Friday, July 10, 2020

Blockchain economics, by Catalini and Gans; and Halaburda, Haeringer, Gans and Gandal


Some Simple Economics of the Blockchain
By Christian Catalini and Joshua S. Gans
Communications of the ACM, July 2020, Vol. 63 No. 7, Pages 80-90

"we rely on economic theory to explain how two key costs affected by blockchain technology—the cost of verification of state, and the cost of networking—change the types of transactions that can be supported in the economy. These costs have implications for the design and efficiency of digital platforms, and open opportunities for new approaches to data ownership, privacy, and licensing; monetization of digital content; auctions and reputation systems."
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The Microeconomics of Cryptocurrencies
Hanna Halaburda, Guillaume Haeringer, Joshua S. Gans, Neil Gandal
NBER Working Paper No. 27477  July 2020

Abstract: Since its launch in 2009 much has been written about Bitcoin, cryptocurrencies and blockchains. While the discussions initially took place mostly on blogs and other popular media, we now are witnessing the emergence of a growing body of rigorous academic research on these topics. By the nature of the phenomenon analyzed, this research spans many academic disciplines including macroeconomics, law and economics and computer science. This survey focuses on the microeconomics of cryptocurrencies themselves. What drives their supply, demand, trading price and competition amongst them. This literature has been emerging over the past decade and the purpose of this paper is to summarize its main findings so as to establish a base upon which future research can be conducted.

Thursday, July 9, 2020

Safe injection sites: surreptitious harm reduction, in the NEJM

When healthcare interventions must be conducted secretly, it's likely that something is very wrong with the law.

A letter in the New England Journal of Medicine brings us up to date on safe injection sites, to combat deaths from drug overdoses.

by Alex H. Kral, Ph.D., Barrot H. Lambdin, Ph.D., Lynn D. Wenger, M.S.W., M.P.H., and 
Pete J. Davidson, Ph.D.    July 8, 2020

"Nearly 70,000 people in the United States die each year from a drug overdose.1 Opioid-involved overdose deaths may be preventable by the timely administration of naloxone. Eleven countries have responded to health concerns regarding people who use drugs by opening sanctioned safe consumption sites; however, no such sites exist yet in the United States. Safe consumption sites provide a space for people to bring preobtained drugs and use them with sterile supplies under clean conditions and with safe disposal of used drug equipment. These sites provide monitoring by staff equipped and trained in the use of naloxone to reverse overdose. Most sanctioned sites can also provide related services, including voluntary screening for infectious diseases, peer counseling, wound care, and referral to other social and medical services, such as substance use treatment. 
...
"In September 2014, in response to a local opioid overdose crisis, an organization in an undisclosed U.S. city opened an unsanctioned safe consumption site


"Although this evaluation was limited to one city and one site that is unsanctioned, and therefore the findings cannot be generalized, our results suggest that implementing sanctioned safe consumption sites in the United States could reduce mortality from opioid-involved overdose. Sanctioning sites could allow persons to link to other medical and social services, including treatment for substance use, and facilitate rigorous evaluation of their implementation and effect on reducing problems such as public injection of drugs and improperly discarded syringes."

Wednesday, July 8, 2020

Will curtailing early hiring/unraveling help diversity?

If you run a company that hires very early, you likely hire from familiar places.  If talented recruits from more diverse backgrounds are harder to identify very early, you might want to slow things down a bit.  Here's a WSJ story, about what might signal a change in the famously unraveled market for young analysts in private equity:


Blackstone to Bypass Scramble for Investment-Bank Talent in Bid to Diversify Hiring
On-campus recruiting will be expanded to 44 schools from nine in 2015
By Miriam Gottfried, June 24, 2020

"Blackstone Group Inc., ...one of the most coveted employers on Wall Street, is throwing out a key section of its recruiting playbook in a bid to improve its hiring process and increase diversity.

"The investing giant and its private-equity peers have long engaged in a yearly race to pluck junior investment bankers already trained in spreadsheet and PowerPoint wizardry from firms such as Goldman Sachs Group Inc. and Morgan Stanley. The prize for those lucky enough to make the jump: entry-level jobs that can pay as much as $300,000 a year at some firms.

"Now Blackstone officials say the firm plans to sit out that contest in favor of on-campus recruiting, already its main source of talent and one that it is expanding to bring in more candidates directly from schools, including historically black colleges and universities and women’s colleges. Blackstone, which has been working for years to extend its campus reach, says it will directly recruit from 44 schools this academic year. That is up from just nine in 2015.
...
"Blackstone, the largest buyout firm with $538 billion of assets, received nearly 15,000 applications for just 90 full-time analyst roles that started last year. It has two main sources of new junior talent: campuses and investment banks, which have their own hotly competitive entry-level hiring operations.

