Friday, September 10, 2021

Matching theory in the September issue of Games and Economic Behavior

 The September 2021 issue of Games and Economic Behavior (Volume 129, Pages 1-590) has five papers on matching theory.

In the order in which they appear:

An improved bound to manipulation in large stable matches  by Gustavo Saraiva

https://doi.org/10.1016/j.geb.2021.05.005Get rights and content

Abstract: This paper builds on Kojima and Pathak (2009)'s result of vanishing manipulability in large stable mechanisms. We show that convergence toward truth-telling in stable mechanisms can be achieved much faster if colleges' preferences are independently drawn from an uniform distribution. Another novelty from our results is that they can be applied to competitive environments in which virtually all vacancies end up being filled. So this paper adds evidence to the fact that, though stable matching mechanisms are not entirely strategy-proof, in practice, when the number of participants in the market is sufficiently large, they can be treated as being effectively strategy-proof.

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How lotteries in school choice help to level the playing field by Christian Basteck, Bettina Klaus, Dorothea Kübler

https://doi.org/10.1016/j.geb.2021.05.010Get rights and content

Abstract: School authorities in the UK and the US advocate the use of lotteries to desegregate schools. We study a school choice mechanism employed in Berlin where a lottery quota is embedded in the immediate acceptance (IA) mechanism, and compare it to the deferred acceptance mechanism (DA) with a lottery quota. In both mechanisms, some seats are allocated based on academic achievement (e.g., grades), while seats in the lottery quota are allocated randomly. We find that, in theory, a lottery quota strengthens truth-telling in DA by eliminating non-truth-telling equilibria. Furthermore, the equilibrium outcome is stable for DA with a lottery but not for IA with a lottery. These predictions are borne out in the experiment. Moreover, the lottery quota leads to more diverse school populations in the experiment, as predicted. Students with the lowest grades profit more from the introduction of the lottery under IA than under DA.

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Substitutes and stability for many-to-many matching with contracts  by Keisuke Bando, Toshiyuki Hirai, Jun Zhang

https://doi.org/10.1016/j.geb.2021.07.002Get rights and content

Abstract:We examine the roles of (slightly weakened versions of) the observable substitutability condition and the observable substitutability across doctors condition of Hatfield et al. (2021) in many-to-many matching with contracts. We modify the standard cumulative offer algorithm to find stable outcomes and prove new results on the existence of stable outcomes. It is remarkable that size monotonicity at the offer-proposing side is essential for the existence result under observable substitutability across doctors.

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Slot-specific priorities with capacity transfers  by Michelle Avataneo and BertanTurhan

https://doi.org/10.1016/j.geb.2021.07.005

Abstract: In many real-world matching applications, there are restrictions for institutions either on priorities of their slots or on the transferability of unfilled slots over others (or both). Motivated by the need in such real-life matching problems, this paper formulates a family of practical choice rules, slot-specific priorities with capacity transfers (SSPwCT). These rules invoke both slot-specific priorities structure and transferability of vacant slots. We show that the cumulative offer mechanism (COM) is stable, strategy-proof and respects improvements with regards to SSPwCT choice rules. Transferring the capacity of one more unfilled slot, while all else is constant, leads to strategy-proof Pareto improvement of the COM. Following Kominers' (2020) formulation, we also provide comparative static results for expansion of branch capacity and addition of new contracts in the SSPwCT framework. Our results have implications for resource allocation problems with diversity considerations.

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Stability in sequential matching with incomplete information by Fanqi Shi

https://doi.org/10.1016/j.geb.2021.07.001Get rights and content

Abstract: I study a two-period matching model where one side of the market (e.g. workers) have an option to invest and delay matching in the first period. Investment increases each agent's matching surplus in the second period, by a magnitude of the worker's investment ability in the match pair. Assuming each worker's investment ability is her private information that unfolds in the second period, I define a notion of sequential stability, and show that the set of sequentially stable outcomes is a superset of the complete information stable outcomes. Moreover, with transferable utility, as long as the cost of delay coincides on the same side of the market, efficient investment occurs in any sequentially stable outcome. When every agent shares the same cost of delay, efficient investment also occurs in any sequentially stable outcome with non-transferable utility. My analysis suggests that efficient investment is a robust prediction in sequential matching markets.



Thursday, September 9, 2021

Kidney exchange, in Microeconomic Insights

 The team at Microeconomic Insights has published an easy to read summary of my just published paper with Itai Ashlagi in the September issue of Management Science:

Kidney Exchange: An Operations Perspective

"No country is presently able to supply all the kidney transplants required by its population, and most people with kidney failure will die without receiving a transplant. Kidney exchange is a way to increase the number of transplants by allowing incompatible patient-donor pairs to exchange kidneys. For logistical reasons, early exchanges involved just two patient-donor pairs, but the rise in donors without a particular recipient in mind has enabled long chains of non-simultaneous transplants. However, barriers between kidney exchange programs, both within and across countries, continue to make it difficult to find matches for some patient-donor pairs. Breaking down these barriers will be challenging, but the potential rewards are large—both in terms of lives saved and reduced healthcare costs."




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Here's a link to the original paper:

1. Itai Ashlagi and Alvin E. Roth, “Kidney Exchange:  an Operations Perspective,” Management Science, September 2021, Volume 67, Issue 9, September 2021, Pages 5301-5967, iii-iv, https://pubsonline.informs.org/doi/10.1287/mnsc.2020.3954 

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Here's a video of a lecture I gave about the paper in June to an INFORMS audience, starting at minute 2:55.



Wednesday, September 8, 2021

Participating in a Covid challenge trial: a participant's experience

 The WSJ's Jenny Strasburg has another story on British challenge trials of Covid-19:

Researchers Infect Volunteers With Coronavirus, Hoping to Conquer Covid-19. So-called challenge trials have long been used to study infections, but so far only the U.K. is doing them for Covid-19   By Jenny Strasburg

"On March 8, 23-year-old Jacob Hopkins, a U.K. university student, watched researchers enter his quarantine room’s airlocked entrance at London’s Royal Free Hospital. They wheeled a cart carrying a big red box, like a picnic cooler, labeled “biohazard.”

...

"A few days after the virus was dripped into his nose, he was shivering with a mild case of Covid-19, with the antiviral remdesivir pumped through a thin tube inserted into his arm. He spent 19 days in quarantine and said he felt fully recuperated a month later. He will ultimately be paid about £6,000, equivalent to $8,300, for that time, a year of follow-up tests and phone calls, and a parallel study he agreed to. Trial payments are based on U.K. living wages and go through ethical review."

...

"All volunteers are 18 to 30 years old and screened for known risk factors. They are isolated in quarantine suites with full-time medical care and specialized air systems to contain the virus. Researchers hope to publish peer-reviewed initial findings from the first phase of the challenge trials by this autumn.

...

