Cascades of convalescent plasma for Covid-19, and chains of exchanges, by Kominers, Pathak, Sönmez, and Ünver

Covid-19 convalescent plasma is a new thing in the world, that came into existence only when the first human was infected and recovered from the Covid-19 disease that is now pandemic. It isn't clear yet whether it will be clinically valuable, but recovered antibodies have been valuable for some other diseases, so there's excellent reason to hope that will be the case now too.  And as the number of people grows who have recovered from Covid-19, it is likely that the supply of antibodies is growing much faster, since antibody-containing plasma can be donated once a month or so. (There are  ongoing studies of antibody production by recovered patients, examining how long the antibodies remain at high levels, post-recovery). Of course, most of that supply is sequestered in the blood of recovered patients, so there's a non-trivial issue of collection and distribution.

As readers of this blog know, many countries prohibit the sale of plasma. Will Americans continue to support a commercial market for Covid-19 convalescent plasma in the current pandemic?  A distinguished group of market designers has written a paper considering how to apply techniques developed for kidney exchange to the task of collecting convalescent plasma from recovered Covid-19 patients, if it becomes impossible to buy and sell it. In particular, they consider how to create chains of donations, without using money, to overcome the shortages they anticipate.

Here's an easy to read account by Scott Kominers, one of the authors.

How to End the Plasma Shortage for Coranavirus Patients

Scott Duke Kominers, Bloomberg News  May 11, 2020

"convalescent plasma is in short supply: although it’s hard to estimate precisely, some statistics suggest the U.S. may need twice as much as we have on hand.

"In a new paper, Parag A. Pathak, Tayfun Sonmez, M. Utku Unver and I propose a market design strategy that could help close the gap. Our approach makes use of two special features of the way plasma donation works.

"First, convalescent plasma is collected from recently recovered patients, which means that today’s patients become tomorrow’s prospective donors, assuming they manage to beat the virus. ... That suggests the shortage isn’t from lack of potential supply.

"Second, plasma donation is more than one-for-one: the typical donor can give enough plasma at one time for multiple treatments, and they can potentially donate more than once. As a result, assuming plasma therapy does help patients recover, there is a so-called flywheel effect: the more we use the treatment, the more plasma is available -- provided enough recovered patients are willing to donate.

"Many people would like to donate plasma to help a loved one, but can’t for various reasons:  Their blood types might be incompatible or they might live far away and be unable to travel. To address these sorts of obstacles, my collaborators and I suggest that each plasma donor could receive a voucher that can be used to give a family member or friend priority for plasma treatment. Because donation is more than one-for-one, it’s possible to honor vouchers while still increasing the pool of plasma available to treat other patients.

...

"A similar analysis suggests a role for a pay-it-forward system, where we make a point of treating patients who pledge to donate plasma, assuming they recover and are medically able to do so. Because recovered patients can typically donate more plasma than was needed for their own treatment, this again can help increase the plasma supply in the long run. As a result, my collaborators and I show that, somewhat paradoxically, prioritizing patients who pledge to donate can still end up expanding treatment for the patients who are unable to pledge, or just choose not to.

"Both of these policies are similar to systems we’ve used to expand kidney donation in the U.S.: Priority vouchers are sometimes granted when a living donor gives a kidney to a third-party before one of their family members needs a transplant. And pay-it-forward incentives are used in kidney exchange chains, where a patient with a medically incompatible prospective donor receives a kidney from a third-party donor, and then their donor later gives a kidney to some other patient."
******
Here is the paper itself:

Paying It Backward and Forward: Expanding Access to Convalescent Plasma Therapy Through Market Design
Scott Duke Kominers, Parag A. Pathak, Tayfun Sönmez, M. Utku Ünver
NBER Working Paper No. 27143
Issued in May 2020

Abstract: COVID-19 convalescent plasma (CCP) therapy is currently a leading treatment for COVID19. At present, there is a shortage of CCP relative to demand. We develop and analyze a model of centralized CCP allocation that incorporates both donation and distribution. In order to increase CCP supply, we introduce a mechanism that utilizes two incentive schemes, respectively based on principles of “paying it backward” and “paying it forward.” Under the first scheme, CCP donors obtain treatment vouchers that can be transferred to patients of their choosing. Under the latter scheme, patients obtain priority for CCP therapy in exchange for a future pledge to donate CCP if possible. We show that in steady-state, both principles generally increase overall treatment rates for all patients—not just those who are voucher-prioritized or pledged to donate. Our results also hold under certain conditions if a fraction of CCP is reserved for patients who participate in clinical trials. Finally, we examine the implications of pooling blood types on the efficiency and equity of CCP distribution.

Here's some of the motivation for their model:

"There is an active debate in economics and philosophy on the appropriate role of market-based

mechanisms with compensation for human products used in medicine or medical research like kidneys, blood, blood products, sperm, breast milk, bone marrow, and other.11 Since, as far as we know, there is no current market where infected patients can buy CCP or where recovered patients can sell CCP, we do not consider this possibility as part of our model.

...

"Because CCP is a form of plasma, a natural question is whether a compensated market for CCP will develop. In our model, there is no option to pay to receive CCP or be paid for donating CCP, but a donor can designate the voucher in our model to particular patient in need. As a result, our model of CCP falls between the two extremes described above. We expect that in a crisis moment, there is unlikely to be an active compensated market for CCP (even though it may be impossible to fully prohibit resale of vouchers). If a price-based market does develop, society may deem it unacceptable."

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

I am more optimistic than they are about the likely available supply of convalescent plasma if it proves useful, through existing commercial channels. My optimism is based on the large thriving commercial market for plasma and plasma-derived antibodies in the U.S., and around the world.  I'll try to blog about the general plasma and antibody (immunoglobulin) market tomorrow, and perhaps more on Covid-19 antibodies later this week.

Transplants dropped as Covid-19 rose, in France and the U.S.

In France, even more than in the U.S., kidney transplants were considered elective surgery.

In the Lancet:

Organ procurement and transplantation during the COVID-19 pandemic
Alexandre Loupy, Olivier Aubert, Peter P Reese, Olivier Bastien, Florian Bayer, Christian Jacquelinet
Published:May 11, 2020

Here is a set of figures showing "Trends in COVID-19 spread over time in France and the USA and recovery of organs and solid-organ transplantation procedures from deceased donors" (The top two figures are France, the bottom two US)

Here's an updated snapshot of American transplants from UNOS, for all organs:

and for kidneys:

Search and matching models of marriage (with emphasis on search or on matching)

Often when economic theorists (particularly matching theorists) speak of "marriage" we don't mean the real thing, we mean a metaphor embodied in a simple one-to-one model of matching. But marriage is a very real thing, and matching models of various sorts are used to study it.  Here's a survey from the Annual Review of Economics, by one of the leaders of this literature.