In the case of the latter, recruitment used to happen during the summer after applicants’ first year on the job, but it has steadily crept forward as private-equity firms jump the starting gun in hopes of securing the best candidates. In 2019, recruiting took place in September, just a couple months after candidates began working at banks—for roles that wouldn’t start until summer 2021."

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Here's an earlier related post (from long ago, before Covid-19 and George Floyd...):

Monday, December 9, 2019

Tuesday, July 7, 2020

Should deceased donors be allowed to donate sperm?

Deceased donor sperm donation is the subject of an article earlier this year, in light of the shortage of donated sperm in the UK:

Hodson N, Parker J. "The ethical case for non-directed postmortem sperm donation,"
Journal of Medical Ethics 2020;46:489-492.

Abstract: In this article we outline and defend the concept of voluntary non-directed postmortem sperm donation. This approach offers a potential means of increasing the quantity and heterogeneity of donor sperm. This is pertinent given the present context of a donor sperm shortage in the UK. Beyond making the case that it is technically feasible for dead men to donate their sperm for use in reproduction, we argue that this is ethically permissible. The inability to access donor sperm and the suffering this causes, we argue, justifies allowing access to sperm donated after death. Moreover, it is known that individuals and couples have desires for certain sperm donor characteristics which may not be fulfilled when numbers of sperm donors are low. Enacting these preferences contributes significantly to the well-being of intended parents, so we argue that this provides a pro tanto reason for respecting them. Finally, we explore the benefits and possible disadvantages of such a system for the various parties affected.

"The United Kingdom (UK) has a shortage of donor sperm. In 2016 there were 2273 donor insemination treatment cycles; 42% of the women registering had a male partner, 41% had a female partner and 17% were single.1 The average number of newly registered sperm donors per year between 2011 and 2013 was 586, an increase from 2004 where there were 237 donors.2 Yet this increase includes donations for specific use by a known individual to create one offspring. In 2016 the Human Fertilisation and Embryology Authority (HFEA) reported 4306 in vitro fertilisation (IVF) treatment cycles with ‘own eggs and donor sperm’ and 924 treatment cycles with ‘donor egg and donor sperm’.1 Clearly there is high demand for donor sperm and HFEA reports demonstrate this is increasing.1

"Commercial imports have been the mainstay of UK efforts to keep up with increasing demand for donor sperm.1 The Department of Health and Social Care estimates that 4000 samples were imported from the USA and 3000 from Denmark in addition to samples from other European Union (EU) countries.3 The HFEA highlights that imports are used to plug the gap because "the cost, time and resources required to recruit donors themselves is too high when there are specialist sperm banks who can carry out an efficient and reliable service".4 The Department of Health and Social Care has raised concerns that the UK's departure from the EU may worsen this state of affairs.3
...
"There are barriers to donating sperm in life that may prevent some men acting on their desire to help others or see their genes continue into future generations through donation. Posthumous sperm donation avoids most of these problems, allowing men to access the positives of sperm donation without the drawbacks. Living kidney donation provides an informative comparison between the motivations to donate in life versus after death. It is difficult to overestimate the value of donated kidneys to those individuals on the transplant list. Many people feel the pull of altruism and have a desire to help those who need a kidney transplant. Yet the potential costs of donating during life mean that individuals would rather donate after death when those costs are eliminated.16 Gamete donation after death parallels kidney donation by offering the same benefits as donation in life with fewer drawbacks, thereby both incentivising men to donate and providing greater opportunity to fulfil some of their reproductive and altruistic desires. This makes voluntary postmortem sperm donation an attractive addition to living donation.
...
"Given the potential impact of postmortem sperm donation on the family, policy decisions could be used to soften the implications of postmortem sperm donation for the family. For our purposes, the important point is that considerations of the family, including a romantic partner surviving the deceased man, do not justify a blanket ban on the use of sperm collected after death, especially if the donor has specified a desire to donate.
...
"The UK consensus is that gametes ought not to be bought although donor expenses should be covered.37 We do not take a view on this generally, but note the dissonance generated when sperm from countries such as Denmark where ‘vendors’ have been paid is used in the UK.38 In so far as society benefits from a coherent bioethical policy reflecting its shared values, using dead donors rather than donors who were paid in other countries to bolster supplies might provide a more coherent policy.