"Researchers hope trial data will shed light on the durability of immune protection and how Covid-19 affects breathing, heart function, smell and concentration even before symptoms show. They say the model could test new vaccines and treatments head-to-head, eliminating weaker candidates before expensive, large-scale trials. Transmission data could help authorities prioritize who gets booster doses.

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As an observer of repugnant/controversial transactions, I've been following the challenge trial discussion, including in particular about appropriate payments for participants.  There's a part of the medical ethics literature that worries that payments to volunteers might be 'coercive,' particularly to poor volunteers, and that payments should therefore be as small as possible, e.g. minimum wage payments for time spent, and that some things (such as risk) should not be compensated. My colleagues and I have been among those pointing out that there can also be ethical (as well as practical) issues involved in paying too little (or in providing too little post-trial medical care and insurance).


Here are some earlier posts focusing on articles I've coauthored about compensation for participation in challenge trials:

Thursday, October 29, 2020

Paying participants in challenge trials of Covid-19 vaccines, by Ambuehl, Ockenfels, and Roth

"we note that increasing hourly pay by a risk-compensation percentage as proposed in the target article provides compensation proportional to risk only if the risk increases proportionally with the number of hours worked. (Some risky tasks take little time; imagine challenge trials to test bulletproof vests.) "


Tuesday, September 7, 2021

Covid reduced transplants worldwide (but relatively little in the U.S.)

 The Covid pandemic reduced transplants, more in some countries than in others.  Here's a survey from  the Lancet, covering 22 countries (with more authors than countries):

COVID-19 pandemic and worldwide organ transplantation: a population-based study by Olivier Aubert, MD Daniel Yoo, MPH Dina Zielinski, PhD Emanuele Cozzi, MD Massimo Cardillo, MD Michael Dürr, MD Beatriz Domínguez-Gil, MD Elisabeth Coll, MD Margarida Ivo Da Silva, MD Ville Sallinen, MD Karl Lemström, MD Karsten Midtvedt, MD Camilo Ulloa, MD Franz Immer, MD Annemarie Weissenbacher, MD Natalie Vallant, MD Nikolina Basic-Jukic, MD Kazunari Tanabe, MD Georgios Papatheodoridis, PhD Georgia Menoudakou, MSc Martin Torres, MD Carlos Soratti, MD Daniela Hansen Krogh Carmen Lefaucheur, MD Gustavo Ferreira, MD Helio Tedesco Silva Jr, MD David Hartell, MA John Forsythe, MD Lisa Mumford, MSc Peter P Reese, MD François Kerbaul, MD Christian Jacquelinet, MD Serge Vogelaar, MD Vassilios Papalois, MD Alexandre Loupy, MD 

"In this population-based, observational, before-and-after study, we collected and validated nationwide cohorts of consecutive kidney, liver, lung, and heart transplants from 22 countries. Data were collected from Jan 1 to Dec 31, 2020, along with data from the same period in 2019. The analysis was done from the onset of the 100th cumulative COVID-19 case through to Dec 31, 2020. We assessed the effect of the pandemic on the worldwide organ transplantation rate and the disparity in transplant numbers within each country.

...

"Transplant activity in all countries studied showed an overall decrease during the pandemic. Kidney transplantation was the most affected, followed by lung, liver, and heart."

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Here's a figure of percentage reduction in transplants, overall and by organ, for each country.  The U.S. performance was relatively good.




Monday, September 6, 2021

Contested forms of marriage: child marriage (and signaling), bride exchange (watta satta), and capture (ala kachuu in Kyrgyz, zij poj niam in Hmong)

 Recent changes in child marriage laws in some U.S. states have reminded me that it is just one of many forms of contested marriage around the world.

Here's an NBC report on child marriage laws in the U.S.:

A child marriage survivor helped ban the practice in New York, but 44 states still allow it Maya Brown

"Child marriage is when someone under the age of 18 becomes legally married to an adult. Such minors, more likely girls than boys, are often forced into marriage because of socioeconomic factors by families who want to minimize their economic burden or earn income as a result of the marriage, according to UNICEF. Religious and cultural norms also contribute to its ongoing practice.

...

"As of 2020, there were an estimated 285 million child brides in South Asia. About 59 percent of girls are married before the age of 18 in Bangladesh, 27 percent in India and 18 percent in Pakistan, according to data from Girls Not Brides. The Women’s Refuge Commission says South Asian families force their daughters into child marriage as it is perceived to be the best means to provide economic and physical security.

"Even though almost half of all women in South Asia aged 20-24 reported being married before the age of 18, the rates of child marriage are currently decreasing in the region. Amin stressed that child marriage does not happen only to South Asian women, but it also affects women in other countries.

"In Latin America and the Caribbean, about 1 in 4 women are married before 18. Most of the top 20 countries with the highest prevalence rates of child marriage are in Africa, with Niger having the highest child marriage rate in the world. In west and central Africa, about 41 percent of girls in the region marry before reaching the age of 18.

"It also greatly affects women in the U.S., as approximately 40 children are married each day in America. Nearly 300,000 minors under the age of 18 were legally married in the U.S. from 2000 to 2018, according to a recent study. States with the highest per-capita rates of child marriage include Arkansas, Idaho, Kentucky, Nevada and Oklahoma."

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Here's a recent NBER paper exploring an intervention, based on the idea that early marriage may signal a girl is a traditional type (not a modern type), and that other ways of signaling this might reduce the incentive to marry early:

A Signal to End Child Marriage: Theory and Experimental Evidence from Bangladesh by Nina Buchmann, Erica M. Field, Rachel Glennerster, Shahana Nazneen & Xiao Yu Wang.  WORKING PAPER 29052, DOI 10.3386/w29052,  July 2021

Abstract: Child marriage remains common even where female schooling and employment opportunities have grown. We introduce a signaling model in which bride type is imperfectly observed but preferred types have lower returns to delaying marriage. We show that in this environment the market might pool on early marriage even when everyone would benefit from delay. In this setting, offering a small incentive can delay marriage of all treated types and untreated non-preferred types, while programs that act directly on norms can unintentionally encourage early marriage. We test these theoretical predictions by experimentally evaluating a financial incentive to delay marriage alongside a girls’ empowerment program designed to shift norms. As predicted, girls eligible for the incentive are 19% less likely to marry underage, as are nonpreferred type women ineligible for the incentive. Meanwhile, the empowerment program was successful in promoting more progressive gender norms but failed to decrease adolescent marriage and increased dowry payments.

Update: published at American Economic Review 2023, 113(10): 2645–2688 https://doi.org/10.1257/aer.20220720

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Then there's bride exchange, apparently still extant in Pakistan and Afganistan: here's a paper from the AER that interprets it as a kind of hostage exchange...

Jacoby, Hanan G., and Ghazala Mansuri. 2010. "Watta Satta: Bride Exchange and Women's Welfare in Rural Pakistan." American Economic Review, 100 (4): 1804-25.