The Theory and Empirics of the Marriage Market by  Pierre-André Chiappori

"the economic analysis of the marriage will aim at answering two sets of questions: (a) Who marries whom? and (b) How are the benefits distributed between spouses? Mostly, these questions have been analyzed using either of two different frameworks: frictionless matching theory and search models. The basic distinction between the two is related to the emphasis that is put (or not) on frictions in the description of the market. In search models, frictions are paramount. Typically, each individual sequentially and randomly meets one person of the opposite gender; after such a meeting, both individuals must decide whether to settle for the current mate or continue searching. The latter option involves various costs, from discounting to the risk of never finding a better partner. If both individuals agree to engage in a relationship (which can be marriage or, in some models, cohabitation), then a negotiation begins on the way the surplus is shared.

"Matching models, on the contrary, assume a frictionless environment. In the matching process, each woman (say) is assumed to have free access to the pool of all potential men, with perfect knowledge of the characteristics of each of them—and vice versa. In other words, matching models disregard the cost of acquiring information about potential matches as well as the role of meeting technologies of all sorts (from social media to head hunters and from dating sites to pure luck).
*********

I haven't absorbed the whole paper yet, but the introduction reminded me of the plurality of approaches to studying search and matching (not just restricted to the study of marriage). Chiappori shares the view that the big difference between search models and matching models is that matching models are "frictionless," they assume away all the search frictions that are the subject of search models. 

Search models, on the other hand, concentrate on search effort, and take the actual matching technology to be random meetings. (To my mind, that's vastly different from taking account of the actual technology of matching, which is central to the market design literature on matching.)

The 2010 Nobel prize in Economics went to Diamond, Mortensen, and Pissarides, the founders of the search and matching macro literature "for their analysis of markets with search frictions." I recall that Dale Mortensen expressed the view that one of their big contributions was to notice that matching could be regarded as a "black box," rather than being studied explicitly, i.e. that actual matching didn't need to be incorporated in the model. Here's a 2001 paper from the JEL that discusses that:

Looking into the Black Box: A Survey of the Matching Function
Barbara Petrongolo and Christopher A. Pissarides
Journal of Economic Literature Vol. 39, No. 2 (Jun., 2001), pp. 390-431

" The matching function summarizes a  trading technology between agents who  place advertisements, read newspapers and  magazines, go to employment agencies,  and mobilize local networks that eventually bring them together into productive matches. The key idea is that this  complicated exchange process is summarized by a well-behaved function that  gives the number of jobs formed at any  moment in time in terms of the number  of workers looking for jobs, the number  of firms looking for workers, and a  small number of other variables.

" The matching function is a modeling  device that occupies the same place in  the macroeconomist's tool kit as other  aggregate functions, such as the production function and the demand for money  function."
***********
That work, which is focused on search and which treats matching as a black box, provides some big insights. For example, if search is costly but the benefits of matching are shared equally by the one who searches and the one who is found, then there can be free riding in the form of too little search, and hence unemployment by qualified job seekers at the same time that there are unfilled positions, and unsold houses at the same time as there are people who would actually like to buy them.

But models of matching via aggregate matching functions or via random matching are nowhere near the level of detail that allows the kind of micro-micro economics that market designers practice in analyzing marketplaces or in trying to design them. I'm mostly talking about markets that resemble labor markets more than marriage, but dating sites are marketplaces designed for something related to marriage, and there are some explicitly matrimonial sites. Much of what makes one dating site different from another is how they deal with congestion and other frictions.

A not-atypical market design project begins with an analysis of matching in an existing system,  focused on precisely the details of how matching occurs. A next step is that designers sometimes take responsibility for redesigning those details, or aspects of them, to reduce frictions in marketplaces e.g. for labor, schools,  kidneys, MBA courses, financial exchanges, dating sites themselves, etc.

I think there has been too little intersection between those who study search with random matching and those who study matching without explicitly modeling the costs of search. (That isn't to say that there aren't people working and making progress in that intersection.)  Possibly one barrier is a misunderstanding between these two groups of what the models are good for.

Does the porn industry provide a model for disease testing and contact tracing to end corona virus lockdowns?

The adult film industry--which produces films in which performers engage in sex with one another--has a testing service called PASS (Performer Availability Screening Services) intended to control the spread of sexually transmitted diseases on film sets.

"Testing facilities screen patients for HIV using the Aptima HIV-1RNA Qualitative Assay test. Other tests on a full performers’ panel also include Chlamydia, gonorrhea, hepatitis B & C, trichomoniasis, and syphilis."
********

Stat provides some detail:
Why the porn industry has a lot to teach us about safety in the Covid-19 era
By USHA LEE MCFARLING  MAY 8

"Since the late 1990s, when an outbreak of HIV infections threatened to shutter the multibillion-dollar industry, the mainstream porn community has implemented procedures that require all performers to be tested for HIV and a host of other sexually transmitted infections every 14 days before they can be cleared to work. Any HIV-positive test leads to an immediate shutdown of all U.S. sets, followed by detailed contact tracing before sets can reopen.
...
"In the 20 years it has been in place, PASS has met, and overcome, many of the same challenges that any large-scale coronavirus testing program might encounter, from issues of keeping databases of private medical information secure, preventing the forging of test results, dealing with false positive results, and educating workers about the need for repeated testing to keep workplaces safe.
...
"“You could imagine TSA verifying someone had tested negative before they were allowed on a flight,” he said. “Testing is particularly important for areas that are high risk, like airplanes or meatpacking plants.”
...
"Mike Stabile, communications director for the Free Speech Coalition, the adult entertainment trade association that runs PASS, said the adult film industry understands “better than most the discussion that has to happen for businesses to reopen.”

"Yet for all of that expertise, it would be hard to imagine the Trump administration, or state politicians, reaching out to the porn industry for guidance.
...
"Repeat testing will be necessary for the coronavirus, too, because — like with HIV — there is so much asymptomatic spread of the coronavirus, said Elizabeth “Betz” Halloran, a professor of biostatistics at the University of Washington who directs the Center for Inference and Dynamics of Infectious Diseases at the Fred Hutchinson Cancer Research Center in Seattle.