Monday, July 6, 2020

Netherlands now has opt out deceased donor registration

The Netherlands Times has the story:

NEW DONOR REGISTRY OPT-OUT RULE TAKES EFFECT TODAY
By Janene Pieters on Wednesday, 1 July 2020

"The Netherlands' new organ donation law takes effect today. From now on Dutch adults who haven't told the Donor Register their wishes for their organs after death will automatically be registered as "no objection to organ donation", instead of automatically being registered as a non-donor. This means their organs can go to a patient after their death, though their next of kin will first be consulted.
"According to the government, almost 7 million Netherlands residents have not registered their wishes with the Donor Register yet. They will be sent a letter, prompting them to do so. Residents of Noord-Holland will be the first to receive this letter in September and October. A second letter will be sent six weeks later. If no response is received after the two letters, the person will be registered as "no objection to organ donation".
"Of those who have registered their wishes with the Donor Register, 53 percent are registered as organ donors. About 36 percent are non-donors, and 11 percent decided to leave this decision up to their families. "
**************
In the U.S., almost 50% of drivers are registered donors, close to the Netherlands rate. But it looks like the 36 percent "non donors" have given a definite "no" to donation. It will be interesting to see how the deceased donor transplantation rate evolves in the Netherlands.

Sunday, July 5, 2020

Czech-Austrian and Swedish-Danish kidney exchange

Overcoming borders makes the market thicker.

Here's a paper on kidney exchange across between Austria and the Czech Republic from the most recent edition of Transplant International:

Crossing borders to facilitate live donor kidneytransplantation: the Czech-Austrian kidney paired donation program – a retrospective study 
Ondrej Viklicky1 , Sebastian Krivanec2 , Hana Vavrinova1 , Gabriela Berlakovich3 , Tomas Marada4 , Janka Slatinska1 , Tereza Neradova4 , Renata Zamecnikova4 , Andreas Salat3 , Michael Hofmann3 , Gottfried Fischer5 , Antonij Slavcev6 , Pavel Chromy4 , Rainer Oberbauer2 , Tomas Pantoflicek4 , Sabine Wenda5 , Elisabeth Lehner2 , Ingrid Fae5 , Paolo Ferrari7,8,9 , Jiri Fronek4 & Georg A. Bohmig

SUMMARY Kidney paired donation (KPD) is a valuable tool to overcome immunological barriers in living donor transplantation. While small national registries encounter difficulties in finding compatible matches, multi-national KPD may be a useful strategy to facilitate transplantation. The Czech (Prague) and Austrian (Vienna) KPD programs, both initiated in 2011, were merged in 2015. A bi-national algorithm allowed for ABO- and low-level HLA antibody-incompatible exchanges, including the option of altruistic donor initiated domino chains. Between 2011 and 2019, 222 recipients and their incompatible donors were registered. Of those, 95.7% (Prague) and 67.9% (Vienna) entered into KPD registries, and 81 patients received a transplant (95% 3-year graft survival). Inclusion of ABO-incompatible pairs in the Czech program contributed to higher KPD transplant rates (42.6% vs. 23.6% in Austria). After 2015 (11 bi-national match runs), the median pool size increased to 18 pairs, yielding 33 transplants (8 via cross-border exchanges). While matching rates doubled in Austria (from 9.1% to 18.8%), rates decreased in the Czech program, partly due to implementation of more stringent HLA antibody thresholds. Our results demonstrate the feasibility of merging small national KPD programs to increase pool sizes and may encourage the implementation of multi-national registries to expand the full potential of KPD.
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And here's a paper on kidney exchange between Sweden and Denmark:

De första njurbytena mellan två skandinaviska länder är gjorda
The first kidney exchanges between two Scandinavian countries are made
Scandinavian expansion of the renal exchange program STEP
Tommy Andersson, Professor, Lars Wennberg , Per Lindnér, Ilse Duus Weinreich, Karin Skov, Claus Bistrup

SUMMARY: The first kidney exchanges between two Scandinavian countries have been performed
This article describes the Scandinavian expansion of the previously described kidney exchange program STEP, and the first two exchanges performed between two Scandinavian countries late in 2019. All surgical procedures were performed simultaneously and / or coordinated at different hospitals in Scandinavia and the kidney grafts were transported between the participating units. Four weeks after surgery, all recipients had a good and stable kidney function and all donors had recovered.
*********

see earlier post:

Wednesday, December 25, 2019

Saturday, July 4, 2020

Stanford GSB highlights Akbarpour and van Dijk on the virtues of strategy-proof school choice


Here's an article on the Stanford GSB website, describing a paper by Mohammad Akbarpour and Winnie van Dijk:

How School Choice Systems Create Unfair Advantages
Lotteries for public school admissions unintentionally favor students who have the option to attend private institutions, a new study shows.
June 26, 2020|by Maggie Overfelt

And here's the paper that the article highlights:
School Choice with Unequal Outside Options
September 2018 Working Paper No. 3764
Students with identical valuations for public schools but unequal outside options have different opportunity costs of revealing their preferences. Consequently, manipulable mechanisms need not resolve conflicting preferences in a Pareto-improving manner. We show that when they do not, welfare improvements for students with outside options come at the expense of students without outside options. This result strengthens the argument that strategyproof mechanisms “level the playing field.” Our model predicts that students without outside options are more likely to strategize, consistent with recent findings in empirical studies of education markets.