Abstract: Can marriage institutions limit marital inefficiency? We study the pervasive custom of watta satta in rural Pakistan, a bride exchange between families coupled with a mutual threat of retaliation. Watta satta can be seen as a mechanism for coordinating the actions of two sets of parents, each wishing to restrain their son-in-law. We find that marital discord, as measured by estrangement, domestic abuse, and wife's mental health, is indeed significantly lower in watta satta versus "conventional" marriage, but only after accounting for selection bias. These benefits cannot be explained by endogamy, a marriage pattern associated with watta satta. 

...

"In traditional societies, where women’s formal legal rights are often weak, divorce is strongly stigmatized, and there is a high premium on female virginity, bargaining power can shift radically in favor of the man once the woman commits herself to marriage. This fact should have implications for the form of the marriage “contract”; in particular, we would expect its ex ante provisions to reflect the interests of the wife and her family in deterring or mitigating ex post malfeasance on the part of the husband.

"In this paper, we argue that exchange marriage in rural Pakistan can play just such a role. Bride exchange, known locally as watta satta (literally, “give-take”), usually involves the simultaneous marriage of a brother-sister pair from two households. Remarkably, watta satta accounts for about a third of all marriages in rural Pakistan. Watta satta is more than just an exchange of daughters, however; it also establishes the shadow of mutual threat across the marriages. As the watta bride quoted above expresses so succinctly, a husband who mistreats his wife in this arrangement can expect his brother-in-law to retaliate in kind against his sister.

...

"in the end, the evidence is compelling that the peculiar institution of watta satta, with its mutual threat of reciprocity, protects the welfare of women in rural Pakistan."

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Of course, bride exchange occurs for other reasons than hostage exchange.  A colleague of mine reports that his grandparents, who emigrated from India to the U.S. in the 1960's, were married in a bride exchange between two brother-sister pairs, whose purpose was to remove the requirement of dowries.  And I know of stories in which a potential bride was doing essential household tasks (e.g. taking care of a disabled brother) and a bride exchange allowed her to marry without those tasks becoming neglected.

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And finally, let's not forget marriage by capture, still extant in central Asia, and within living memory a cause of cultural conflict among Hmong immigrants to California and Minnesota among other places.

Here's a very recent story from the Guardian:

Kidnapped, raped, wed against their will: Kyrgyz women’s fight against a brutal tradition. At least 12,000 women are still abducted and forced into marriage every year in Kyrgyzstan. But pressure is growing to finally end the medieval custom.  by Mauro Mondello, 30 Aug 2021

"Known as ala kachuu (“take and run”), the brutal practice of kidnapping brides has its roots in medieval times along the steppes of Central Asia, yet persists to this day. It has been banned in Kyrgyzstan for decades and the law was tightened in 2013, with sentences of up to 10 years in prison for those who kidnap a woman to force her into marriage (previously it was a fine of 2,000 soms, worth about $25).

"The new law has not curtailed the practice, however, and prosecutions are rare. Nevertheless, according to the human rights organisation Restless Beings: “This is a significant development, in that prior to this the sentence for stealing livestock was considerably more than that for ala kachuu.”

“A happy marriage begins by crying,” goes one Kyrgyz proverb, and those tears are of anger and terror at the start of a marriage for ala kachuu brides.

"Ala kachuu is practised in all the countries of Central Asia, but it is especially common in the rural areas of post-Soviet Kyrgyzstan, a predominantly Muslim nation of about 6 million people. During Soviet rule, the custom was rare and parents generally arranged marriages.

"Data from the Women Support Center, an organisation that fights for gender equality in the country, indicates that at least 12,000 marriages take place, and are consummated, every year against the will of the bride. (The figure is from a 2011 report and believed to be an underestimate). Men kidnap women, they say, to prove their manhood, avoid courtship (considered a tedious waste of time) and save the payment of the kalym, or dowry, which can cost the groom up to $4,000 (£3,000) in cash and livestock.

"After the ala kachuu, which in some cases can be a consensual “kidnapping” when a couple wishes to speed up the process of marriage, the brides are taken to the house of the future husband. The in-laws welcome the woman and force her to wear the jooluk, a white shawl that signifies submission to the bride’s new family. Then comes the wedding. About 80% of the girls kidnapped accept their fate, often on the advice of their parents.

"According to data from the Unicef office in Bishkek the percentage of girls aged 15 to 19 who become pregnant in Kyrgyzstan is among the highest in the region, while 13% of marriages take place before the age of 18, despite it being illegal. "

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And of course courts think differently of immigrant customs and local customs:

Hmong 'marriage by capture' in the United States of America and ukuthwala in South Africa : unfolding discussions  by Lea Mwambene  Published Online:1 Jan 2020https://doi.org/10.25159/2522-3062/5981https://hdl.handle.net/10520/ejc-cilsa-v53-n3-a6 Comparative and International Law Journal of Southern AfricaVol. 53, No. 3

Abstract: 'Marriage by capture' among the Hmong people in the United States of America and ukuthwala in South Africa both take the form of the mock abduction of a young woman for the purpose of a customary marriage. The noteworthy point about these two customary marriage practices is that, although Hmong marriage by capture takes place in the context of a minority community in a liberal state, and ukuthwala occurs in a postcolonial state, courts in these jurisdictions convert these marriage practices to the common law offences of rape, assault, and abduction. This article reflects on the accused-centred approach in the case of People v Moua, in which the court invoked the cultural defence, and the victim-centred approach in Jezile v S, which severed cultural values from the rights of the woman. It questions whether the two communities in question, in their respective liberal and postcolonial settings, influence the attitudes of the courts in cases involving rape, assault, and abduction charges. The main argument proffered is that both approaches may encourage communities to continue marriage abduction practices without bringing them to the attention of investigative organs, with adverse human rights implications for the women and girls affected. The ultimate purpose of this conversation, therefore, is to show how the approaches of the courts to the recognition or non-recognition of these customary practices affect the rights of girls and women who encounter institutions of law that alienate people belonging to minority cultural groups, and often perpetuate injustice.

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and 

Deirdre Evans-Pritchard & Alison Dundes Rentein, The Interpretation and Distortion of Culture: A Hmong Marriage by Capture Case in Fresno, California, 4 S. CAL. Interdisc.L. J. 1 (1994)

Different cultural practices and social norms can promote coordination failures and misunderstandings of the gravest sorts: here's a 1988 story from the Los Angeles Times, which starts with the same Fresno case as the above article, and goes on to a very different Minnesota case.

Immigrant Crimes : Cultural Defense--a Legal Tactic  BY MYRNA OLIVER, JULY 15, 1988

"Kong Moua, a Hmong tribesman from the hills of Laos, drove to the Fresno City College campus looking for his intended bride. Locating her at her job in the student finance office, he spirited her away to his cousin’s house.

"Kong Moua called it zij poj niam, or “marriage by capture,” in his culture an accepted form of matrimony akin to elopement.

"However, his “bride,” also a Hmong but more assimilated into American culture, called it kidnaping and rape. She also called the police.