“You’ll have to keep testing, maybe every 10 days. We need simpler tests that people can just do at home,” said Halloran, who envisions a low-cost “10-pack” of tests for home use."

College admissions, late in the season

Each year, around this time of year, as the main round of college admissions comes to a conclusion, NACAC (the National Association for College Admissions Counseling) publishes a list of colleges that still have positions for qualified students.  Here's this year's listing:

COLLEGE OPENINGS UPDATE: OPTIONS FOR QUALIFIED STUDENTS

"NACAC’s annual College Openings Update: Options for Qualified Students (formerly the Space Availability Survey) is a voluntary listing of NACAC member postsecondary institutions that are still accepting applications from prospective freshman and/or transfer students for the upcoming fall term. Now in its 33rd year, the College Openings Update is designed as a tool for counselors, parents and others assisting students who have not yet completed the college admission process. Typically, colleges will continue to join the update after the May 5 public release date, so check back periodically to see additional colleges still accepting applications."

Confusion in NYC high school wait lists

In August, the New York City Department of Education announced a change in the school choice assignment process--without announcing any details.  But the plan was that after the initial run of the deferred acceptance algorithm, they would institute some sort of wait lists. I blogged about it at the time, and was concerned by the lack of detail.

Here's a current story from Chalkbeat that suggests that the details are still opaque, but that families are learning that the waitlist position they were given isn't reliable:

‘How can you move back on a waiting list?’: NYC’s high school admissions tweaks spark confusion
By Alex Zimmerman  May 8, 2020

"students vying for the city’s most coveted schools are discovering that their position on high school waitlists can worsen over time, a situation that has come as a surprise to some families — adding anxiety to an admissions process that is already famous for its complexity.
...
"Every student who fills out an application and does not get into their top choice is automatically waitlisted. If you get your third choice school, for example, you’ll be on the waitlist for your No. 1 and 2 choices. Nearly 44,000 students did not get into their first choice high school this year, automatically placing them on at least one waitlist.

"The second way is that students can add themselves to any waitlist once the initial matching process is over, even for schools a student didn’t initially apply to.

"In general, students who initially applied to a school but didn’t get in and are automatically added to its waitlist should be ranked ahead of students who add themselves later on, officials said. But there are exceptions.

"The first major exception is if a student is in a higher priority group than someone who is already on the waitlist. Some schools, for instance, give preference to students who live in certain neighborhoods, which can override a student’s position on the waitlist even if they were added first. (Officials said this is the most common reason a student would see their position worsen.)

"Olga Ramos, the admissions director at Bard High School Early College Queens, pointed to a second reason families can move backward — something that surprised her at first.

"If a student got into their first choice school, and listed Bard as their second choice, they could still add themselves to Bard’s waitlist and be considered as if they had been automatically added — potentially bypassing students who were already on the list."

*********
Here's an earlier story in Chalkbeat by Mr. Zimmerman, indicating that the system was still pretty opaque as the school choice process got ready to announce admissions in March:

NYC high school offers are coming this week with a big change: waitlists. Here’s what you should know.  By Alex Zimmerman  Mar 18, 2020

Here's what was known then...

"What are these waitlists, anyway?

"New York City students must apply to high school, listing up to 12 schools they want to attend. A complicated algorithm, developed by a Nobel prize-winning economist, then matches a student to one of their choices.

"That fundamental algorithm is not changing. But for the first time this year, any student who does not get into their first choice school will automatically be added to the waitlist of every single higher-ranked school they didn’t get into.

"Every school that has more applicants than seats will have a waitlist. It’s a similar model that the education department uses for pre-K, kindergarten, and middle schools — something education department officials said is an advantage."

**********
Here's a story from the time of the initial announcement:

Goodbye round two applications, hello waitlists: NYC announces changes to high school admissions
By Christina Veiga and Alex Zimmerman   Aug 15, 2019

"Starting next year, the city will allow students to sit on waiting lists for schools they wanted to attend, but didn’t get into. The city is also eliminating the second round of admissions, which it now uses to for students who aren’t matched to a school they applied to during the typical process.
...
"“It’s like going to a store and getting the ticket, you know what number you are, and you know how many folks are ahead of you, and you’ll be able to watch the process go,” said Deputy Chancellor Josh Wallack. “You’ll also be able to talk with an administrator in a school who can give you a sense of how much waitlists move each year and that varies a bit by school.”
*****

I'm still confused about a different issue that I haven't yet seen addressed. In the original school choice system using the deferred acceptance algorithm, there was a second round in which students unmatched in the first round were asked for additional preferences over schools, so that they could be matched.  How were those unmatched students assigned to schools this year?

Here's my August post:

Friday, August 16, 2019 

Waitlists in NYC school choice--early reflections on yesterday's initial announcements

Double bubble: Locking up with exactly one other household during lock down

You thought your hard interpersonal decisions ended in high school, or when you married?  Not if you live in parts of Canada, where households will now be allowed to expand their social-distancing radius to include exactly one other household.

The WP has the story:

Canadian provinces allow locked-down households to pair up — threatening hurt feelings all around

"While jurisdictions around the world begin to relax their coronavirus restrictions, a handful are pioneering a novel — and potentially fraught — approach: The double bubble.

"There are rules — and they are not for the commitment-phobic. Each household may join with only one other household. Both sides must agree — for better, for worse — to a mutually exclusive relationship. The decision applies to all members of both households. And it’s final.
...
"The arrangement isn’t unique to Newfoundland and Labrador. New Brunswick has also introduced it. So has New Zealand. And the English Channel island of Guernsey.