Friday, July 3, 2020

Job market technology is diffusing slowly through the armed forces

Here's a story from the Army Times, about trying to incorporate enlisted soldiers' preferences into their job assignments. (I hope to have something more to say about this in the future.)

Enlisted job marketplace launches this summer for select soldiers
 by Kyle Rempfer

"Armor, intelligence and some quartermaster troops will test a new assignment market system that launches this summer and is scheduled to go service-wide in January 2021, according to an Army news service release.
The Assignment Satisfaction Key-Enlisted Marketplace pilot program will launch in June, but was already tested by a smaller group of armor branch noncommissioned officers last year.
"The enlisted program matches up roughly with a similar officer marketplace already in use. The Army’s talent management initiatives began with the officer corps, because the population is much smaller and easier to run trials on than the enlisted force, according to Sgt. Maj. Wardell Jefferson, the Army G-1’s senior enlisted soldier.
...
"The pilot program could provide enlisted troops more choice in their careers than the current assignment system, which forces troops to choose six basing options — three in the United States and three overseas, Jefferson explained during a Facebook Town Hall on Monday.
The new system is expected to allow soldiers to rank order more assignment preferences. Army leaders have said that the marketplace will stabilize enlisted soldiers’ careers by weighing their preferences more in the assignment process and ensuring good soldiers are retained rather than lost to the civilian sector..

Thursday, July 2, 2020

John Harsayni, on Hungarian coinage (and a memorable conversation)

The title of this blogpost is ambiguous, but the picture should disambiguate it. (As far as I know, the late great game theorist, who initiated the literature on Bayesian games of incomplete information, never wrote about coinage):



Here's the story:

Hungarian Mint Commemorates Nobel Prize Winner János Harsányi
By CoinWeek -June 25, 2020

"János (or John Charles) Harsányi, the 1994 Nobel Memorial Prize laureate in Economic Sciences, was born in Budapest on May 29, 1920. His primary field of research was game theory, for which he was awarded the Nobel Memorial Prize with John Forbes Nash and Reinhard Selten in Economic Sciences “For his ground-breaking work in the area of non-cooperative game theory and equilibrium analysis.” In the field of game theory, they were the first scientists to receive the Nobel Prize in Economics.
...
"The Hungarian Mint has issued a silver collector coin of 10,000 forints and a copper-nickel version of 2,000 forints on the 100th anniversary of the distinguished University of California at Berkeley researcher’s birth.
...
"The silver coin, with a face value of 10,000 forint is struck in .925 fine silver and weighs 31.46 grams. It costs $67.50. The non-ferrous metal 2,000 forint is produced from an alloy of copper (75%) and nickel (25%) and weighs 30.8 grams. It is priced at $19.95. The mintage limit of both the silver collector coin in proof finish and that of the non-ferrous version in BU finish is 5,000 pieces of each."
************

I don't need a coin to remind me of John, but reading about his monetization brought back a particularly memorable conversation.

In the summer of 1975, after completing my first year as an assistant professor at the University of Illinois, I drove back to California to spend the summer visiting Harsanyi at Berkeley. I had perhaps imagined many long conversations, but the way he made space for me was to give me his office, while he worked from home. So our conversations were not so frequent, and were somewhat formal: he called me Professor Roth, and I of course called him Professor Harsanyi.

On at least one occasion I drove him down to Stanford when there was a seminar we both wanted to attend. The conversation I recall most vividly came on the return trip from one of these, when we gave a lift up to Berkeley to Bob Aumann, who had purchased a used car there and needed to pick it up.  We all rode in my fairly small 1966 Ford Mustang (purchased used in 1971 when I began graduate school.)  I drove, Harsanyi sat in the front passenger seat, and Bob sat behind him

We had a lively conversation the whole way. What I remember about it were the forms of address. Bob and John, and Bob and I, were naturally on a first name basis. But, throughout the drive, Harsanyi called me Professor Roth, and I called him Professor Harsanyi.  I hope I didn't show that I thought it was hilarious, but it is possible that I addressed my passengers by name more often than strictly necessary. And so it went, Bob and John, Al and Bob, Professor Harsanyi and Professor Roth.

We stopped at the house Bob was going to, and as soon as the car door closed behind him, Professor Harsanyi turned to me and said "Professor Roth, perhaps it would be best if we went to a first name basis." 

And so we did.

