covid-19 for the sake of science.
"The 35-year-old from Brooklyn is the leader of 1Day Sooner, a grassroots organization he co-founded in the spring with a radical idea: Speed up vaccine testing by giving the coronavirus to willing recruits. Including Morrison and his co-founder, 22-year-old Stanford human biology graduate Sophie Rose, more than 30,000 people from 140 countries are signed up — a pool of applicants offering to enlist in what’s known as a human challenge trial.
"Human challenge trials involve deliberately infecting small groups of vaccinated volunteers. In a time of social distancing, mask-wearing, and the public’s general leeriness of contracting Covid-19, some researchers, doctors, and ethicists say challenge trials are worthwhile. Unlike traditional Phase 3 clinical trials, which sign up thousands of participants, inject some with a vaccine and others with a placebo, and then wait for people to encounter the virus in everyday life, there’s no waiting on people to catch a virus in a challenge trial. This means it can be completed in weeks instead of months or years, potentially yielding data on vaccine efficacy much more quickly.

"On July 15, human challenge trials for the coronavirus received their biggest endorsement. Adrian Hill, director of the Jenner Institute at the University of Oxford in the U.K., announced that Oxford scientists — already hard at work on a promising coronavirus vaccine — want to launch a challenge trial."

Sunday, August 2, 2020

Foie gras sale ban in CA doesn't rule out interstate commerce

The Mercury News has the lastest twist on the long running saga of foie gras in California:

Foie gras ruling puts it back on Californians’ plates, but not on restaurant menus
Delicacy can be sold, shipped by out-of-state producers; reselling it remains verboten

"Foie gras can again be legally shipped to Californians for consumption at home, according to a new ruling. But diners won’t find the fatty goose and duck livers back on restaurant menus.

"U.S. District Judge Stephen V. Wilson ruled Tuesday in Los Angeles that the sale of foie gras doesn’t violate the law if the seller is located outside of California and the product is brought into the state by a third-party delivery service, the Associated Press reported, adding that the California attorney general’s office is reviewing the decision.

"However, foie gras still can’t legally be resold — which means restaurant sales are prohibited, according to attorneys for both the plaintiffs and defendants.
"The issue of whether foie gras can be produced and/or sold in California had been simmering in courts for years.

California’s ban on the production and sale of foie gras (pronounced fwah grah) originally went into effect July 1, 2012, eight years after SB 1520 (by then-Sen. John Burton) was signed into law by then-Gov. Arnold Schwarzenegger, in 2004."

See all my posts on foie gras.

Saturday, August 1, 2020

Arranged marriage, in India, on television

The Guardian and the Indian Express have the story about a tv show about arranged marriage, a venerable institution that is becoming controversial.

Here's the Guardian:

Indian Matchmaking: Netflix's 'divisive' dating show causes storm
Series following contestants hoping to be chosen for arranged marriage has divided opinion in India
by Hannah Ellis-Petersen

"For some, Indian Matchmaking represents an unacceptable normalising of the regressive standards forced on Indian women to in order to be seen as a “suitable” wife, while pushing the unspoken issue of caste under the carpet.
"The eight-part series follows Taparia as she attempts to find appropriate matches for clients both in India and across the world in order to set up arranged marriages, often on behalf of their client’s parents. It is a show set in a world of upper-class affluence, where Indian families can afford to hire Taparia’s expensive services and even fly her across the world to find them, or their children, a suitable match.

"Arranged marriage remains prevalent in India. As Taparia says in the show, arranged marriage is just described as “marriage” while it is “love marriage” that is spoken of as outside the norm. Newspapers are still full of matrimonial adverts where women are reduced to three-line descriptions of their “fair skinned”, “accomplished” or “modern yet traditional” attributes.

"Indian Matchmaking’s uncritical presentation of its clients’ “criteria” – usually fair-skinned women from a “good” family - has come in for particular criticism.

"Critics have said the show perpetuates damaging ideas around colourism and caste – the Hindu system of hierarchy, which rigidly designates someone’s class and social status. Dalits, India’s lowest class, still undergo rampant discrimination and abuse in society while the upper Brahmin caste hold much of the power and influence. Cross-caste marriage in India can get you killed.

“Indian Matchmaking is really a cesspool of casteism, colourism, sexism, classism,” wrote one Twitter user."