Buying and selling blood plasma, with focus on Canada, continued

Peter Jaworski writes:

"I had a video with Big Think come out recently where I defend paying for plasma against a number of objections. It’s a bit on the long side (17 minutes), but I thought you might be interested in posting it to your blog: https://bigthink.com/videos/paid-plasma-ethics

"I also had an opinion piece on the same topic published in the National Post (with Kate Vander Meer, who is a patient that used plasma therapies): https://nationalpost.com/opinion/opinion-on-covid-19-canada-needs-to-pay-plasma-donors-to-protect-its-domestic-supply?video_autoplay=true"

From the video transcript:

"Out of all the countries in the world only the ones that pay people to make that donation are self-sufficient in plasma therapies. And even the ones that pay not all of them are, in fact, sufficient. So there are only seven countries in the world that legally permit paying people for plasma donations – Germany, Austria, Hungary, Czechia or the Czech Republic, parts of Canada. And I'll talk about Canada in a second. The United States, of course, and China. Those are the seven countries in the world that permit payment. Every other country that does not allow payment for plasma donations imports plasma therapies that make use of plasma primarily from Americans. Germans as well, but primarily Americans. "
***********
And here's the op-ed:

Opinion on COVID-19: Canada needs to pay plasma donors to protect its domestic supply
Kate Vander Meer and Peter Jaworski: In order to ensure that enough people are willing to give plasma to meet the ever-expanding need, we must urgently adopt a pay-for-plasma model here at home

"There’s no evidence that anything other than paying for plasma will work. According to an expert panel formed by Health Canada in 2018, paid donors in countries that permit payment are responsible for providing 89 per cent of the plasma used to make therapies, with the United States alone providing 70 per cent of the global supply. The panel also revealed that no country in the world that forbids paid donations collects enough plasma to meet its needs — not one!"

Repugnant but legal: can strip shows and payday lenders get Paycheck Protection Program support in the pandemic?

The Washington Post has the story:

Strip clubs, payday lenders, lobbyists fight to get emergency federal loans
In wave of lawsuits, companies battered by coronavirus shutdowns but excluded from aid seek small-business funds

"The Little Darlings strip club in Flint, Mich., was forced to turn off its stage lights and close its doors by the state’s stay-at-home order, but it failed to get a federal small-business emergency loan aimed at softening the financial blow from the pandemic.

"Owners of Little Darlings, along with clubs such as Baby Dolls in Dallas and Cheerleaders Gentlemen’s Club in Philadelphia, said it was wrong that they were excluded from the more than $600 billion Paycheck Protection Program created by Congress and the Trump administration to try to save businesses and jobs during the coronavirus crisis.

"So the strip clubs sued the Small Business Administration. And a federal judge in Wisconsin recently sided with the strip clubs, granting a preliminary injunction to force the government to issue loans to four of them, which government lawyers quickly appealed."

Human Challenge Trials (aka Controlled Human Infection studies) for corona virus vaccines

What do we want?  A vaccine for covid-19.

When do we want it?  After clinical trials and peer review.

How can we get it faster?  By asking healthy young (not at too much risk) volunteers to permit themselves to get infected with covid-19, so we can try out vaccine candidates.

Is that crazy?  Well, maybe not. (But not everyone is sure of that.)

Here's a recent paper considering the proposal.

Human Challenge Studies to Accelerate Coronavirus Vaccine Licensure 
Nir Eyal, Marc Lipsitch, Peter G Smith
The Journal of Infectious Diseases, jiaa152, https://doi.org/10.1093/infdis/jiaa152
Published: 31 March 2020

Abstract: Controlled human challenge trials of SARS-CoV-2 vaccine candidates could accelerate the testing and potential rollout of efficacious vaccines. By replacing conventional phase 3 testing of vaccine candidates, such trials may subtract many months from the licensure process, making efficacious vaccines available more quickly. Obviously, challenging volunteers with this live virus risks inducing severe disease and possibly even death. However, we argue that such studies, by accelerating vaccine evaluation, could reduce the global burden of coronavirus-related mortality and morbidity. Volunteers in such studies could autonomously authorize the risks to themselves, and their net risk could be acceptable if participants comprise healthy young adults, who are at relatively low risk of serious disease following natural infection, if they have a high baseline risk of natural infection, and if during the trial they receive frequent monitoring and, following any infection, the best available care.
*************

Here's another paper, in Science, 07 May 2020, by a big group of authors consisting of medical ethicists and physicians: they think it might be ok.

Ethics of controlled human infection to study COVID-19
Seema K. Shah, Franklin G. Miller, Thomas C. Darton, Devan Duenas, Claudia Emerson, Holly Fernandez Lynch, Euzebiusz Jamrozik, Nancy S. Jecker, Dorcas Kamuya, Melissa Kapulu, Jonathan Kimmelman, Douglas MacKay, Matthew J. Memoli, Sean C. Murphy, Ricardo Palacios, Thomas L. Richie, Meta Roestenberg, Abha Saxena, Katherine Saylor, Michael J. Selgelid, Vina Vaswani, Annette Rid

 Abstract: High social value is fundamental to justifying these studies

 Here are the articles opening lines:

"Development of an effective vaccine is the clearest path to controlling the coronavirus disease 2019 (COVID-19) pandemic. To accelerate vaccine development, some researchers are pursuing, and thousands of people have expressed interest in participating in, controlled human infection studies (CHIs) with severe acute respiratory syndrome–coronavirus 2 (SARS-CoV-2) (1, 2). In CHIs, a small number of participants are deliberately exposed to a pathogen to study infection and gather preliminary efficacy data on experimental vaccines or treatments. We have been developing a comprehensive, state-of-the-art ethical framework for CHIs that emphasizes their social value as fundamental to justifying these studies. The ethics of CHIs in general are underexplored (3, 4), and ethical examinations of SARS-CoV-2 CHIs have largely focused on whether the risks are acceptable and participants could give valid informed consent (1). The high social value of such CHIs has generally been assumed. Based on our framework, we agree on the ethical conditions for conducting SARS-CoV-2 CHIs (see the table). We differ on whether the social value of such CHIs is sufficient to justify the risks at present, given uncertainty about both in a rapidly evolving situation; yet we see none of our disagreements as insurmountable. We provide ethical guidance for research sponsors, communities, participants, and the essential independent reviewers considering SARS-CoV-2 CHIs."

Kim Krawiec points out to me that, among the things the authors disagree about among themselves is compensation to donors:
"Members of our group disagree about the ethical permissibility of offering payment to CHI participants, and there may be relevant regulatory limits in different jurisdictions. Nevertheless, as SARS-CoV-2 CHIs require confinement and follow-up, fairness seems to demand offering participants compensation for their time. This may total several thousand dollars in the United States, assuming compensation at a fair minimum wage for unskilled labor, as in other CHIs. By contrast, incentives beyond compensation could be avoided, given the number of people already indicating willingness to participate. Concerns that the undue influence of monetary compensation compromises risk judgments are unsupported by the available data, as financial motivations are associated with greater attention to risk (15). Moreover, a rigorous informed consent process could maximize understanding. In case payment tempts participants to withhold disqualifying information, eligibility criteria should be objectively verifiable."
************

And here is a group of activists, at an organization called 1 Day Sooner.
You can sign up here*,

COVID-19 Human Challenge Trials
"Human challenge trials deliberately expose participants to infection, in order to study diseases and test vaccines or treatments. They have been used for influenza, malaria, typhoid, dengue fever, and cholera. Researchers are exploring whether human challenge trials could speed up the development of a vaccine for COVID-19, saving thousands or even millions of lives."