Wednesday, July 1, 2020

Field experiments as/and market design in the July AER


(2) Field Experiments and the Practice of Economics
Abhijit Vinayak Banerjee
Full-Text Access | Supplementary Materials

"When, some twenty-five years ago, I first started doing RCTs, the most common reaction was one of puzzled tolerance. Colleagues and friends seemed to admire the effort involved and could see that RCTs had the advantage of avoiding the then common wrangling about what is causal and what is not. But in the end they were skeptical that it was worth it. In part they were concerned for me: I had a successful career doing economics (in particular economic theory) the way it was done then. Why go down this particular rabbit-hole? But more importantly, as the more candid among them put it, “are RCTs economics?”
...
At the risk of some caricature, there are really four closely related questions:
(i) Economics aspires to generate generalizable knowledge. RCTs focus on estimating the impacts of specific interventions. Aren’t these fundamentally different ways of approaching the world?
(ii) Economics tackles big questions. RCTs by their very nature provide narrow and specific answers. How do we square that gap?
(iii) Economics is about cumulatively building a theory, by building on the existing theories and making use of any new pieces of evidence to enrich the theory. Aren’t RCTs piecemeal: one insight here, one insight there?
(iv) Why are economists needed to run RCTs? Wouldn’t it be better to have  competent applied statisticians or the World Bank run them?
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(3) Field Experiments and the Practice of Policy
Esther Duflo
Full-Text Access | Supplementary Materials

"I was not destined to be an economist. As the daughter of a mathematician, I was quite sure I would become an academic. My heroes were Gauss, the mathematical genius, and Emmanuel Le Roy Ladurie, the quantitative historian who found  peasants interesting, rather than kings. But as the daughter of a physician who spent time trying to be helpful in countries where children were victims of war, I also aspired to be a change maker. I felt that the only repayment for the incredible luck I had in my life was to do whatever I could to try to improve the lives of the many people who were not that lucky. My heroes were Mother Teresa and Albert Schweitzer. Of course, I had no idea how to combine those two aspirations, but I hoped that one day I would find a way.

"Until quite late in my college career, economics did not occur to me as a plausible path for accomplishing these goals."
**********
(4) Experimentation, Innovation, and Economics
Michael Kremer
"The experimental method not only helps identify causal relationships, but also provides economists with a rich sense of context, focuses research on specific practical questions, stimulates collaboration with practitioners and specialists from other fields, and allows for rapid iteration. In this lecture, I present a series of examples illustrating how together these features make the experimental approach a powerful tool for advancing scientific understanding, informing policy, and promoting innovation. I then discuss how institutions can be designed to accelerate innovation and direct it toward the world's most pressing needs."
(11) Incentivized Kidney Exchange
Tayfun Sönmez, M. Utku Ünver and M. Bumin Yenmez
Over the last 15 years, kidney exchange has become a mainstream paradigm to increase transplants. However, compatible pairs do not participate, and full benefits from exchange can be realized only if they do. We propose incentivizing compatible pairs to participate in exchange by insuring their patients against future renal failure via increased priority in deceased-donor queue. We analyze equity and welfare benefits of this scheme through a new dynamic continuum model. We calibrate the model with US data and quantify substantial gains from adopting incentivized exchange, both in terms of access to living-donor transplants and reduced competition for deceased-donor transplants.

Tuesday, June 30, 2020

The fall and rise of food supplies in Covid-19 India, by Matt Lowe and Ben Roth

Pandemic lock downs gave food supply a shock in Indian markets, but they have recovered.

COVID Lockdown: How India's Food Supply Chain First Tightened and then Recovered
"Food supply shortages, if any, are driven by state level policy making, rather than consumers’ and suppliers’ fears of contracting COVID-19."
by Matt Lowe and Ben Roth


"In mid-April, the supply of fruits and vegetables at Azadpur, Asia’s largest fruit and vegetable market, had fallen about 50% since the start of India’s nationwide lockdown.
Two months later, updated nationwide data shows that India’s food supply chain appears to have recovered, operating at levels comparable to the same time last year. The story of the recovery is best told with four food facts, the sum of which tell its own tale of governance during the COVID-19 pandemic times.
Food fact 1: Food volumes took a huge hit post-lockdown but have steadily recovered.
...
Food fact 2: Food prices increased post-lockdown but have steadily fallen.
...
Food Fact 3: The early disruption to the food supply chain was highly correlated with the incidence of COVID-19 at the state level, but all states appear to be recovering.
...
Food Fact 4: Within states, there was no relationship between the incidence of COVID-19 and the health of the food supply chain, even in phase 1.
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Earlier post: 

Thursday, April 16, 2020

Monday, June 29, 2020

New seminar series on Marketplace Algorithms and Design.

Yash Kanoria writes to alert me to their new seminar series:


Gagan Goel, Daniela Saban, and Yash Kanoria (with help from Judy Gan) are organizing a seminar on Marketplace Algorithms and Design.