And here's the Indian Express:

Indian Matchmaking: An 8-episode of misguided gender politics, ultimately a betrayal for Indian audiences
By cherry picking its clients and assorting stories it wants to tell, by ticking boxes of caste, religion and class as imperative for an arranged alliance, Indian Matchmaking panders to the West gaze with complying obedience.
by Ishita Sengupta

"Positioned as an outlet to familiarise the world with a practice peculiar to India and Indians; the documentary could have been a first-hand exploration about the evolving origin of a cultural custom and the multifarious ways people go about it. And for millennials back home, it could affirm our rejection of a practice we long recognise as outdated or be a vehicle to convince us of its efficiency in a language we comprehend better than our parents’ monologues. But Indian Matchmaking dilutes an age-old practice by blunting the pointed shards on which it has stood for years. The end result is an eight-episode betrayal for the audience in India and a cut-to-fit documentary about the country and its traditions for the West, confirming every suspicion they nurtured.

"Created by Smriti Mundhra, who previously co-directed A Suitable Girl in 2017, it follows Sima Taparia, one of India’s top matchmakers as she visits her clientele spread across India and abroad. At the very outset, Taparia (“from Mumbai”) insists, “Matches are made in heaven and God has given me the job of making them successful on earth,” thereby placing herself beyond reproach. But in her job of a self-declared messiah (it is never shown how much she earns) intending to bring together people with the supposed divine connection, she falls back on caste, class, complexion, height and sometimes breadth of smiles as plausible criteria for two people to give each other a shot at spending their lives together."

And Livemint:

Opinion | What economic studies say about our marriage market
 29 Jul 2020,  by Anirudh Tagat
"A matchmaking show on Netflix seems to skim over the market deficiencies that scholars have studied in depth"
Update:  and this, from the NY Times, Aug 5--

By Sanjena Sathian

"It’s easy to applaud stories about rejecting old customs in favor of modern ideals. It’s harder, yet worthwhile, to sit with the subtler tension between tradition and modernity. This is what the great marriage plots have always considered: a mannered society, and how to live within it."

Friday, July 31, 2020

Australia-New Zealand kidney exchange program

New Zealand and Australia are cooperating with cross-border, international kidney exchange.

The Australian has the story:
The chain gang

"Facilitated by the Organ and Tissue Authority, the Australian and New Zealand Paired Kidney Exchange (ANZKX) has now given 42 people new kidneys since that first operation late last year. While paired kidney exchange has happened in Australia since 2010, this is the first true international collaboration. Eleven chains of operations occurred before Covid-19 stalled things in March, but recruitment into the program continues and there are six surgeries planned in Australia for August.
"[Linda] Cantwell is the ­Australian Red Cross ANZKX tissue typing scientist. She’s gatekeeper to the matrix of matches needed to link up potential pairs. There are currently 150 donors and 128 potential recipients in the pool, but for some people only one donor in 10,000 might be suitable. A computer program called OrganMatch runs the algorithms based on each person’s unique antibody profile and tissue typing, and potential matches from up to 300,000 different chains are produced."

And here's a related story from Australia's Daily Telegraph:

Organ donation hit hard by COVID-19 global pandemic
by Jane Hansen

"The Australian and New Zealand Paired Kidney Exchange was suspended from March 6 and can only begin if and when travel restrictions lift.

"Deceased kidney and live kidney donor programs across Australia were also suspended from March 24 and only recommenced in May, blowing out waitlists.

"Liver, heart, lung, paediatric and multi-organ transplant programs have continued but are subject to case-by-case review by the National Transplantation and Donation Rapid Response Taskforce, which meets weekly to discuss the response to COVID-19, the Organ and Tissue Authority said.

"According to the latest figures for 2019, the families of 548 loved ones transformed the lives of 1444 Australians by agreeing to organ donation.

"In 2019, 1309 had the potential to be organ donors but just over half of those families agreed."

Thursday, July 30, 2020

Surrogacy and global kidney exchange receive popular support even where banned, in PNAS by Roth and Wang

Popular repugnance contrasts with legal bans on controversial markets
Alvin E. Roth and  Stephanie W. Wang
PNAS first published July 29, 2020 https://doi.org/10.1073/pnas.2005828117
reviewed by Nicola Lacetera and Mario Macis

Abstract: We study popular attitudes in Germany, Spain, the Philippines, and the United States toward three controversial markets—prostitution, surrogacy, and global kidney exchange (GKE). Of those markets, only prostitution is banned in the United States and the Philippines, and only prostitution is allowed in Germany and Spain. Unlike prostitution, majorities support legalization of surrogacy and GKE in all four countries. So, there is not a simple relation between public support for markets, or bans, and their legal and regulatory status. Because both markets and bans on markets require social support to work well, this sheds light on the prospects for effective regulation of controversial markets.

