Sunday, February 4, 2018

Changing of the guard at Management Science (but papers on market design are solicited)

Here's an email announcement from Yan Chen and Axel Ockenfels about the recent change of editors at Management Science:

"We would like to update you on some recent development regarding behavioral economics at Management Science. As you may have heard, the new Editor-in-Chief, David Simchi-Levi, has decided to merge behavioral economics, judgment and decision making, and decision analysis into the newly expanded Decision Analysis Department (DA). The two of us will be the Department Editors handling behavioral economics papers within DA.

We have a terrific group of Associate Editors (AEs), including Al Roth and Richard Thaler who serve as our honorary AEs, and Björn Bartling (University of Zurich), Gary Bolton (University of Texas at Dallas), Peter Cramton (University of Cologne), Dan Friedman (University of California at Santa Cruz), Tanjim Hossain (University of Toronto), Scott Kominers (Harvard University), Dorothea Kübler (Berlin Social Science Center WZB), Katherine Milkman (University of Pennsylvania), Tanya Rosenblat (University of Michigan), Dirk Sliwka (University of Cologne), Matthias Sutter (Max Planck Institute for Research on Collective Goods, Bonn), and Stephanie W. Wang (University of Pittsburgh).

We hope that you will continue to submit your best papers to Management Science. Please
​​
, and note the new emphasis on (1) mechanism and market design at DA; and (2) relevance to the science and/or practice of management at the journal level.

In closing, we would like to thank Uri Gneezy and John List for bringing behavioral economics into Management Science. We hope to continue their excellent work and publish the best papers in our field.

Sincerely,
Yan ​​and Axel
--
Yan Chen

Saturday, February 3, 2018

Risks of living kidney donation: a meta-analysis

Better information is accumulating on the risks of living kidney donation. A meta-analysis has just been published January 30 in the Annals of Internal Medicine. It reports what the authors consider to be very moderately increased risk of kidney failure, and of pregnancy complications.

Mid- and Long-Term Health Risks in Living Kidney Donors
A Systematic Review and Meta-analysis
by Linda M. O’Keeffe, PhD*; Anna Ramond, DPharm*; Clare Oliver-Williams, PhD; Peter Willeit, MD; Ellie Paige, PhD;Patrick Trotter, MBChB; Jonathan Evans, MBChB; Jonas Wadstrom, MD; Michael Nicholson, MD; Dave Collett, PhD; and Emanuele Di Angelantonio, MD

From the Abstract:
"Although living kidney donation is associated with higher RRs  [relative risks] for ESRD and preeclampsia, the absolute risk for these outcomes remains low. Compared with nondonor populations, living kidney donors have no increased risk for other major chronic diseases, such as type 2 diabetes, or for adverse psycho-social outcomes."

And from the concluding discussion:
"Findings from this review may have implications for policies and practices related to living kidney donation. For example, donors should be informed that, although nephrectomy is associated with a higher RR for ESRD,the absolute risk is still low for most donors (that is, those not from known high-risk populations [39]). Thus, risk prediction tools for ESRD may better approximate the risks involved for prospective donors (43). Guidelines that do not contain information about pregnancy for living kidney donors should instead include relevant information for women of childbearing age in the informed consent process. Furthermore, this review supports the need for long-term follow-up of donors to monitor their health and mitigate possible increases in disease risks associated with kidney donation (44). In conclusion, compared with nondonor populations, living kidney donors have no increased risk for several major chronic diseases, with the exception of ESRD. However, the absolute risk for this disease remains low. Female donors who become pregnant after nephrectomy also seem to be at increased risk for preeclampsia, but more data are needed to confirm this finding."

Friday, February 2, 2018

San Francisco Will Clear Thousands of Marijuana Convictions

What happens when a formerly repugnant transaction goes from being illegal to being legal?
The NY Times has the story:
San Francisco Will Clear Thousands of Marijuana Convictions

"Thousands of people with misdemeanor convictions for marijuana possession dating back 40 years will have their criminal records cleared, the San Francisco district attorney’s office said Wednesday. San Diego is also forgiving old convictions.

"Recreational marijuana became legal in California this year, and the law allowed those with prior low-level offenses to petition for expungement, a process that can be costly.