We will start with an "Ask me anything" session with Preston McAfee on Tuesday June 30th, 11am-12pm PT. Thereafter, on Thursdays, 11am - 12pm PT we have:
· July 9: Navdeep Sahni, "Search Advertising and Information Discovery: Are Consumers Averse to Sponsored Messages?"
· July 23: Ramesh Johari, "Experimental Design in Two-Sided Platforms: An Analysis of Bias"
· July 30: Sera Linardi, "Worker-Firm Relational Contracts at the Time of Shutdowns: Experimental Evidence"
Zoom info: https://zoom.us/j/97125802655  password: please request it by filling this form
Simultaneous Youtube live stream channel
Time: 11 am to noon Pacific Time

Sunday, June 28, 2020

Course allocation with minimum quotas, by Bichler, Hammerl, Waldherr, and Morrill

Here's a course allocation problem:, "Our specific task was to assign students to classes in the computer science and information systems department at the Technical University of Munich, a large European university. This department is currently the largest department at the university with more than 6,000 students."

How to Assign Scarce Resources Without Money:  Designing Information Systems that are Efficient, Truthful, and (Pretty) Fair
Martin Bichler, Alexander Hammerl, Stefan Waldherr,  Thayer Morrill
INFORMATION SYSTEMS RESEARCH, forthcoming.


"Matching with preferences has great potential to coordinate the efficient allocation of scarce resources in organizations when monetary transfers are not available, and thus can provide a powerful design principle for information systems. Unfortunately, it is well-known that it is impossible to combine all three properties of truthfulness, efficiency, and fairness (i.e. envy-freeness) in matching with preferences. Established mechanisms are either efficient or envy-free, and the efficiency loss in envy-free mechanisms is substantial. We focus on a widespread representative of a matching problem: course assignment where students have preferences for courses and organizers have priorities over students. An important feature in course assignment is that a course has both a maximum capacity and a minimum required quota. This is also a requirement in many other matching applications such as school choice, hospital-residents matching, or the assignment of workers to jobs. We introduce RESPCT, a mechanism that respects minimum quotas and is truthful, efficient, and has
low levels of envy. The reduction in envy is significant and is due to two remarkably effective heuristics. We follow a design science approach and provide analytical and experimental results based on field data from a large-scale course assignment application. These results have led to a policy change and the proposed assignment system is now being used to match hundreds of students every semester."

Saturday, June 27, 2020

Strategy proofness in auctions, beyond the frontiers of our most reliable knowledge

A lot of market design goes on beyond the frontiers for which we have robust general theorems. Computational methods are important in these cases (and sometimes the theory follows along eventually).   Here's a recent auction paper on archiv.org that sheds some light on strategy proofness.

Certifying Strategyproof Auction Networks
Michael J. Curry∗ Ping-Yeh Chiang∗ Tom Goldstein and  John P. Dickerson
 
Abstract: Optimal auctions maximize a seller’s expected revenue subject to individual rationality and strategyproofness for the buyers. Myerson’s seminal work in 1981 settled the case of auctioning a single item; however, subsequent decades of work have yielded little progress moving beyond a single item, leaving the design of revenue-maximizing auctions as a central open problem in the field of mechanism design. A recent thread of work in “differentiable economics” has used tools from modern deep learning to instead learn good mechanisms. We focus on the RegretNet architecture, which can represent auctions with arbitrary numbers of items and participants; it is trained to be empirically strategyproof, but the property is never exactly verified leaving potential loopholes for market participants to exploit. We propose ways to explicitly verify strategyproofness under a particular valuation profile using techniques from the neural network verification literature. Doing so requires making several modifications to the RegretNet architecture in order to represent it exactly in an integer program. We train our network and produce certificates in several settings, including settings for which the optimal strategyproof mechanism is not known

Friday, June 26, 2020

Pandemic policies work differently in different places

Here's a recent largely empirical paper by many authors, looking at the actual and counterfactual impact of different pandemic responses in different cities, with the aim (among others) of mapping the employment/mortality frontier of different policies.  They build on GPS and payment data for modeling movement and interpersonal contact, and electronic health records for hospitalization and deaths.  Thus, for example, they find that in Chicago, different policies can make big moves along the employment/mortality frontier (allowing only essential workers to go to work reduces deaths and increases unemployment, both by a lot), while in a more sparsely inhabited city like Sacramento, it's hard to change the mortality rate (but only allowing essential workers still causes lots of unemployment).

Socioeconomic Network Heterogeneity and Pandemic Policy Response
Mohammad Akbarpour, Cody Cook, Aude Marzuoli, Simon Mongey, Abhishek Nagaraj, Matteo Saccarola, Pietro Tebaldi, Shoshana Vasserman, Hanbin Yang
NBER Working Paper No. 27374
Issued in June 2020

Abstract: "We develop a heterogeneous-agents network-based model to analyze alternative policies during a pandemic outbreak, accounting for health and economic trade-offs within the same empirical  framework. We leverage a variety of data sources, including data on individuals' mobility and encounters across metropolitan areas, health records, and measures of the possibility to be productively working from home. This combination of data sources allows us to build a framework in which the severity of a disease outbreak varies across locations and industries, and across individuals who differ by age, occupation, and preexisting health conditions.