*"Sign up here if you may wish to participate in a human challenge trial for COVID-19 if one were to occur, and, potentially, advocate for safe and rapid vaccine development. "

Price versus waiting time in a ride sharing market

Here's an interesting paper on ride sharing, with estimates of the tradeoffs that individuals make between price and waiting time. The data come from the Uber-like ride sharing service Liftago in the Czech Republic, which however offers passengers a tradeoff between price and waiting time.

THE VALUE OF TIME: EVIDENCE FROM AUCTIONED CAB RIDES
Nicholas Buchholz, Laura Doval, Jakub Kastl, Filip Matějka, Tobias Salz
Working Paper 27087  http://www.nber.org/papers/w27087

ABSTRACT: We estimate valuations of time using detailed consumer choice data from a large European ride hail platform, where drivers bid on trips and consumers choose between a set of potential rides with different prices and waiting times. We estimate consumer demand as a function of prices and waiting times. While demand is responsive to both, price elasticities are on average four times higher than waiting-time elasticities. We show how these estimates can be mapped into values of time that vary by place, person, and time of day. Regarding variation within a day, the value of time during non-work hours is 16% lower than during work hours. Regarding the spatial dimension, our value of time measures are highly correlated both with real estate prices and urban GPS travel flows. A variance decomposition reveals that most of the substantial heterogeneity in the value of time is explained by individual differences as opposed to place or time of day. In contrast with other studies that focus on long run choices we do not find evidence of spatial sorting. We apply our measures to quantify the opportunity cost of traffic congestion in Prague, which we estimate at $483,000 per day.

In the body of the paper they say:

"We use detailed consumer choice data from Liftago, a large European ride-hailing application. This platform uses a unique mechanism to allocate each ride through a rapid auction process in which nearby drivers bid on ride requests and requesting consumers choose between bids based on various characteristics. Most importantly, bids often involve tradeoffs between price and waiting time, or the time it would take the taxi to pick up the customer. Contrast this with platforms like Uber and Lyft that employ “surge” pricing to equilibrate demand and supply so that consumers do not get to directly express their preferences over prices and waiting times within the platform. We are able to observe both consumers’ individual choice sets as well as their ultimate selection for 1.9 million ride requests and 5.2 million bids.

"The first contribution of this paper is to provide a direct and clean measurement of consumers’ willingness-to-pay to reduce waiting times. We use the variation in choice sets and choices to estimate a demand system that depends both on prices and waiting times. Such measures are of first-order importance for the provision of public transportation infrastructure as well as for the ride hail industry where price and waiting time are the two key variables on which firms compete. Our setting allows us to overcome some of the empirical challenges in measuring preferences over both prices and waiting-time.

"Our second contribution, building on the work of Small (1982), is to provide a conceptual  framework to interpret the disutility of waiting and to demonstrate how the willingness-to-pay for waiting-time reductions can be used to recover the value of time. When consumers choose a shorter wait time over a lower price, they reveal that the value of their time at a particular destination and time-of-day is greater than the value at the original location. Intuitively, the willingness to pay for lower wait times is simply the difference between the value of time at the destination and the value of time at the origin. "

**********

I think the first contribution mentioned above is quite an accomplishment, since I don't know of any equally good measure of consumer preferences for waiting time versus price.

I have some reservations about the value of shorter waiting time being a measure of the value of time at the destination minus the value of time at the origin. That seems to me to be a bit complicated. If I'm at work, ready to go home, and I expect waiting time to be not too long, I might go out of my building before calling a car (and now my value of time where I am is quite low). If I thought the waiting time would be longer, I might call the car from my office, where my value of time could be pretty high.  So the value of time "where I am" depends on whether I'm working or just waiting...and that depends on how long I think I'll have to wait.

Testing (for virus and/or antibodies) as a component of ending corona pandemic lockdowns

Yesterday I wrote about how contact tracing could play a big role in relaxing corona pandemic lockdowns.  How about very large scale testing for corona virus? Clearly, it's not one or the other, but one can imagine, and some do, that testing essentially everyone, frequently, could remove the need for indirect methods like tracing contacts.

There are two main things we could test for: virus (infection) and antibodies (indication of past infection).

The main test so far for virus infection, recommended by the CDC, is called a nasopharyngeal swab. It's uncomfortable, but more in a surprising way than a painful one (I am a veteran, and it is surprising how far into your skull your nose goes...). More importantly, it is hazardous for the testers, who could be exposed to the virus while they are probing noses where it lurks.  So they need to be in full hazmat garb, masked and gowned.  And the test I had was not in the hospital or one of the medical office buildings, but on the second floor of the adjacent parking garage (a drive-through test) so that no patients or health care workers or surfaces they might touch would be exposed to infection.

That means the test is hard to administer to many people, or frequently.

Paul Romer argues that the road to ending lockdowns should have every American  tested every two weeks.

It appears that more convenient tests that are also less likely to spread the disease are becoming available.  Here's a story from the WSJ about a saliva test that would allow testees to spit into something and seal it up without exposing the world to possible infection:

Your Spit Could Be the Best Coronavirus Test
As states look for ways to increase their testing capacity, new research suggests that saliva is as effective detecting the virus as swabs

"spitting into a cup appears to be as effective at detecting this virus as sticking a swab into your nose."
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Another kind of testing involves blood tests for antibodies to Covid-19. The hope is that individuals with antibodies have acquired substantial immunity to the disease (and hence could return to work). But so far little is known about how much immunity for how long follows recovery from Covid-19, so doubts are emerging about how much can be learned from antibody tests at present.

From the NY Times
Italians Find Promise of Antibodies Remains Elusive, for Now
Talk of licensing people with the right antibodies, always ahead of the science, has faded as experts warn that they are still studying what level offers protection and how long it lasts.
By Jason Horowitz

and in the Lancet:

COVID-19 immunity passports and vaccination certificates: scientific, equitable, and legal challenges

Alexandra L Phelan  Published:May 04, 2020

"Individuals in possession of an immunity passport could be exempt from physical restrictions and could return to work, school, and daily life. However, immunity passports pose considerable scientific, practical, equitable, and legal challenges.