"But in San Francisco and San Diego, people need not ask. George Gascón, San Francisco’s district attorney, said his office would automatically erase convictions there, which total about 3,000.

"An additional 4,900 felony marijuana charges will be examined by prosecutors to determine if they should be retroactively reduced to misdemeanors.

"San Diego has identified 4,700 cases, both felonies and misdemeanors, that will be cleared or downgraded."
***********

See my earlier posts on Turing's Law, named for Britain's 2003 posthumous pardon of Alan Turing who had been convicted of a crime when homosexual acts were illegal.

Thursday, February 1, 2018

Colleges that get a lot of applications read each one quickly (WSJ)

How to deal with congestion?  Move fast...  Here's the story from the WSJ:

Some Elite Colleges Review an Application in 8 Minutes (or Less)
With so many applying, fewer schools have one person read a whole application; plowing through 500 files in a day

"As application numbers surge, admissions officers at some elite colleges say they don’t have time to read an entire file.

"Instead, staffers from more schools—including the Georgia Institute of Technology, Rice University and Bucknell University in Pennsylvania—now divvy up individual applications. One person might review transcripts, test scores and counselor recommendations, while the other handles extracurricular activities and essays.

"They read through their portions simultaneously, discuss their impressions about a candidate’s qualifications, flag some for admission or rejection, and move on. While their decision isn’t always final, in many cases theirs are the last eyes to look at the application itself.

"The entire process can take less than eight minutes.
...
"Efficiency is crucial, since more students are using the Common Application, which allows them to submit material to multiple schools. Nearly 902,000 students used it last year. As of Jan. 15 this year, the number was already 898,000 students submitting to an average of 4.8 schools.

"Applications to Georgia Tech jumped by 13% for the coming academic year, to 35,600. The current freshman class has roughly 2,800 students."


Wednesday, January 31, 2018

Drug trafficking via the U.S. mail

A recent Senate report (which I haven't seen) has generated a lot of news coverage to the effect that fentanyl, a Schedule II controlled substance (i.e. a drug that may not be legally sold without a prescription in the U.S.) that is implicated in the current opioid crisis in the U.S., is widely available from internet sites that will send it to you in the mail.

Here's the WSJ story:

Stamp Out Easy Mail Access to Deadly Fentanyl, Senate Report Urges


"A U.S. Senate report raises fresh concerns about how easy it is to buy illicit, mail-order opioids from China, a source federal authorities say has fueled a nationwide addiction crisis claiming tens of thousands of lives.
The new Senate report, issued ahead of a hearing Thursday, is the latest to focus on how international mail has become a major conduit for these drugs.
Investigators for the Senate’s Permanent Subcommittee on Investigations posed as would-be online buyers, entering terms like “fentanyl for sale” into Google..."
***********

Tuesday, January 30, 2018

Science talent search finalists (and some alumni)

The  Regeneron Science Talent Search, which was sponsored by Westinghouse when I was in high school, has announced  its finalists this year, who compete for college scholarships by submitting the results of their scientific investigations.

Here's the story from CNN:
Could these students provide the science breakthroughs of the future?


I participated when I was in high school, but without progressing very far in the competition.

There are more science competitions for high school students than there used to be. I already blogged about one of the finalists (you can find them all here):

Komo, Andrew
Montgomery Blair High School, Silver Spring, Maryland
Cryptographically Secure Proxy Bidding in Ascending Clock Auctions

He came in first in another competition:

Saturday, December 23, 2017

Monday, January 29, 2018

Italy recommends Global Kidney Exchange to the World Health Organization

Global Kidney Exchange (GKE) was presented last week  in the executive session of the World Health Organization (WHO), the UN agency concerned with public health policy.   

Among the Statements submitted by Member States and other participants of the 142th session of the Executive Board  was this Statement from Italywhich encourages the WHO to include  in the 2019-2023 program the development of kidney transplantation  in low and middle income countries through cooperation, assistance and GKE, and proposes that the WHO should consider and implement a pilot project GKE program.  

  Here's the statement in full (points 6-10 are the action items):

Statement from Italy
Italy fully aligns with the statement carried out by Malta on behalf of European Union and its Member States.