"We use this framework to analyze the impact of different social distancing policies in the context of the COVID-19 outbreaks across US metropolitan areas. Our results highlight how outcomes vary across areas in relation to the underlying heterogeneity in population density, social network structures, population health, and employment characteristics. We find that policies by which individuals who can work from home continue to do so, or in which schools and firms alternate schedules across different groups of students and employees, can be effective in limiting the health and healthcare costs of the pandemic outbreak while also reducing employment losses."


Thursday, June 25, 2020

Market designers and ventilator allocation, by Pathak, Sönmez, and Ünver

I recall when a big part of practical market design was explaining to skeptical listeners why they should listen to economists...

June 19, 2020
Improving Ventilator Rationing Through Collaboration With Experts on Resource Allocation
Parag A. Pathak, PhD1; Tayfun Sönmez, PhD2; M. Utku Ünver, PhD2
JAMA Netw Open. 2020;3(6):e2012838. doi:10.1001/jamanetworkopen.2020.12838

"In our study of ventilator rationing guidelines,2 we have not seen task forces include input from experts on market design, a field of economics that studies the allocation of scarce resources. In many settings, price plays a central role in allocation when demand exceeds supply; however, this instrument is often not available in public health emergencies with extreme scarcity. During the last 2 decades, substantial research activity and policy developments have taken place regarding allocation environments where price-based tools are either unavailable or considered repugnant. Two noteworthy examples are the organization of kidney exchanges in the US and the assignment of seats at public schools. Because research in market design incorporates ethical considerations and operationalizes these objectives with an allocation mechanism, scholars in this field can be valuable for transforming various trade-offs between ethical principles into specific allocation procedures."

Wednesday, June 24, 2020

Curbside interviewing / hiring joins curbside pickup in a social-distancing economy


The WSJ has the story:

Job Recruitment Adopts Social Distancing as Coronavirus Alters Practices
Employers rethink how they hire, trying remote onboarding and curbside job fairs to reduce risks
By James T. Areddy, June 22, 2020

"During the parking-lot screening, the couple and other job seekers sat in their cars and provided recruiters, wearing face masks, with basic information for possible callbacks on a range of jobs in light industry and those requiring skilled labor.

"It is an example of how social distancing, needed to stem the coronavirus pandemic, is altering job recruitment."

Tuesday, June 23, 2020

I join the NRMP board of directors

In the 1990's I worked closely with the NRMP on the resident match, and since then I've been following it from a distance.  Now I'll join their Board.  I imagine that during my term there may be an opportunity to look at how the overall system of applications, interviews and matching have co-evolved and adapted to each other.

Here's the NRMP press release:

 NRMP Board Of Directors Welcomes Outstanding Cohort Of New Members
Nobel Prize Recipient Dr. Alvin E. Roth Among Talented Slate of Elected Individuals
Washington, D.C., June 22, 2020 –

At its June meeting, the National Resident Matching Program® (NRMP®) Board of Directors elected five individuals for terms that begin July 1, 2020. The NRMP’s 19-member Board includes medical school deans, institutional officials, clinical program directors, resident/fellow physicians, medical students, and one public member. The appointment of Dr. Alvin E. Roth, the 2012 co-recipient of the Sveriges Riksbank Prize in Economic Sciences in Memory of Alfred Nobel, highlights the quality of the slate of new members.

“The individuals recently elected to the NRMP Board of Directors will bring an impressive mix of professional experiences and fresh perspectives to the governance of the organization,” said NRMP Board Chair Dr. Steven J. Scheinman. “They were selected from a deep pool of accomplished applicants, and we look forward to working with them on an array of initiatives.”

The term for directors is four years, with a maximum of two terms. The term for resident/fellow and student directors is two years. Listed alphabetically, the new members include:

Ricardo J. Boccardo Bello, M.D., General Surgery resident at the University of Massachusetts Medical School. A graduate of the Universidad Central de Venezuela in Caracas, he earned a Master of Public Health from the London School of Hygiene and Tropical Medicine and completed his PGY-1 General Surgery residency and postdoctoral research fellowship in Microsurgery Outcomes at Johns Hopkins University. While at Johns Hopkins, he received the Core Surgery Clerkship Outstanding Junior Resident Teaching Award.

Sydney Miller, Michigan State University College of Osteopathic Medicine student. Elected President of her class, Ms. Miller serves alongside faculty leaders as a member of the Dean’s Executive Board, which deliberates the college’s undergraduate and graduate medical education programs and other strategic initiatives. She earned her undergraduate degree in Human Biology at Michigan State University. Her interests include increasing awareness and appreciation of osteopathic medicine.