"On April 24, 2020, WHO highlighted current knowledge and technical limitations, advising “[t]here is currently no evidence that people who have recovered from COVID-19 and have antibodies are protected from a second infection…[a]t this point in the pandemic, there is not enough evidence about the effectiveness of antibody-mediated immunity to guarantee the accuracy of an ‘immunity passport’”.

Contact tracing as a component of ending corona pandemic lock-downs

One important idea behind 'flattening the curve' of covid-19 cases is that, if lockdowns reduce the case rate sufficiently, the economy might be able to open up again and leave control of the virus to contact tracing and selective quarantines.  Contact tracing--tracing the contacts of sick people, to see who else they might have infected--was the go to method of trying to control sexually transmitted diseases.  But it's likely that an infected person has an easier time remembering sexual contacts than the much more casual contacts than can lead to covid-19 infection.

And there are lots of ideas about how contact tracing might be conducted (and it isn't clear to me that any of them are being prepared for with sufficient seriousness to be actually put into place anytime soon...). The old fashioned way involves lots of people on the phone, interviewing those who have just tested positive.

Here's one story along that line, from The Hill:
Newsom wants to train 10,000 contact tracers in California

"California Gov. Gavin Newsom (D) said Wednesday that the state is planning to train up to 10,000 contact tracers amid the coronavirus pandemic.

"Expanding contact tracing and testing is one of six indicators Newsom said last week would drive the state’s decision to gradually modify portions of the stay-at-home order. "


And here's another, from Vox:
Contact tracing, explained
The US needs tens of thousands of “disease detectives” to safely reopen the economy.   
By Dylan Scott

"To prevent another spike in cases, public health workers will perform the difficult and sometimes tedious process of interviewing people diagnosed with Covid-19, finding out who they have recently been in close physical contact with, and then informing those people of their potential exposure and advising them to self-isolate and get tested.

“The rapidity with which this work has to be done is really unprecedented,” Jeff Dunchin, who leads the epidemiology division in King County, Washington, the first epicenter of the pandemic in the United States, told me. “If you miss a few cases, those little sparks can set off a forest fire.”
***************

Another part of the contact tracing discussion involves apps on smart phones. The idea is that your phone can report to a good deal of precision where you have been, and/or who you have been near.  That "and/or" has implications for privacy.  If the contact tracers figure out if you and I have been near each other by looking at our path through the world, then they are recording a lot of information about us besides whether we have e.g. been within six feet of each other.  Alternatively, using blue tooth enabled apps, we could just be recording which phones our phone got close to.

In either case, the idea behind phone apps for contact tracing is that if someone tests positive for covid-19, they record it on their app, go into quarantine themselves, and the apps of everyone to whom they have been close (in the last 14 days?) sound the alarms.

Here's a paper in Science:

Quantifying SARS-CoV-2 transmission suggests epidemic control with digital contact tracing
Luca Ferretti *, Chris Wymant *, Michelle Kendall , Lele Zhao , Anel Nurtay , Lucie Abeler-Dörner ,
Michael Parker , David Bonsall1,†, Christophe Fraser1,†‡

Abstract: The newly emergent human virus SARS-CoV-2 is resulting in high fatality rates and incapacitated health systems. Preventing further transmission is a priority. We analyzed key parameters of epidemic spread to estimate the contribution of different transmission routes and determine requirements for case isolation and contact-tracing needed to stop the epidemic. We conclude that viral spread is too fast to be contained by manual contact tracing, but could be controlled if this process was faster, more efficient and happened at scale. A contact-tracing App which builds a memory of proximity contacts and immediately notifies contacts of positive cases can achieve epidemic control if used by enough people. By targeting recommendations to only those at risk, epidemics could be contained without need for mass quarantines (‘lock-downs’) that are harmful to society. We discuss the ethical requirements for an intervention of this kind.
************

Here's a skeptical take on that from Brookings Techstream, that focuses on the considerable problem of false positive and false negative conclusions, and also on privacy and security:

Contact-tracing apps are not a solution to the COVID-19 crisis
April 27, 2020 Ashkan Soltani, Ryan Calo, and Carl Bergstrom

"we urge developers of contact-tracing apps, as well the companies enabling their development, to be candid about the limitations and implications of the technology. To be ethical stewards of these new public health tools, they must also provide explicit guidelines and “best practice” recommendations for the development of the apps. These should include recommendations for how back-end systems should be secured and how long data should be retained, criteria for what public health entities can qualify to use these technologies, and explicit app store policies for what additional information, such as GPS or government ID numbers, can be collected. They should adopt commonly accepted practices such as security auditing, bug bounties, and abusability testing to identify vulnerabilities and unintended consequences of a potentially global new technology. Finally, app creators—as well as the platforms that enable these applications—should make explicit commitments for when these apps and their underlying APIs will be sunsetted.

"There is also a role for law and official policy. If we are to use technology to combat coronavirus, it is critical that we do so with adequate safeguards in place. Here we mean traditional safeguards, such as judicial oversight and sunset provisions that guard against mission creep or limitations on secondary use and data retention that protect consumer privacy. We agree with our colleagues at the Civil Liberties Oversight Board that coronavirus surveillance should learn from the lessons of 9/11. But we also see a role of law and policy in policing against an all too plausible dystopia that technological solutions could enable."
*************

If you are in Australia, here's a government sponsored voluntary contact tracing app that you could try out if you want:
COVIDSafe app
Let's work together to stop the spread of COVID-19
COVIDSafe helps you and all of our communities. Assist health officials to quickly understand and tackle the spread of Coronavirus (COVID-19).
https://www.covidsafe.gov.au/

***********
And here is (a picture) of the above post in Spanish, in the (gated) 20th anniversary edition of the magazine Capital:  Capital cumple veinte años

Transplants under lockdown (but beginning to pick up)

Since the beginning of pandemic lockdowns, living donor kidney surgeries in the U.S. have almost ceased (partly because living donor surgeries aren't emergency surgeries, and were being cancelled with all elective surgeries as hospitals readied themselves for covid-19 patients, who materialized in large numbers in some places but not others). Deceased donor transplants have also been down, for a variety of corona-related reasons, which means that donor organs are going to waste.