"Our main result is that (unlike prostitution) the laws banning surrogacy and GKE do not seem to reflect popular demand. Neither do these bans reflect that opponents of legalization feel more strongly than supporters.
"All three transactions are the subject of current debate in at least one of the countries we surveyed.¶¶ Based on the results of our surveys, we do not see entrenched popular resistance to either surrogacy or GKE (or simple kidney exchange) where it is presently illegal, and thus, we anticipate that efforts to lift or circumvent current restrictions are likely to be increasingly successful, while efforts to legalize or decriminalize prostitution where it is presently illegal may face greater opposition from the general public.

"Understanding these issues is important, not just for the hundreds of Spanish couples stranded outside of Spain while they look for a way to bring their surrogate children home and not just for the people in need of kidney exchange but for whom it is out of reach in Germany or in the Philippines. These issues are also of importance to social scientists in general and economists in particular. When markets enjoy social support, when they are banned, and when, in turn, bans are socially supported are questions that touch upon many transactions, particularly as social and economic interactions are increasingly globalized.

"Our findings suggest that the answer to these questions may not be found in general public sentiment in countries that ban markets or legalize them. Rather, we may have to look to the functioning of particular interested groups, perhaps with professional or even religious interests, that are able to influence legislation in the absence of strong views (or even interest) among the general public about the markets in question."

Wednesday, July 29, 2020

Emmanuel Farhi 1978-2020

Emmanuel Farhi passed away last week, unexpectedly and tragically.  He was my colleague at Harvard, and we had recently sought to hire him at Stanford.  

Here's the Harvard Economics department memorial, which contains moving testimonials: 

This has been a hard year at Harvard, with four deaths in the department in the last 12 months.

Tuesday, July 28, 2020

Stanford campus in lockdown--pictures

Stanford is under-crowded in these coronavirus lockdown days of July...

Monday, July 27, 2020

JET Stanford

Here's an email sent yesterday by my department chair:

"It has belatedly come to my attention that the Journal of Economic Theory recently published a 50th anniversary issue, which included a collection of the 50 most influential papers included in the journal since its inception.  Nine of those papers included coauthors who are members of our department.  Special congratulations to Paul Milgrom, who coauthored four of them! 

Here are the Stanford-Econ-coauthored papers on the list (I REALLY hope I didn't overlook any -- if so, please let me know!): 

David Kreps, Paul Milgrom, John Roberts, and Robert Wilson, “Rational cooperation in the finitely repeated prisoners’ dilemma,” JET, August 1982. 
Paul Milgrom and John Roberts, “Predation, reputation, and entry deterrence,” JET, August 1982. 
Paul Milgrom and Nancy Stokey, “Information, trade and common knowledge,” JET, February 1982.   
B. Douglas Bernheim, Bezalel Peleg, and Michael Whinston, “Coalition-Proof Nash Equilibria I. Concepts,” JET, June 1987. 
Drew Fudenberg, Bengt Holmstrom, and Paul Milgrom, “Short-term contracts and long-term agency relationships,” JET, June 1990. 
Matthew Jackson and Asher Wolinsky, “A Strategic Model of Social and Economic Networks,” JET, October 1996. 
Matthew Jackson and Alison Watts, “The evolution of social and economic networks,” JET, October 2002. 
Larry Epstein and Martin Schneider, “Recursive multiple-priors,” JET, November 2003. 
Alvin Roth, Tayfun Sonmez, and M. Utku Unver, “Pairwise kidney exchange,” JET, December 2005. 



B. Douglas Bernheim
Edward Ames Edmonds Professor of Economics
Chair, Department of Economics"

And here is the full list of 50 papers:

Sunday, July 26, 2020

Chocolate is good for your heart

Breaking (good) news on the chocolate science front--from the European Journal of Preventive Cardiology

Association between chocolate consumption and risk of coronary artery disease: a systematic review and meta-analysis
Chayakrit Krittanawong, Bharat Narasimhan, Zhen Wang, Joshua Hahn, Hafeez Ul Hassan Virk, Ann M Farrell, HongJu Zhang, WH Wilson Tang
First Published July 22, 2020  https://doi.org/10.1177/2047487320936787

"Clinical trials have shown that the consumption of chocolate has favorable effects on blood pressure and endothelial function.1 The previous meta-analysis showed that many dietary components, including chocolate, appear to be beneficial for cardiovascular disease.2 However, the potential benefit of increased chocolate consumption, reducing coronary artery disease (CAD) risk is not known. We aimed to explore the association between chocolate consumption and CAD.
"In the present meta-analysis, we found that chocolate consumption (>1 time per week or >3.5 times per month) is associated with a reduced risk of CAD."

Saturday, July 25, 2020

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."