Italy commends the DG and the Secretariat for the refined version of the Draft General Programme.

In particular Italy appreciates the additional attention given to migrants’ health in the new version of the programme of work.

In this session we would like to echo Spain’s remark and raise the EB and Member States’ attention to the problem of kidney transplantation globally.

In the past and in the current draft programme considerable attention has been correctly paid by WHO to TB, HIV and malaria,

However:

1. According to reliable international data, 2-7 million people die annually from kidney failure - more than from TB, HIV, and malaria combined. Transplantation is by far the most cost-effective treatment for kidney failure, particularly in low/middle income countries (LMIC)
2. Non-communicable diseases such as heart disease, diabetes, and kidney disease have replaced communicable diseases as the most common causes of premature death worldwide. An estimated 80% of this burden occurs in LMIC.
3. Billions of dollars are spent in LMIC to reduce the burden of communicable diseases, but significantly less is spent on non-communicable diseases. Consequently, the gap in healthcare between High Income Countries (HIC) and LMIC has become particularly large for noncommunicable diseases such as kidney failure.
4. Transplantation is preferable to dialysis as a treatment for kidney failure. Transplant patients live on average 10 years longer, and have better quality of life than those on dialysis. In some LMIC, as many as 75% of patients who start dialysis die within one year. Moreover, transplantation is much less expensive than dialysis over time. This is very much limited by the limited availability of organs that can be addressed with kidney exchange.
5. Kidney exchange extends the reach of living donation because some healthy living donors are not able to give a kidney to a loved one for reasons outside of their control. However, they could exchange their kidney with another such pair so that both patients are able to receive a living donor kidney transplant. Kidney exchange is practiced routinely in HIC and preliminary clinical experience indicates it could be expanded globally to increase access to living donor kidney
transplantation. Kidney exchange is equitable, mutually beneficial, and has been carefully developed to be ethical, legal, and transparent.
6. We encourage WHO to include organs and in particular kidney transplantation in its programme as we believe that oversight, cooperation and assistance of the WHO to carry out a pilot program with strong international governance that is consistent with the highest ethical and legal standards, and that carefully approves participating countries, facilities, healthcare providers, and patient-donor pairs should be conceived and implemented.
7. Given that transplantation is more cost effective than dialysis, the savings attained in HIC from transplantation affords LMIC patients the opportunity to participate in kidney exchanges with HIC patients. We refer to this as Global Kidney Exchange (GKE).
8. Consider the figure: the LMIC mother wishes to donate to her daughter, and the HIC brother wishes to donate to his sister, but neither pair is able to proceed. Without transplantation, the LMIC daughter will die and the HIC sister will remain on dialysis. However, through GKE each patient receives a compatible kidney from the other patient’s donor. Furthermore, the savings attained in the HIC can also support long-term care of the LMIC donor and recipient in their home country.
9. Preliminary clinical experience in a small sample of exchanges between LMIC and HIC pairs has achieved 100% patient and graft survival as well as donor safety with up to 3 years of follow-up.
10. The pilot program would establish a technical working group to develop a self-sustaining and scalable GKE program that will:
a. Execute planning meetings to carefully develop the criteria for participating countries, physicians and patient-donor pairs;
b. Design, create, and implement an international governance protocol; and
c. Perform and test Global Kidney Exchanges.


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

Here's a link to the whole meeting:

142nd session of the WHO Executive Board

22 January 2018 – This week the WHO Executive Board is setting the agenda for the World Health Assembly, and determining how to best promote health, keep the world safe, and serve the vulnerable. The session takes place on
22–27 January 2018 in Geneva, Switzerland.

Update: you can watch the Italian representative, Professor Walter Ricciardi, deliver the statement  in the live webcast, afternoon session part 2 (in the links on the right), at minute 57 for about 3 minutes.
********************
Here are all my posts on GKE, which tell of its clinical success so far, and of some highly politicized opposition that it attracted. However as transplant professionals have had an opportunity to hear directly about the proposal, calmer, more practical discussions are taking place, and GKE is gaining support.  This most recent recommendation from Italy to the WHO seems like a responsible way to move forward.