Here's an aggregate graph from https://unos.org/covid/

And here's a story from Statnews.com

Transplants plummet as overwhelmed hospitals focus on the coronavirus
By ELIZABETH COONEY

"Organ transplant medicine is always a high-wire act, balancing too many people’s needs with too few matches. The coronavirus epidemic has only heightened the significant risks and hoped-for benefits of transplant surgery. Organ donations are down by a third and the health care system itself is in full-blown scarcity, triaging elective surgeries to some unknown future date so only emergency cases find their way into precious operating rooms and intensive care beds. As life-saving as they are, even many transplants are being put off.

"For people who need a transplant, their fate depends on the organ and how sick they are. Pancreas transplants are on hold indefinitely, classified as “life-enhancing,” not life-saving because patients can survive on insulin. Kidney patients who can continue to function on dialysis have been taken off waiting lists while still accruing waiting time for the day when non-urgent transplants resume. Heart patients who are not already in the hospital on mechanical heart-assist devices and who may be able to wait a few weeks will do so.
...
"Prospective transplant recipients can’t have Covid-19, either. The immune-suppression drugs they must take to prevent organ rejection would prevent them from fighting off the virus and make them super-shedders of the virus, placing those around them at hugely increased risk of being infected.

Transplant emergencies mean people who can’t wait another week or even another day. But these patients are also balancing on a knife’s edge: They have to be sick enough to be near death but well enough not to need long ICU stays in hospitals overwhelmed by coronavirus patients who need weeks on ventilators so they can breathe.

“Our ability to do a liver transplant is not always just about the [risk of Covid-19] exposure to the patient,” said David Mulligan, chief of transplantation surgery and immunology at Yale. “It’s also, do we have a bed? Do we have a ventilator to take care of the patient? Can we isolate the patient from other Covid-infected patients? Do we have enough time to do this operation, get them through it, keep them away from Covid, and then get them out of the hospital safely? That’s what we’re shooting for.”
...
"The widespread delays in testing people for the coronavirus have also meant delays in testing organs, said Gabriel Danovitch, medical director of UCLA’s kidney and pancreas transplant program. “When the virus was first detected, we didn’t have the capacity to test all potential donor organs. And a lot of organs were wasted because of concern of possible infection.”

Repugnance watch: Hungary moves to roll back legal recognition of transsexuality

The covid-19 pandemic has allowed a consolidation of authoritarian power in Hungary, as also elsewhere, which can take some odd forms.

The Guardian has the story:

Hungary prepares to end legal recognition of trans people
Trans people fear more discrimination as Orbán pushes through law defining gender based on ‘sex at birth’

"Hungary’s rightwing government looks likely to push through legislation that will end the legal recognition of trans people by defining gender as “biological sex based on primary sex characteristics and chromosomes” and thus making it impossible for people to legally change their gender.
...
"“In Hungary, you need to show your ID to rent a bike, buy a bus pass or to pick up a package at the post office. It basically means coming out as trans to complete strangers, all the time. The good version is they are nice about it, but there are situations where people turn quite hostile,” said Ivett Ördög, a 39-year-old trans woman living in Budapest."
*********

Here's the background story:
Hungary seeks to end legal recognition of trans people amid Covid-19 crisis

"The Council of Europe’s commissioner for human rights, Dunja Mijatović, called on Hungary’s parliament not to adopt the law, and said the measure was in contravention of human rights standards and the case law of the European court of human rights."

Test design and gender gaps in performance--evidence from a national exam in Chile, by Coffman and Klinowski

Here's a recent paper from PNAS:

The impact of penalties for wrong answers on the gender gap in test scores
Katherine B. Coffman and   David Klinowski
PNAS April 21, 2020 117 (16) 8794-8803;

Abstract:
Multiple-choice examinations play a critical role in university admissions across the world. A key question is whether imposing penalties for wrong answers on these examinations deters guessing from women more than men, disadvantaging female test-takers. We consider data from a large-scale, high-stakes policy change that removed penalties for wrong answers on the national college entry examination in Chile. The policy change reduced a large gender gap in questions skipped. It also narrowed gender gaps in performance, primarily among high-performing test-takers, and in the fields of math, social science, and chemistry.

Yelping about restaurant health violations, by Dai and Luca

Online reviews, like Yelp, can play an effective role in disseminating information about restaurant hygiene scores...

Digitizing Disclosure: The Case of Restaurant Hygiene Scores†
By Weijia Dai and Michael Luca*
American Economic Journal: Microeconomics 2020, 12(2): 41–59


Abstract: Collaborating with Yelp and the City of San Francisco, we revisit a canonical example of quality disclosure by evaluating and helping to redesign the posting of restaurant hygiene scores on Yelp.com. We implement a two-stage intervention that separately identifies consumer response to information disclosure and a disclosure design with improved salience—a consumer alert. We find score posting is effective, but improving salience further increases consumer response.

They write:

"The rise of online platforms raises the opportunity to revisit disclosure initiatives and to use a design economics lens to improve decisions about where and how disclosure is delivered.
...
"Our intervention proceeds in two stages. In the first stage, which begins in early 2013, Yelp starts posting hygiene scores on San Francisco restaurants. We analyze the impact of the score posting using a difference-in-differences strategy, comparing differential changes in restaurant demand after the score posting between restaurants with low hygiene scores that are more likely to be affected by the score posting (as predefined by the city) and those with higher scores.2  To shed light on demand,
we drew on purchase intention measures, such as a user calling or seeking directions to a restaurant or clicking on the restaurant’s own website link. We find that hygiene score posting on Yelp leads to a 13 percent decrease in purchase intentions for restaurants with low hygiene scores.
...
"Following the initial hygiene score posting intervention, in the second stage, we worked with Yelp in 2015 to develop a “hygiene alert”—a salient message that appears only on the Yelp pages of restaurants with low hygiene scores. Such low-score restaurants are identified by the city as having “poor” operating conditions with “high-risk” hygiene violations.

"We find a further 7 percent decrease in purchase intentions for restaurants with low scores due to hygiene alerts, and an 11 percent decrease in the number of reviews, nearly doubling the effect of the score posting for these businesses. On the restaurant side, although there is no evidence showing an improvement of restaurant hygiene scores across restaurants, we find suggested evidence of a decrease in the probability that the low-score restaurants will receive low scores again after the alert."