"Kong Moua’s lawyer, in negotiating a plea to the lesser charge of false imprisonment, introduced literature documenting the Hmong marital customs.

"After reading the material, the judge sentenced Kong Moua to 120 days in jail and fined him $1,000, with $900 of that going to the victim as reparations--far less than the state prison term he could have gotten for kidnaping and rape.

...

"In another Hmong “marriage by capture” case, this one in St. Paul, Minn., Ramsey County Assistant Attorney Daniel Hollihan, decided not to take the case to trial.

"With the help of St. Paul’s Southeast Asian Refugee Study Project, Hollihan learned that in the Hmong “marriage by capture,” the woman or girl, often under 15 years of age, must protest her capture by insisting “No, no, I am not ready” to be considered virtuous and desirable. If the man does not take her by the hand and lead her off to his own home, he is considered too weak to be a husband.

"The prosecutor decided that it would be almost impossible to convince a jury that the girl really meant “no” and had been taken away against her will and raped. So he opted for a plea bargain.

“I went to the victim’s family and said, ‘How would you resolve this in the old country?’ ” Hollihan said.

“The victim’s aunt, who spoke English, told me $3,000 and no jail, $2,000 and 60 days, or $1,000 and 90 days, to restore the family honor and pride,” he said.

"The defendant was allowed to plead guilty to sexual intercourse with a child under the age of 12, and fined $1,000 with no jail time."

Sunday, September 5, 2021

Australia and England swap millions of vaccine doses

Barter can increase efficiency. The Financial Times has the story:

Australia strikes deal to ‘swap’ 4m vaccine doses with UK  by William Langley and Oliver Barnes 

"The UK will send 4m Covid-19 vaccine doses to Australia in a swap deal aimed at accelerating Canberra’s stuttering rollout and bolstering British supplies later in the year when ministers are pushing for a booster campaign. 

"The first batch of 292,000 BioNTech/Pfizer doses will arrive in Australia in the coming days, with the remainder due by the end of the month, Prime Minister Scott Morrison said on Friday. 

"Australia will return an equivalent 4m doses before the end of the year, according to the UK health department.

"The deal is designed to speed up Australia’s vaccination rollout, which has been one of the slowest in the world, and Morrison said it would allow the government to bring forward its prospective reopening date.

"It reflects the UK’s calculation that it does not currently need all its stockpiled doses, which expire in a matter of months if not used, while allowing London to boost supplies later this year in anticipation of a broad booster campaign and the vaccination of 12 to 15-year-olds."


Saturday, September 4, 2021

Adam Smith and kidney exchange, by Walter Castro and Julio Elias

 Here's a blog post with supportive quotes from Adam Smith (who if he had thought specifically about kidney exchange in The Theory of Moral Sentiments (1759) would have been not quite 200 years in advance of the first successful kidney transplant (in 1954 by Joseph Murray, between identical twins...)

Adam Smith and Kidney Exchange by Walter Castro and Julio J. Elías

"Castro and Elías return with more Smithian insights into the logic of altruism and the design of kidney exchange markets."

Friday, September 3, 2021

Long-Term Survival after Kidney Transplantation by Hariharan, Israni, and Danovitch in the NEJM

 Here's a review article from the New England Journal of Medicine, documenting the increasing rates of long term kidney transplant outcomes, in terms of both patient and graft survival. (Kidney exchange has played a role.)

Long-Term Survival after Kidney Transplantation  by Sundaram Hariharan, M.D., Ajay K. Israni, M.D., and Gabriel Danovitch, M.D.

Graft and Patient Survival after Kidney Transplantation in the United States.

Shown are Kaplan–Meier estimates of patient survival (Panels A and B) and graft survival (Panels C and D) after transplantation of grafts from living donors (Panels A and C) and deceased donors (Panels B and D), with the data grouped in 4-year cohorts from 1996 to 2015. There were gradual improvements in patient and graft survival from the 1996–1999 period to the 2012–2015 period.


Here are the concluding paragraphs:

"Improvement in long-term survival after kidney transplantation has been gratifying, despite unfavorable changes in donor and recipient risk factors. Continuation of this trend will require a multipronged approach that addresses coexisting conditions before transplantation, health literacy, access to caregivers, and, especially among racial or ethnic minority and young transplant recipients, adherence to therapy. Innovative noninvasive biomarkers to diagnose and prevent acute rejection, adoptive T-cell therapy for post-transplantation viral infections, and newer therapies for T-cell–mediated rejection, antibody-mediated rejection, and desensitization are under investigation.

"Nephrologists and primary care physicians must be adequately trained to care for kidney transplant recipients. A silver lining of the Covid-19 pandemic may be the incorporation of telemedicine into routine care to facilitate access to transplantation and post-transplantation care, particularly for older patients and those in underserved and geographically remote communities. The discontinuation of insurance coverage for long-term immunosuppressive medications for kidney transplant recipients in the United States was an unnecessary impediment to long-term survival, for which patients and society paid a heavy price; the 2020 approval of lifelong health care coverage of these medications for transplant recipients in the United States is a victory that will pave the way toward further improvements in long-term survival."

Thursday, September 2, 2021

Global Kidney Chains in PNAS by Nikzad, Akbapour, Rees and Roth

 Here's an article about extending kidney exchange globally. It's published as an open access article, so you can find the whole paper at the link.

Global kidney chains, by Afshin Nikzad, Mohammad Akbarpour, Michael A. Rees, and  Alvin E. Roth, PNAS September 7, 2021 118 (36) e2106652118; https://doi.org/10.1073/pnas.2106652118


Significance: Kidney failure is among the leading causes of death worldwide, and the best treatment is transplantation. However, transplants are in short supply because of shortfalls of transplantable organs and of finances. In the United States and some other countries, kidney exchange chains have emerged as a way to increase the number of transplants; patients who have a willing donor but cannot receive that donor’s kidney can each receive a compatible kidney from another patient’s intended donor. Such programs are much better developed within the borders of wealthy countries, which is of little help to patients in countries with limited kidney transplantation or exchange. This paper proposes and analyzes a way to extend kidney exchange chains to share the benefits globally.


Abstract: Kidney failure is a worldwide scourge, made more lethal by the shortage of transplants. We propose a way to organize kidney exchange chains internationally between middle-income countries with financial barriers to transplantation and high-income countries with many hard to match patients and patient–donor pairs facing lengthy dialysis. The proposal involves chains of exchange that begin in the middle-income country and end in the high-income country. We also propose a way of financing such chains using savings to US health care payers.

...