I support the call for action in point 10 of the Statement of Italy, and I think that the need to establish careful rules around the issues included in point 6 are well considered. I'm cautiously optimistic that this will mark a turning point towards practical, evidence-based exploration of ways to extend the very considerable benefits of kidney exchange, transparently, ethically, and without undue delay.
*********

(Here are some pictures from our meeting in Rome, two weeks ago...)

Sunday, January 28, 2018

How banks support payday lenders and check cashing services by dissing their low income customers

Here's a story from the WSJ that I found disturbing (and which helps explain why many people choose to be "unbanked" and to patronize high-priced non-bank financial services):

Bank of America: No More Free Checking for Customers With Low Balances
eBanking customers switched into accounts that typically require direct deposit or a minimum balance to avoid $12 monthly fee

"Bank of America Corp. has eliminated a free checking account popular with some lower-income customers, requiring them to keep more money at the bank to avoid a monthly fee.

"This month, all remaining eBanking customers with the Charlotte, N.C., lender were switched into accounts that charge a $12 monthly fee unless the customer has a direct deposit of $250 or more or a minimum daily balance of $1,500. Some eBanking customers were switched over as early as 2015.

"Banks have long grappled with how to charge customers for basic checking services. The accounts are costly for banks to maintain, though they do bring in revenue through overdraft and other fees."
**************

Some previous posts about the other part of this market:

Friday, November 3, 2017

Thursday, January 22, 2015


Saturday, January 27, 2018

2018 Tsinghua Conference on Behavioral, Experimental and Theoretical Economics (Tsinghua BEAT)

Here's the call for papers with a Feb 1 deadline:

Call for Papers : Tsinghua BEAT 2018

Dear Colleagues, 

We are pleased to announce the call for papers for the 2018 Tsinghua Conference on Behavioral, Experimental and Theoretical Economics (shortened as Tsinghua BEAT). The conference will be held on the campus of Tsinghua University, at the School of Economics and Management, in Beijing on July 9-10, 2018

Plenary speakers at Tsinghua BEAT include:

Jacob Goeree, University of New South Wales; 
Ed Hopkins, University of Edinburgh; 
Muriel Niederle, Stanford University; 
Alvin Roth, Stanford University. 

The conference has a single track. Please consider submitting a paper in the areas of behavioral, experimental and theoretical economics to the conference by February 1, 2018. Papers should be sent as email attachments to tsinghua.beat@gmail.com, with the subject line: [2018 Tsinghua BEAT submission]. Extended abstracts will not be accepted. Members of the organizing committee will put together the program and notify the participants by March 1, 2018. The acceptance rate for submitted papers for the 2017 conference was 50%. We look forward to welcoming you in July at Tsinghua. 

Sincerely,
Chong-En Bai 
Yan Chen 
Ming Gao 
Audrey Hu 
Tracy Xiao Liu 
Alex White 
Jie Zheng 
Xiaohan Zhong 

Programs from Previous Years:

Link to Conference Website:

Friday, January 26, 2018

Vermont legalizes marijuana

The Washington Post has the story:

Vermont is the first state to legalize marijuana through legislature

"Gov. Phil Scott (R) signed a bill Monday legalizing marijuana for adults over 21. It allows for the possession of an ounce or less of marijuana, two mature and four immature plants. Vermont is the ninth state to legalize recreational marijuana for adults. The other states did so through ballot initiatives.

"But Vermont’s law is notable for what it does not do: create a state marketplace for the sale of marijuana.

Instead, it directs a marijuana advisory board to study what a legal marketplace where marijuana is taxed and regulated would look like in Vermont and report to the governor by Dec. 15.
...
"The measure creates a number of new marijuana laws, including stronger penalties for selling marijuana to people under 21 or enabling their consumption of the drug and makes it a crime to use marijuana in a vehicle where there is a child. It also makes the consumption of marijuana in public illegal.

"Scott said the commission must create education campaigns around marijuana and ways to keep the state’s roads safe.

“To be very direct: There must be comprehensive and convincing plans completed in these areas before I will begin to consider the wisdom of implementing a commercial ‘tax and regulate’ system for an adult marijuana market,” Scott wrote.

The law will take effect in July."