When supply chains break down, brokers make markets

During the Arab oil embargo of the U.S. in 1973, I remember hearing an oil broker discuss his day. He would cold call companies that used oil and ask if they had any to sell. Almost always he was told they were looking to buy oil, because their usual suppliers had gone dry. He'd write that down and go on to the next call.  Sometimes he'd find someone with oil to sell--maybe the general economic slowdown had reduced their consumption, but since they were normally buyers and not sellers they hadn't sold their surplus.  That kept the broker in business, he was able to help them sell their excess.

When well-established supply chains break down (e.g. as factories close in China and hospitals in NY are short of supplies, both because of the covid-19 pandemic), brokers are becoming important. Brokers work to piece together pieces of broken supply chains by connecting buyers and sellers. Even in times of shortages there can be sellers, with stock in their warehouses, who no longer have connection to buyers...

The NY Times has the story:

Marc Benioff’s $25 Million Blitz to Buy Protective Gear From China
A call from a university chancellor set in motion a private-sector effort to procure 50 million masks, gowns and swabs for American medical facilities.
By David Gelles

"The university’s usual suppliers in the United States were short on masks and face shields, and there was no sign that the State of California or the federal government was coming to the rescue. “The supply chain had really dried up,” Mr. Hawgood said.

"So Mr. Hawgood called Marc Benioff, the hyperconnected billionaire who is a founder and the chief executive of Salesforce.
...
"that phone call set off a frenzied effort by Mr. Benioff and his team that drew in major companies like FedEx, Walmart, Uber and Alibaba. In a matter of weeks, the team spent more than $25 million to procure more than 50 million pieces of protective equipment. Fifteen million units have already been delivered to hospitals, medical facilities and states, and more are on the way.

"The relative ease with which Salesforce acquired so much protective gear stands in sharp contrast to the often chaotic government efforts. While states have had to compete against one another for scarce supplies and the strategic national stockpile of protective gear is depleted, Mr. Benioff and his team simply called up their business partners in China and started writing checks.
...
"After Mr. Benioff got off the call with Mr. Hawgood on that Thursday, he called Daniel Zhang, chief executive of Alibaba, the enormous e-commerce marketplace. Last year, Salesforce and Alibaba announced a partnership meant to give Salesforce customers better access to the Chinese market, and teams from the two companies had been working closely.
...
"In San Francisco, Mr. Aytay and his team decided to buy only from companies that someone they knew well could personally vouch for. “Setting up a trust network was very important,” Mr. Aytay said.

"By March 22, the Salesforce team identified the first promising tip. The Jointown Pharmaceutical Group, a large Chinese company, had 500,000 surgical masks in a warehouse in Los Angeles."
*************

Of course there are perils in dealing with unusual suppliers, so the broker has to be reliable and have reliable connections.  After all, what could go wrong?

Buzzfeed news has the story:

After One Tweet To President Trump, This Man Got $69 Million From New York For Ventilators
The Silicon Valley engineer, who had no background in medical supplies but was recommended by the White House, never delivered the ventilators.

Hoarding and price gouging during Corona troubles

It appears we now have a Federal price gouging law.
Bloomberg has the story:

Accused New York Mask Hoarder Is First Charged Under Defense Act
By Patricia Hurtado

"In response to the Covid-19 pandemic, President Donald Trump on March 18 issued an executive order making it illegal to hoard medical supplies and devices which the U.S. has designated as scarce or sell them at excessive prices.
...
"Singh sold three-ply disposable face masks for $1 each, after having bought them for 7 cents -- a markup of about 1,328% -- Donoghue said, citing records seized from the store. Bulk sales were made to organizations serving vulnerable senior citizens and children battling the virus, according to the records.

"Singh “saw the devastating Covid-19 pandemic as an opportunity to make illegal profits on needed personal protective equipment,” said Craig Carpenito, the U.S. Attorney for the Eastern District of New Jersey who also heads the U.S. Department of Justice’s Covid-19 Hoarding and Price Gouging Task Force.

"U.S. postal inspectors seized 23 shipping pallets containing more than 100,000 face masks, 10,000 surgical gowns, 2,500 full-body isolation suits and more than 500,000 pairs of disposable gloves at Singh’s warehouse."
**********

And many states have had price gouging laws on the books for a long time. Here's a story from the WSJ:

Texas Attorney General Accuses Largest U.S. Egg Producer of Price-Gouging
Lawsuit alleges Cal-Maine Foods sold eggs at over 300% of their normal cost in coronavirus pandemic      By Rebecca Davis O’Brien

"The lawsuit shows the concern among law-enforcement officials and consumer-protection authorities over price-gouging on essential goods during the pandemic.
...
"Before the pandemic, between December 2019 and February 2020, Cal-Maine’s prices in Texas were around $1.02 for generic eggs and $1.89 for specialty eggs, according to the lawsuit.

"According to the lawsuit, as of 2015, Cal-Maine operated more than 90% of the largest egg-processing facilities in Texas. Nationally, Cal-Maine is the largest producer and marketer of shell eggs in the U.S., with a 19% overall market share, the lawsuit alleges, citing company statements.

"According to the lawsuit, Cal-Maine’s price jumps weren’t justified because its egg supply wasn’t affected—the company has said its facilities have been fully operational, with no disruptions to delivery or its supply chain. “During this pandemic, neither production costs nor contractual obligations forced Cal-Maine to charge exorbitant prices,” the lawsuit alleges.

"The lawsuit also alleges that Cal-Maine has misled the public about its egg prices, citing an April entry on the company website stating that “wholesale shell egg market prices…are outside of our control.” In fact, the attorney general alleges, there is no egg-market exchange, and Cal-Maine can exert control over prices."

AEA Awards: Clark Medal and Distinguished Fellows

Here's the AEA announcement:

2020 American Economic Association Awards
Congratulations to the 2020 John Bates Clark Medalist, Melissa Dell, and to the newly elected Distinguished Fellows: Katharine Abraham, Shelly Lundberg, Paul Milgrom, and Whitney Newey. View the Press Release for all award announcements.

Melissa Dell, Clark Medalist 2020

Distinguished Fellows
The Award of Distinguished Fellow was instituted in 1965. Past Presidents of the Association and Walker Medalists shall be Distinguished Fellows. Additional Distinguished Fellows may be elected, but not more than four in any one calendar year from economists of high distinction in the United States and Canada. The following economists have received this award:

2020

• Katharine Abraham
• Shelly Lundberg
• Paul Milgrom
• Whitney Newey