"Concluding Remarks: Since the beginning of the twenty-first century, kidney exchange at scale has developed from a largely academic idea initially implemented at a small scale (5, 37) to a standard mode of transplantation in the United States (with well over 1,000 exchange transplants in 2019) and in several other countries. This has been an important development, with many milestones along the way including, crucially, developments in the design and implementation of kidney exchange chains. However, these accomplishments have been victories in a war that we are losing. At the turn of the century, there were in the neighborhood of 40,000 patients on the US waitlist for deceased donor organs, and today, there are close to 100,000.‡‡ The situation is similar elsewhere in the wealthy world. Over the same period, there has been a growth of kidney disease as a cause of death around the world (as developing countries have made progress in combating infectious disease), and there have begun to be high-quality transplant centers in middle-income as well as in rich countries, which nevertheless face obstacles—including important financial obstacles—to increasing the number of transplants they are able to deliver.§§

"Before the development of kidney exchange, the organization of transplantation developed largely within the national boundaries of wealthy countries. It was primarily focused on deceased donor transplants, and the scarcity of organs meant that the concentration of effort within single countries did not have a large impact on the total number of transplants achieved. (There are well-established efforts to share deceased donor kidneys across national borders in limited circumstances.) With the growth of kidney exchange, there are now some preliminary explorations of coordinating across borders between countries with existing kidney exchange programs, primarily concentrating on looking for exchanges between hard to match pairs who have been left unmatched in the within-country kidney exchange. GKE opens up this possibility to a much larger part of the world, including countries in which unmatched patient–donor pairs may have had financial rather than immunological barriers, and so, may be easier to match with hard to match pairs. Additionally, because kidney exchange chains have amplified kidney exchange wherever they have been implemented, global exchange chains offer a way to bring these advantages to a much larger group of patients and donors.¶¶

"While Medicare aims to insure all Americans against kidney disease, the same cost savings described here could be employed to fund care for foreign patients who are uninsured, including those who are undocumented immigrants who may not have entered the country legally (but may nevertheless be long-term residents).##

"Notice that if an international exchange works perfectly—i.e., when all of the patients and donors involved have successful surgeries, have excellent follow-up care, and are restored to active, long-lasting good health—then it will be easy to see the exchange as just another example of the success of standard kidney exchange in which all patients are from the same country. However, if the pair from the developing country was to return home and have bad health outcomes, it would look a lot like badly arranged black market transactions, which are justly condemned. So, to make kidney exchange work between developed and developing countries, exceptional care will have to be delivered to the developing country donors and patients, particularly since patients in poor countries—like their compatriots who have never suffered from kidney disease—can be expected to have somewhat worse health outcomes than otherwise comparable people in rich countries, no matter what efforts are made to give them the best possible postoperative care. International exchange may also require increased vigilance, compared with domestic exchange, to ensure that donors are not coerced or otherwise exploited. Consequently, the first element of a successful design for GKC is the choice of reliable international partners able to provide excellent care for patients and donors, both prospectively and postoperatively.

"The other three design elements proposed and explored in this paper involve starting a chain in a foreign country and having a bridge donor continue it in the United States; using a LIFO queue policy on the pool of patients assembled by, for example, a coalition of self-insured companies responsible for paying for their care; and having those savings finance the otherwise unfunded additional costs (compared with an entirely domestic chain) in both countries. As we have shown, such a program could operate at a significant scale, comparable with the number of domestic patients presently beginning lengthy dialysis annually. GKCs thus appear to present a scalable approach to cross-border kidney exchange and to increasing the availability of transplantation globally. They have the potential to become at least a first step toward providing a global solution to the global problem of kidney failure."

 

Wednesday, September 1, 2021

Redesigning the market for American medical residencies

 The medical community has spent a good deal of effort over the past two years conferring about difficulties in the transition from medical school to residency, i.e. in transiting from what is called undergraduate medical education (in medical school, recognized with a degree) to graduate medical education (working in a hospital, recognized by Board certification in some medical specialty).  

The resulting document, below, represents a lot of work by a lot of people, and is worth a close look. (It's long: 276 pages, three dozen or so more or less specific recommendations, public comments, etc.). 

I'll have more to say about some specifics in future posts, in due time. 

The Coalition for Physician Accountability’s Undergraduate Medical Education-Graduate Medical Education Review Committee (UGRC): Recommendations for Comprehensive Improvement of the UME-GME Transition


"Overview: In 2020, the Coalition for Physician Accountability (Coalition) formed a new committee to examine the transition from undergraduate medical education (UME) to graduate medical education (GME). The UME-GME Review Committee (the “UGRC” or the “Committee”) was charged with the task of recommending solutions to identified challenges in the transition. These challenges are well known, but the complex nature of the transition together with the reality that no single entity has responsibility over the entire ecosystem has perpetuated the problems and thwarted attempts at reform.

"Using deliberate and thoughtful methods, the UGRC spent 10 months exploring, unpacking, discussing, and debating all aspects of the UME-GME transition. The Committee envisioned a future ideal state, performed a rootcause analysis of the identified challenges, repeatedly sought stakeholder input, explored the literature, sought innovations being piloted across the country, and generated a preliminary set of potential solutions to the myriad problems associated with the transition. Initial recommendations were widely released in April 2021, and feedback was obtained from organizational members of the Coalition as well as interested stakeholders through a public  call for comment. This feedback was instrumental to refining, altering, and improving the recommendations into their final form. The UGRC also responded to feedback by consolidating similar recommendations, organizing them into more cogent themes, and sequencing them to guide implementation. "

Tuesday, August 31, 2021

Challenge trials for Covid-19 Delta variant

 Before the development of the first Covid vaccines, there was a good deal of discussion about the appropriateness of testing vaccines with human challenge trials, i.e. with tests in which volunteers were deliberately exposed to Covid so that the vaccine effectiveness could be more readily assessed.  Now, with the Delta variant spreading, those issues are once again live.

Only England has authorized challenge trials. Here's a story from the WSJ:

Researchers Ready Lab-Grown Covid-19 Delta Variant for Human Trials. U.K. company is growing the highly contagious variant under tight lab controls for use in challenge studies  By Jenny Strasburg

"While the rest of the world is trying to stamp out the Covid-19 Delta variant, British researchers are making progress growing a carefully controlled batch in a lab that they hope to use to infect volunteers in studies.


"The effort marks a new phase in the U.K.’s human challenge trials, the only Covid-19 studies in the world intentionally exposing participants to the virus with the goal of developing new vaccines and treatments. 
...
"Two Covid challenge trials sponsored by Imperial College London and the University of Oxford started earlier this year in the U.K. They so far have exposed more than 40 healthy, young volunteers under isolated medical supervision to the original Wuhan strain that circulated widely in 2020.

"Since then, the highly transmissible Delta variant has come to dominate infections globally, rendering vaccines less effective and boosting case numbers across the U.K., U.S. and elsewhere. Delta’s fast rise led researchers and U.K. challenge-trial partner hVivo Services Ltd. to focus on trying to grow the variant in the lab.
...
"It took U.K. researchers and government advisers almost a year to plan and gain approval from a U.K. ethics committee and medicines regulators to start the controversial challenge trials for which the Delta strain could eventually be used. The government provided funding; so did the London-based Wellcome Trust, a large healthcare-focused charitable foundation.
...
"The challenge trials faced pushback from some U.K. academics and foreign researchers, as well as from some government officials, who considered them unsafe or otherwise unethical, people involved in the process say. Delays have caused friction among partners. hVivo, part of London-listed pharma-services company Open Orphan ORPH 3.08% PLC, had hoped to use the Covid-19 challenge-trial model by now to test antivirals and other products for drug companies, executives have told industry peers. A U.K. government spokesman said the pace of the challenge studies has reflected appropriate caution, and the trials have been safe.