Thursday, January 25, 2018

Legal marijuana and crime reduction

The Guardian channels an academic paper from the EJ:

Here's the Guardian story:
Legal marijuana cuts violence says US study, as medical-use laws see crime fall
Murder and violent crime found to have decreased most in states bordering Mexico as drug cartels lose business to regulation

And here's the paper:
Evelina Gavrilova
Takuma Kamada
Floris Zoutman 
Forthcoming in Economic Journal 

Abstract: We examine the effects of medical marijuana laws (MMLs) on crime. We exploit theintroduction of MMLs as quasi-experimental variation. Using data from the UniformCrime Reports, we show that the introduction of MMLs lead to a decrease of 12.5 percentin violent crime, such as homicides, aggravated assaults and robberies in states that borderMexico. We also show that the reduction in violent crimes is strongest for counties closeto the border (less than 350km), while there is no significant impact of MMLs on crimefor counties located further inland. Analysis from the Supplementary Homicide Reportsdata reveals that the decrease in homicides can largely be attributed to a drop in drug-lawrelated homicides. We find evidence for spillover effects. When an inland state passesa MML, this results in a decrease in crime in the nearest border state. Our results areconsistent with the theory that the introduction of MMLs reduces activity by Mexicandrug trafficking organizations and their affiliated gangs in the border region. MMLs exposedrug trafficking organizations (DTOs) to legitimate competition, and substantially reducetheir profits in one of their most lucrative drug markets. This leads to a decrease in drug-related crime in the Mexican border area. Our results indicate that decriminalization ofthe production and distribution of drugs may lead to a reduction in violence in marketswhere organized drug criminals meet licit competition.

Wednesday, January 24, 2018

Ninth Circuit rules that laws against prostitution are not unconstitutional

The Washington Post has the best headline:
They argued that prostitution is a constitutional right. Nice try, said federal court.

"The Supreme Court’s 2003 ruling in the case Lawrence v. Texas is one of its best-known in recent memory. In a 6-3 decision, the justices invalidated every remaining sodomy law in the United States, rendering the country’s archaic and largely unenforced bans on same-sex sexual activity unconstitutional. “Intimate conduct” between consenting adults was a fundamental right protected by the Constitution’s due process clauses, the high court found.
...
"The Erotic Service Provider Legal Education and Research Project, or ESPLERP, filed a lawsuit in federal court in 2015 claiming that, under the Supreme Court’s ruling, California’s anti-prostitution law violates the constitutional rights of prostitutes and clients to engage in consensual sexual activity. They even went so far as to say that the ruling barred laws criminalizing prostitution among adults and that paying for sex was a form of protected commercial speech.
...
"On Wednesday, the San Francisco-based court threw out the lawsuit, ruling that paying for sex didn’t count as the type of “intimate conduct” that Supreme Court justices had in mind.

“There is no constitutional rights to engage in illegal employment, namely, prostitution,” Judge Jane A. Restani wrote for the three-judge panel."
**********

Here's the story in the SF Chronicle:
Sex for sale is not a constitutional right, court rules

"Three former prostitutes, a would-be client and the Erotic Service Providers Legal, Educational and Research Project had argued that the high court, in striking down state laws against gay or lesbian sexual activity, recognized an adult’s right to engage in consensual sex without state interference. They maintained that the ruling extended to adults who consent to sex for a price.

"A panel of the Ninth U.S. Circuit Court of Appeals in San Francisco seemed receptive to that argument at a hearing in October, suggesting that the 1872 state ban might need closer scrutiny.

"One panel member said prostitution had been historically subjected to the same sort of moral disapproval that had once condemned gay sex, and might be more acceptable under the Supreme Court’s current view of individual rights. Another asked why it should be “illegal to sell something that it’s legal to give away.

"But in a 3-0 ruling Wednesday, the panel ruled that the Supreme Court had not legalized prostitution with its 2003 decision.

"Although the scope of the ruling was not clear, the Supreme Court specified that the gay sex case “does not involve ... prostitution,” Jane Restani, a judge of the U.S. Court of International Trade temporarily assigned to the appeals court, wrote in the panel’s decision."