Alvin E. Roth, Ph.D., Senior Fellow at the Stanford Institute for Economic Policy Research and a Professor, by courtesy, for the school of Management Science and Engineering. He is also the George Gund Professor of Economics and Business Administration Emeritus at Harvard University. Dr. Roth’s academic expertise is in game theory, experimental economics, and market design, and he was co-recipient of the 2012 Nobel Prize in Economics for work which focused in part on the NRMP’s matching algorithm. He earned a doctoral degree in Operations Research from Stanford University.

Morgan Swanson, M.D./Ph.D. student at the University of Iowa Carver College of Medicine and College of Public Health. She has served with the Association of American Medical Colleges’ Organization of Student Representatives (OSR), most recently as one of 12 students selected to its Administrative Board. Ms. Swanson graduated from Iowa State University and serves as a member of the Editorial Board of the U.S. Centers for Disease Control and Prevention’s Morbidity and Mortality Weekly Report.

Christopher B. Traner, M.D., recent graduate of Neurology residency at Yale-New Haven Hospital and incoming Epilepsy/Neurophysiology fellow at Yale. He received the Yale Neurology Department’s Lewis Levy Award, presented to the PGY-2 resident who best exemplifies clinical excellence. He advised undergraduates as a Kaplan MCAT Advantage Plus Mentor while attending the University of Toledo College of Medicine. As a resident at Yale, Dr. Traner was a member of his program’s Interview Committee.

The newly elected Board members replace those whose terms conclude on June 30: Dr. Zaid Almarzooq, Cardiology fellow, Brigham and Women’s Hospital; Dr. Jessica Fried, chief resident, Diagnostic Radiology, Hospital of the University of Pennsylvania; Dr. Eriny Hanna, 2020 graduate of Vanderbilt University School of Medicine transitioning to an Emergency Medicine residency at Vanderbilt; Father Daniel Morrissey, O.P.; and Dr. Thomas Wickham, 2020 graduate of the University of New England College of Osteopathic Medicine transitioning to a Family Medicine residency at UMass Memorial Medical Center.

About NRMP
The National Resident Matching Program® (NRMP®) is a private, non-profit organization established in 1952 at the request of medical students to provide an orderly and fair mechanism for matching the preferences of applicants for U.S. residency positions with the preferences of residency program directors. In addition to the annual Main Residency Match® for almost 44,000 registrants, the NRMP conducts Fellowship Matches for more than 60 subspecialties through its Specialties Matching Service® (SMS®).

Monday, June 22, 2020

Raj Chetty nowcasts Covid-19

Here is Raj Chetty on what the covid-19 market shock looks like pretty much as it is happening... his talk starts at 13.20, after an introduction by Markus Brunnermeier.


Sunday, June 21, 2020

Who are U.S. essential workers in the coronavirus lockdowns? McCormack, Avery, Spitzer and Chandra in JAMA

Here's a paper in JAMA that focuses on households with essential workers, many of whom are low income.   40% of adult workers are classified as essential workers, and a quarter of them earn less than $40,000.

McCormack G, Avery C, Spitzer AK, Chandra A. Economic Vulnerability of Households With Essential Workers. JAMA. Published online June 18, 2020. doi:10.1001/jama.2020.11366

"We analyzed data from the Public Use Microdata Sample of the 2018 American Community Survey (ACS). The US Census Bureau chooses a random sample of US addresses each month, contacts selected households by mail, and follows up by phone and personal visit to address nonresponse.3 The Department of Homeland Security’s Cybersecurity and Infrastructure Security Agency (CISA) released an “Essential Critical Infrastructure Workforce” advisory list of occupations necessary to “continuity of functions critical to public health and safety” in March 2020 and updated that list in April 2020.4 We matched industry and subindustry codes in the ACS to the 6-digit Standard Occupation Codes (indexed by the US Bureau of Labor Statistics) in the CISA advisory list to identify essential workers.5 We assessed the proportion and demographic characteristics (age, sex, race as given in response to a multiple-choice question) of essential workers by industry."




"Eight of the 21 industry categories from the ACS accounted for 73% of essential workers. Health care accounted for a larger proportion (15%) of essential workers than any other industry: 65% of health care workers held essential jobs. Black individuals were overrepresented in several essential industries, notably transportation (23%), public administration (18%), and health care (18%).

"A total of 1 410 976 households were represented in the 2018 ACS with an estimated 51% of those households including an essential worker. Table 2 summarizes household characteristics of essential workers: 25% of essential workers were estimated to have low household income, 18% to live in a household with at least 1 uninsured person, and 18% to live with someone 65 years or older. We estimated that 48% of essential workers lived in a household with at least 1 risk and 13% of essential workers lived in high-risk households."