"Challenge trials have been used for decades to study viruses and other pathogens by deliberately exposing volunteers and studying the body’s response. While scientists in the U.S. and Europe also pushed to do Covid-19 challenge studies, only the U.K. has moved forward."
**************

Monday, August 30, 2021

Symposium on Research Integrity: Replicability and outright malfeasance. November 24 in Berlin

 Research integrity has been in the news lately, concerning low levels of replicability in some kinds of research, together with more intentional (but probably/hopefully less widespread) problems.  Here's a forthcoming symposium:

Symposium on Integrity in Research

Place and time: hybrid event on November 24, 2021.

"Symposium topic: Research Integrity is a controversial topic within academia, but also in public discourse. Prominent cases of scientific misconduct capture the limelight, but recently a multitude of issues beyond the classical triad of plagiarism, falsification, and fabrication have taken center stage, many of which concern the quality and rigor of research and further challenge the trustworthiness of science. These include selective publication and file-drawer problems, various biases, as well as the general reproducibility or robustness of research results. At the same time, open, inclusive, and creative cultures of research in teams and organizations have been threatened by practices that prioritize outputs, as demonstrated by numerous examples of insufficient mentoring, unfair authorship practices, or intransparency about career progress for younger researchers. All these issues have long histories of discussions about improving scientific methods, however, views differ on how important these issues are, and whether all disciplines are affected equally. While some argue that there is only one scientific method, requiring universal standards for robust evidence, others emphasize the diversity of research cultures and the mutual criticism and learning that can result from this diversity.

"As scientific expertise becomes more important in and for the public, it becomes apparent that scientific findings are often provisional, subject to correction, and scientific experts may disagree. There are no simple either-or answers. While it seems indisputable that scientific evidence should be subject to the highest possible standards and be appropriate to the context, it is nevertheless necessary that these standards evolve as scientific methods and research questions progress. For urgent societal problems - such as pandemics - we may even be willing to lower these standards. For new problems, appropriate standards will only emerge after much experimentation and debate. The need for such constant debate is familiar to scientists, but can be disconcerting to the public. Standardization - both in the sense of setting standards and in the sense of homogenization - of research can therefore run the risk of undermining, rather than securing, the progress of knowledge. As a result, the integrity of research must remain a topic for debate, as it is expected to ensure both the robustness and innovation of research while meeting the expectations of different research cultures and the public.

"As a contested topic, research integrity encompasses a wide range of actors, platforms and organizations, policies and measures. The symposium will bring together participants from research, practice and policy to map this heterogeneous field, provide evidence of its effectiveness and analyze its (future) development.


"Keynotes and formats

"The symposium is organized as a hybrid event and will include keynotes by Professor Lorraine Daston (Max Planck Institute for the History of Science Berlin / University of Chicago) and Professor Dava J. Newman (Massachusetts Institute of Technology / MIT Media Lab).

"Other international and national experts will be invited together with the event's guests to discuss and reflect on the current state of research integrity and its future development. Interactive and inclusive formats connecting on-site participants and digital guests worldwide will ensure a sustained exchange on a topic of central importance for the future of science.

The symposium is organized in concurrence with the Einstein Foundation Berlin’s “Einstein Award for Promoting Quality in Research” that will take place later the same evening.

Registration, access and program

Participation in the symposium is free of charge. Further details on registration, access and the program of the event will be published on this page soon.

Contact  Nele Albrecht, Scientific Coordinator for Research Quality  Email: core@berlin-university-alliance.de 

Saturday, August 28, 2021

Bob Wilson's autobiography is now available on the Nobel Prize website

 Here it is: https://www.nobelprize.org/prizes/economic-sciences/2020/wilson/biographical/

"Robert B. Wilson, Biographical

"1.Overview at age 83

"After rocky early years, I had a happy youth in a small town, and then stumbled through eight years at Harvard, emerging with little sense of what to do next, until I moved to Stanford where my research thrived. A minor project on adverse selection in auctions led me to join in the nascent reconstruction of economic theory using game-theoretic models, and then later, foundational topics in game theory, all focused on the role of agents’ information and their effect on incentives. I’ve enjoyed working with PhD students and been fortunate to have superb co-authors with better skills."




Friday, August 27, 2021

OnlyFans announces then reverses a ban on explicit sexual content

 Here's a story from the Guardian, following the reported decision of the website OnlyFans to ban certain sexually explicit content, and then another reversing that announcement:

OnlyFans ban on sexually explicit content will endanger lives, say US sex workers, by Kari Paul

"American sex workers say subscription website OnlyFans’ decision to ban “sexually explicit” content will threaten their livelihoods, drive more of the industry underground, and ultimately endanger lives.

“They are taking away our safe spaces,” said Jane, an activist and OnlyFans creator who asked to be identified only by her first name. “Nobody wants to protect us.”

...

"Activists say the banning of pornographic content will push more people into danger. “This change will put workers on the street who could otherwise afford rent, it will starve the children of sex workers who could otherwise afford to feed them, and it will force workers currently working remotely online into riskier street-based sex work,” said Mary Moody, an online sex worker and co-chair of the Adult Industry Laborers and Artists Association.

...

For people who made a living off studio porn previously, the move to OnlyFans has meant significantly more control over safety, partner choice and representation – particularly important for performers of color and trans people,” she said. “This decision will move control and profit back into producers’ hands.”

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

And here's a followup from Fortune:

OnlyFans tries to win back its spurned lovers BY ROBERT HACKETT  AND DECLAN HARTY August 25

"After an outpouring of shock, dismay, and betrayal from its once and former fans, OnlyFans said Wednesday it was reversing a week-old decision to ban sexually explicit content on its service. "

Thursday, August 26, 2021

The Limits of the Markets - Commodification of Nature and Body, reviewed in OEconomia

 The journal OEconomia has a review of the book 

Élodie Bertrand, Marie-Xavière Catto and Alicia-Dorothy Mornington (eds), Les limites du marché - La marchandisation de la nature et du corps / The Limits of the Markets - Commodification of Nature and Body, Paris: Mare & Martin, 2020, 320 pages

(From the publisher's page:

"How to limit the market, when its progressive ex tension is now gaining fields which until recently escaped it, such as the body and nature? This question is at the heart of Commodification Studies, studies that focus on the ethical, moral or social problems posed by certain particular markets (surrogacy, organs, environmental services, etc.). Can we escape certain forms of commodification when technical advances have allowed new “objects” to circulate?")