Friday, July 24, 2020

Experiments on school choice: a survey by Hakimov and Kübler

Hakimov, R., Kübler, D. Experiments on centralized school choice and college admissions: a survey. Exp Econ (2020). https://doi.org/10.1007/s10683-020-09667-7

Abstract: The paper surveys the experimental literature on centralized matching markets, covering school choice and college admissions models. In the school choice model, one side of the market (schools) is not strategic, and rules (priorities) guide the acceptance decisions. The model covers applications such as school choice programs, centralized university admissions in many countries, and the centralized assignment of teachers to schools. In the college admissions model, both sides of the market are strategic. It applies to college and university admissions in countries where universities can select students, and centralized labor markets such as the assignment of doctors to hospitals. The survey discusses, among other things, the comparison of various centralized mechanisms, the optimality of participants’ strategies, learning by applicants and their behavioral biases, as well as the role of communication, information, and advice. The main experimental findings considered in the survey concern truth-telling and strategic manipulations by the agents, as well as the stability and efficiency of the matching outcome.

From the Conclusions:

"The purpose and style of experiments on school choice and college admissions has changed over time. Many of the early experiments were tests of the theory. Horse races between different school choice mechanisms were conducted. Recently, many studies have dealt with systematic biases in behavior that matter in matching markets, such as bounded rationality, biased self-assessments, etc. Moreover, recent work also focuses on the question of how the exact implementation of a mechanism, e.g., static versus dynamic, with or without advice, afects market outcomes. Thus, the matching literature has started to establish behavioral regularities that can be of interest for policy makers involved in market design and behavioral theorists."

Thursday, July 23, 2020

Deceased organ donation by presumed consent, when families must also consent

Presumed consent to be an organ donor becomes complicated when the next of kin of the deceased potential donor must also consent:

Costa-Font, J., Rudisill, C. & Salcher-Konrad, M. ‘Relative Consent’ or ‘Presumed Consent’? Organ donation attitudes and behaviour. Eur J Health Econ (2020). https://doi.org/10.1007/s10198-020-01214-8

Abstract: "Legislation, in the form of presumed consent, has been argued to boost organ donation but most evidence disregards the practice of seeking relative’s consent, which can either ‘veto’ donation decisions, or ‘legitimize them’, by removing any possible conflict with the donor’s family. We study the effect of presumed consent alongside family consent on individuals’ willingness to donate (WTD) one’s own and relatives’ organs, and on actual organ donation behaviours. Using data from 28 European countries for the period 2002–2010, we found that presumed consent (PC) policies are associated with increased willingness to donate organs, but this effect was attenuated once internal family discussions on organ donation were controlled for. Our findings indicate that relative’s consent acts as a veto of donation intentions and attenuates the effect of regulation on actual donations. More specifically, PC increases WTD one’s own and relatives’ organs in countries where no family consent is required. Consistently, we find that family consent attenuates the influence of regulatory environment on actual donations. The effect is driven by the influence of family discussions which increased WTD, and in combination with presumed consent translated into higher organ donation rates."

Wednesday, July 22, 2020

More applications, from fewer applicants per position in Vascular Surgery residencies

Trends in the 10-year history of the vascular integrated residency match: More work, higher cost, same result
Katherine K.McMackin MD, Francis J.Caputo MD, Nicholas G.Hoell MD, JoseTrani MD, Jeffrey P.Carpenter MD, Joseph V.Lombardi MD
Journal of Vascular Surgery, Volume 72, Issue 1, July 2020, Pages 298-303

"During the last 10 years, the number of vascular surgery integrated residency spots rose from 9 to 60 per year. Most programs offer one spot per year; none offer more than two. The average number of applications received by programs rose from 17 applications in 2008 to 63.8 in 2017. The average rank list depth needed by programs to fill the spots has not increased (range, 2.5-5.1; standard deviation, 0.73). The proportional depth of the applicant pool decreased from 4.6 U.S. and Canadian applicants for every one residency spot in 2008 to 1.7 applicants for every one residency spot in 2017. Applicant quality metrics were available for 2 years (2014 and 2016). Step 1 scores (237/239), Step 2 scores (250/250), research experiences (3.7/4.2), and volunteer experiences (5.9/5.5) remained nearly unchanged. The number of contiguous ranks for matched applicants remained stable (12.3/12.8).

The current system promotes multiple inefficiencies, resulting in application glut. Fewer applicants are flooding programs with an increasing number of applications. More money is being spent on Electronic Residency Application Service applications without changes in the number needed to rank by applicants or programs to achieve a match. There is no improvement in the quality of the applicant. Should these trends continue, they represent an unsustainable model for resident selection."