Here is the (16 page) review in OEconomia:

Christian Bessy, “Addressing Moral Concerns Raised by the Market”, Œconomia [Online], 11-2 | 2021, oeconomia/10975 ; DOI: https://doi.org/10.4000/oeconomia.10975

It opens as follows:

"This collective work, which brings together some fifteen contributions, is the result of study days whose main purpose was to debate the commodification of the body and of nature, by crossing disciplinary (philosophy, law, economics) and cultural (Anglo-Saxon and continental) perspectives. Its main interest is to propose a sort of progress report on what is known as commodification studies, which developed in the English-speaking world in the 1980s, largely inspired by the book Contested Commodities by the jurist Margaret Jane Radin (1996). In particular, this stream of research was a reaction to the Law and Economics approach (the Chicago School), which championed the free market. An emblematic example is the article by Elizabeth Landes and Richard Posner (1978), in which they suggested introducing market incentives into the process of adopting new-born babies in order to deal with a baby shortage. The controversies surrounding the emergence of particular markets help to explain the issues involved in regulating these markets and the sometimes alternative solutions that are finally adopted but which may evolve, particularly as a result of globalization.

"Other economists have contributed to this reflection, such as Alvin Roth (2007) with his characterization of so-called “repugnant” or “toxic” markets.

"In France, the commodification studies movement has been developed by lawyers specializing in the law of nature (notably MarieAngèle Hermitte, 2016) and by sociologists who have introduced the notion of “contested markets”, in the sense of markets that provoke strong moral controversies. The book Marchés contestés - Quand le marché rencontre la morale (Contested Markets: When the Market Meets Morality), edited by Philippe Steiner and Marie Trespeuch (2014), is a reference, following on from Viviana Zelizer’s original research (1979) on the development of life insurance. The commodification studies movement must also be linked to philosophical reflections on what is a “good”, reflections explored in depth here by Emmanuel Picavet, with a contribution in which he raises the question of freedom and justice.

"It is precisely the intention of The Limits of the Market to start from the most debateable transactions in order to address more generally the relationship between ethics and economics. In so doing, the book deals with the place of law in these exchanges, or with the different conceptions of the legal human person underlying them."



Wednesday, August 25, 2021

Opioid prescription and curtailment are associated with increased rates of suicide among rural veterans:

 Chronic pain, followed by prescription of opioid pain medicines, is sometimes followed by opioid addiction.  A recent NBER working paper shows that policies to reduce prescriptions are associated with increased rates of suicide, particularly among rural military veterans.  Presumably some of these are related to addiction, and some are related to pain.

The Opioid Safety Initiative and Veteran Suicides by Joshua C. Tibbitts & Benjamin W. Cowan WORKING PAPER 29139, DOI 10.3386/w29139,  August 2021

"We investigate the relationship between opioid diverting policy and suicides among the veteran population. The opioid epidemic of the past two decades has had devastating health consequences among U.S. veterans and military personnel. In 2013, the Veterans Health Administration (VA) implemented the Opioid Safety Initiative (OSI) with the goal of discouraging prescription opioid dependence among VA patients. Between 2012 and 2017, prescription opioids dispensed by the VA fell 41% (VA, 2018). Because this involved the aggressive curtailing of opioid prescriptions for many VA patients, OSI may have had a detrimental effect on veterans’ mental health leading to suicide in extreme cases. In addition, because rural veterans have much higher rates of VA enrollment, more prescription opioid use and abuse, and lower rates of substance abuse and mental health treatment utilization, we expect any effect of OSI on veteran suicides to be concentrated in rural areas. We find that OSI raised the veteran suicide rate relative to the non-veteran (“civilian”) rate with rural veterans suffering the lion’s share of the increase. We estimate that OSI raised the rural veteran suicide rate by a little over one-third between 2013 and 2018."

Tuesday, August 24, 2021

Unraveling for consulting: recruiting for next summer has begun.

 Here's a (gated) story from Business Insider, saying that big consulting firms have already started recruiting college juniors for Summer 2022 internships.  The article points out that investment banks are already recruiting very early too, and suggest that this is the consulting firms' reaction.

Deadlines for summer 2022 internships at Big 3 giants like McKinsey, Bain, and BCG are already whizzing by. Here's why they've kicked off recruiting earlier than ever. Reed Alexander and Samantha Stokes 

 

 

Monday, August 23, 2021

A podcast about (and for) kidney donors

Here's a new podcast, that now has several episodes.


"Shining a light on the guts and the glory of living organ donation"

Sunday, August 22, 2021

Disruptive marketplaces in HBR, by Clifford Maxwell and Scott Kominers

 Here's a Harvard Business Review article on markets that create new kinds of transactions.

What Makes an Online Marketplace Disruptive?  by Clifford Maxwell and Scott Duke Kominers

"Summary.   Platforms like Airbnb, eBay, and Angie’s List have changed how markets work. But while many are innovative and make life easier for consumers, which are truly disruptive? Hewing to Clay Christensen’s theory of disruption, platforms — which operate as online marketplaces — are disruptive when they create new consumers, producers, or both, functionally creating new transactions (and new kinds of transactions) that weren’t possible before. Specifically, there are four novel transaction types that can unlock disruptive potential: smaller supply units, bundles, new suppliers, and trust wrappers.

...

"For a marketplace to be disruptive, it must identify either new supply, new demand, or both — targeting individuals or businesses who were unable to profitably produce or consume goods and services in incumbent channels. And the most powerful disruptive marketplaces are often those that simultaneously connect nonconsumers with nonproducers."

A link in the article points to "what venture capital firm Andreessen Horowitz identified as the top 100 marketplace startups in 2020."

That report notes that "The biggest marketplace companies are big—really big. The top 4 companies (Airbnb, Doordash, Instacart, and Postmates) account for 76 percent of the list’s total observed GMV, even though there are 96 other marketplace companies on the list. Interestingly, three of the four are ways to get food delivered to your home. Similarly, almost all the companies on the list harness technology to interact with the offline world—using mobile apps to make food, healthcare, childcare, and fitness more convenient and accessible. "

Saturday, August 21, 2021

Introduction to NLDAC (the National Living Donor Assistance Center)

 I'm on the advisory board of the National Living Donor Assistance Center, which has recently gotten increased resources and mandate to financially support means-tested living kidney donors who have out of pocket expenses for travel, child care, and lost wages.  Nondirected donors are now also eligible for support. The idea is to remove financial disincentives for donation, and NLDAC aims to backstop other efforts, as a federally funded payer of last resort.

They are trying to spread the word, and have prepared a one minute video: Introduction to NLDAC

"Learn about support for people considering living organ donation. NLDAC helps eligible donors with travel, lost wages, and dependent care costs. Visit our website to learn more. Your transplant center can help you apply."

Friday, August 20, 2021

Preference Signaling and Worker-Firm Matching: Evidence from Interview Auctions, by Laschever and Weinstein

 Here's a recent working paper from the IZA Institute of Labor Economics concerned with the importance of signals of interest in labor market matching:

Preference Signaling and Worker-Firm Matching: Evidence from Interview Auctions, by Ron A. Laschever and Russell Weinstein,  IZA DP No. 14622

Abstract: "We study whether there are improvements in worker-firm matching when employers and applicants can credibly signal their interest in a match. Using a detailed résumé dataset of more than 400 applicants from one university over five years, we analyze a matching process in which firms fill some of their interview slots by invitation and the remainder are filled by an auction. Consistent with the predictions of a signaling model, we find the auction is valuable for less desirable firms trying to hire high desirability applicants. Second, we find evidence that is consistent with the auction benefiting overlooked applicants. Candidates who are less likely to be invited for an interview (e.g., non-U.S. citizens) are hired after having the opportunity to interview through the auction. Among hires, these candidates are more represented among auction winners than invited interviewees, and this difference is more pronounced at more desirable firms. Finally, counterfactual analysis shows the auction increases the number and quality of hires for less desirable firms, and total hires in the market

...

"Auctions for interview slots may address two important frictions in the matching process: uncertainty over applicant quality, and uncertainty over the likelihood that an applicant accepts an offer. Even if employers can successfully identify desirable applicants, there remains the challenge of identifying which candidates are truly interested in the job and would accept an o↵er with high probability. In recent years the cost of job applications has fallen as more postings and applications are online. This
further raises the potential that applicants will have a low likelihood of accepting an offer.
...
"Though not common, there are a few markets in which all applicants have an equal opportunity to credibly signal their preferences for an employer. One example is the American Economic Association (AEA) job signaling mechanism, which allows candidates to send a signal of interest to two departments. Importantly, there is no requirement that employers interview the applicants sending the signal. In contrast, in our setting an employer is compelled to meet with some signaling job seekers.

"A second example, and the focus of this paper, is the auction system used in the market for professional master’s degree students, most commonly MBA students, at many top-ranked programs. These programs allow employers to choose some percentage of the applicants they interview, but require the remainder of the interview slots are allocated through an auction. Typically, firms first invite applicants for interviews, before applicants have had the opportunity to signal. Next, there is an auction for the remaining interview slots, and thus auction participants are students who were not invited for an interview by the firm. Each student is provided with an equal allotment of “bid points,” and the auction winners are guaranteed interviews
with the firm."

Thursday, August 19, 2021

Radical content on YouTube, in PNAS

 Here's a paper in PNAS which finds that YouTube viewing of politically radical content reflects viewers' other web behavior, rather than being driven by the YouTube recommender system.

Examining the consumption of radical content on YouTube by Homa Hosseinmardi,  Amir Ghasemian,   Aaron Clauset,   Markus Mobius,   eDavid M. Rothschild, and   Duncan J. Watts. 

PNAS August 10, 2021 118 (32) e2101967118; https://doi.org/10.1073/pnas.2101967118

Abstract: Although it is under-studied relative to other social media platforms, YouTube is arguably the largest and most engaging online media consumption platform in the world. Recently, YouTube’s scale has fueled concerns that YouTube users are being radicalized via a combination of biased recommendations and ostensibly apolitical “anti-woke” channels, both of which have been claimed to direct attention to radical political content. Here we test this hypothesis using a representative panel of more than 300,000 Americans and their individual-level browsing behavior, on and off YouTube, from January 2016 through December 2019. Using a labeled set of political news channels, we find that news consumption on YouTube is dominated by mainstream and largely centrist sources. Consumers of far-right content, while more engaged than average, represent a small and stable percentage of news consumers. However, consumption of “anti-woke” content, defined in terms of its opposition to progressive intellectual and political agendas, grew steadily in popularity and is correlated with consumption of far-right content off-platform. We find no evidence that engagement with far-right content is caused by YouTube recommendations systematically, nor do we find clear evidence that anti-woke channels serve as a gateway to the far right. Rather, consumption of political content on YouTube appears to reflect individual preferences that extend across the web as a whole.


"Our data are drawn from Nielsen’s nationally representative desktop web panel, spanning January 2016 through December 2019 (SI Appendix, section B), which records individuals’ visits to specific URLs. We use the subset of N = 309,813 panelists who have at least one recorded YouTube pageview. Parsing the recorded URLs, we found a total of 21,385,962 watched-video pageviews (Table 1). We quantify the user’s attention by the duration of in-focus visit to each video in total minutes (32)."


Wednesday, August 18, 2021

1st ACM Conference on Equity and Access in Algorithms, Mechanisms, and Optimization (EAAMO'21)

 Irene Lo writes:

As many of you may know, I've been part of launching a new ACM conference series and publication venue: the 1st ACM Conference on Equity and Access in Algorithms, Mechanisms, and Optimization (EAAMO'21). Registration is now live, and I'd be delighted to see many of you there! See below for more details.

***

We are thrilled to announce that the registration for EAAMO ‘21 is now live! Please register for regular admission on Eventbrite by September 10, 2021.

Conference registration is $20 for ACM members, $15 for students, and $35 for non-ACM members. We also provide financial assistance and data grants in order to waive registration fees and provide data plans to facilitate virtual attendance. Please apply here before September 10, 2021.

A main goal of the conference is to bridge research and practice. Please nominate practitioners working with underserved and disadvantaged communities to join us at the conference (you can also nominate yourself if you are a practitioner). Invited practitioners will be included in facilitated discussions with researchers. 

For more information, please see below or visit our website and contact us at gc@eaamo.org with any questions.

***

 The inaugural Conference on Equity and Access in Algorithms, Mechanisms, and Optimization (EAAMO ‘21) will take place on October 5-9, 2021, virtually, on Zoom and Gather.town. EAAMO ‘21 will be sponsored by ACM SIGAI and SIGecom

 

The goal of this event is to highlight work where techniques from algorithms, optimization, and mechanism design, along with insights from the social sciences and humanistic studies, can improve access to opportunity for historically underserved and disadvantaged communities. 

 

The conference aims to foster a multi-disciplinary community, facilitating interactions between academia, industry, and the public and voluntary sectors. The program will feature keynote presentations from researchers and practitioners as well as contributed presentations in the research and policy & practice tracks. 

We are excited to host a series of keynote speakers from a variety of fields: Solomon Assefa (IBM Research), Dirk Bergemann (Yale University), Ellora Derenoncourt (University of California, Berkeley), Ashish Goel (Stanford University), Mary Gray (Microsoft Research), Krishna Gummadi (Max Planck Institute for Software Systems), Avinatan Hassidim (Bar Ilan University), Radhika Khosla (University of Oxford), Sylvia Ortega Salazar (National College of Vocational and Professional Training), and Trooper Sanders (Benefits Data Trust).

 

ACM EAAMO is part of the Mechanism Design for Social Good (MD4SG) initiative, and builds on the MD4SG technical workshop series and tutorials at conferences including ACM EC, ACM COMPASS, ACM FAccT, and WINE.