Tuesday, July 21, 2020

Computer security and defending against insider attacks

Twitter suffered a very public attack on Wednesday, apparently only for the purpose of a bitcoin scam. But the scope of the attack raises all sorts of security questions, including how to guard against insider attacks.

Here's the NY Times story:
A Brazen Online Attack Targets V.I.P. Twitter Users in a Bitcoin Scam
In a major show of force, hackers breached some of the site’s most prominent accounts, a Who’s Who of Americans in politics, entertainment and tech.
By Sheera Frenkel, Nathaniel Popper, Kate Conger and David E. Sanger

"Twitter’s investigation into the breach revealed that several employees who had access to internal systems had their accounts compromised in a “coordinated social engineering attack,” a spokesman said, referring to attacks that trick people into giving up their credentials. The attackers then used Twitter’s internal systems to tweet from high-profile accounts like Mr. Biden’s."

Twitter tweeted the following:

Twitter Support
We detected what we believe to be a coordinated social engineering attack by people who successfully targeted some of our employees with access to internal systems and tools.
7:38 PM · Jul 15, 2020·Twitter Web App
If there was ever a time in the past at which corporate computer security was merely a matter of building a wall between outsiders and inside information, that time is now well past.  This twitter attack was, at least in some respects, an insider attack, by someone with access to Twitter employees' access. Whether that access was obtained by fooling the employees, coercing them, or co-opting them is less important than the fact that, apparently, some (and perhaps many) twitter employees had access of a sort that let them do things that they would never have to do as part of their jobs.

(Here's an earlier post which includes a link to a story in which a twitter employee was apparently also working for Saudi intelligence: Saturday, March 14, 2020 Organizations' security policies in the news)

Regardless of how this recent attack was carried out, I'm sure that twitter is now looking hard at internal access and starting to think about how to avoid insider attacks by limiting the access of many employees.

As companies adopt "counterintelligence" security policies of this sort, there is a hidden cost, because openness promotes fruitful cooperation and problem solving, not just security vulnerabilities.

Monday, July 20, 2020

SCIENTISTS FOR SCIENCE-BASED Policy (even more, and again)--open letter

Here's a self explanatory email:

Dear NAS Colleagues,

We are deeply appreciative of your decision in spring 2018 to sign the Statement to Restore Science-Based Policy in Government. website https://scientistsforsciencebasedpolicy.org/ 

We are writing now to update you.  This past month we contacted members newly elected in 2019 and 2020, asking if they would like to add their names to the Statement. Although much has happened in the past two years, we decided to keep the text of the Statement  unchanged.  Its wording remains as relevant today as earlier, perhaps even more so.

We are pleased to report that about 62 percent of the new members have signed, raising the total number to over 1220.  We are now distributing the explanatory statement below to selected journalists. This statement is also available at

We would be happy if you would disseminate this information as you think appropriate.  Moreover, should you be in touch with members who have not yet signed the Statement and wish to do so, please have them email us and we will add their names.


Charles Manski, Ben Santer, and Ray Weymann,  NAS members

Here's the closing paragraph of the original (and reissued) letter:

"Scientific evidence and research should be an important component of policymaking. We therefore call on the Federal Government to maintain scientific content on publicly accessible websites, to appoint qualified personnel to positions requiring scientific expertise, to cease censorship and intimidation of Government scientists, and to reverse the decision to withdraw the United States from the Paris Agreement."

And here are the opening paragraphs of the historical context document:

"Pandemic Exposes Fatal Consequences of Dismissing Scientific Expertise
1,220 members of the National Academy of Sciences call for science-based policy
July 16, 2020

“Ignorance and wishful thinking are not effective response strategies in the face of a global pandemic or global climate change,” said Dr. Ben Santer, one of three co-organizers of this open letter. “We need to restore science-based policy in government – but we also need to ensure that science is valued in public discourse and in all levels of our educational system.”

"This call for restoring science to policymaking has a several-year history. In the summer of 2016, while campaigning for the Republican nomination for the U.S. Presidency, Donald J. Trump publicly announced his intention to withdraw the United States from the Paris Climate Accord. This announcement – and Mr. Trump’s public dismissal of climate science as “a hoax” – prompted four members of the U.S. National Academy of Sciences to write an open letter (http://responsiblescientists.org). The letter’s purpose was to affirm the reality and seriousness of human-caused climate change. It pointed out the severe and long-lasting consequences of an eventual U.S. withdrawal from the Paris Climate Accord. At the time of its publication in September 2016, the open letter had 378 NAS signatories."