Tuesday, January 23, 2018

Peter Singer on the undersupply of opiods in the developing world

There's been a lot of discussion of the oversupply of opioids in the U.S.  Here's a discussion of the undersupply in the developing world.
Prisoners of Pain

"Whereas the quantity of available opioids in the United States is more than three times what patients in need of palliative care require, in India, the supply is just 4% of the required quantity, and just 0.2% in Nigeria. The reason is a misplaced fear that clinical use of opioids will fuel addiction and crime in the community.

He refers us to the Lancet report;
Alleviating the access abyss in palliative care and pain relief—an imperative of universal health coverage: the Lancet Commission report

"Executive Summary
The lack of global access to pain relief and palliative care throughout the life cycle constitutes a global crisis, and action to close this divide between rich and poor is a moral, health, and ethical imperative. The need for palliative care and pain relief has been largely ignored. Yet, palliative care and pain relief are essential elements of universal health coverage (UHC).

This Lancet Commission aims to (1) quantify the heavy burden of serious health-related suffering associated with a need for palliative care and pain relief; (2) identify and cost an essential package of palliative care and pain relief health services that would alleviate this burden; (3) measure the unmet need of an indispensable component of the package—off patent, oral, and injectable morphine; and (4) outline national and global health-systems strategies to expand access to palliative care and pain relief as an integral component of UHC while minimising the risk of diversion and non-medical use."

Monday, January 22, 2018

Pursuing Global Kidney Exchange in Rome: photos

I was recently in Rome, where a substantial group gathered (see below) to further the possibilities of Global Kidney Exchange (GKE). Part of our efforts were focused on presentations to a January 15-16 Meeting of the EU Competent Authorities on Organ Donation and Transplantation, Co-Chaired by the European Commission..

You can see a photo of Mike Rees beginning his talk, with the names of various co-conspirators.
Finally, there's good coffee in Rome. I recommend the famously good Sant Eustachio.





So far, the EU competent authorities haven't issued any statement.

Sunday, January 21, 2018

The number of organ donors in Germany has fallen to its lowest level in 20 years.

Rosemarie Nagel draws my attention to this article in Der Spiegel on transplantation in Germany:



Transplantation
Wieso werden in Deutschland so wenige Organe gespendet?
Die Zahl der Organspender in Deutschland ist auf den niedrigsten Stand seit 20 Jahren gesunken. Woran liegt das? Und wie kann man einer Spende zustimmen - oder sie ablehnen? Der Überblick.

Google translate renders it as: Transplantation
Why are donated so few institutions in Germany?
The number of organ donors in Germany has fallen to its lowest level in 20 years. Why is that? And how can you agree to a donation - or reject it? The overview.

Friday, January 19, 2018

Bob Wilson, Paul Milgrom and Dave Kreps win the Carty Award



Game theory at Stanford:)


Here's the press release from the National Academy of Science

David M. Kreps, Stanford University Graduate School of Business, Paul R. Milgrom, Stanford University Department of Economics, and Robert B. Wilson, Stanford University Graduate School of Business, will receive the 2018 John J. Carty Award for the Advancement of Science.


"Kreps and Wilson provided a framework, known as sequential equilibrium, for modeling dynamic effects in economics. All three of the award winners, together with other collaborators and in particular D. John Roberts, employed these techniques to model and study reputation and collusion, both of which have broad applications in macroeconomics, industrial organization, and labor economics.
Later, the entire modern telecommunications industry arose out of an auction format developed by Milgrom and Wilson, along with Preston McAfee, for the 1994 radio spectrum auctions by the Federal Communications Commission. The simultaneous ascending auction format, in which each bidder can bid for multiple licenses over a series of rounds so long as it remains “sufficiently active,” has since been used around the world to allocate hundreds of billions of dollars’ worth of wireless licenses. Variations of the format have also been applied to numerous other industries, including electricity markets and various commodity markets.  
The three award winners, with collaborators and alone, have contributed broadly to other topics in economics: Kreps has done foundational work in choice theory and financial market theory; Milgrom, in the theories of market microstructure and the principal-agent problem; and Wilson, in nonlinear pricing and utility regulation, as well as the foundations of dynamic equilibria.
The John J. Carty Award for the Advancement of Science is awarded every two years, to recognize noteworthy and distinguished accomplishments. In 2018 the award is presented in the field of economics. The award is presented with a medal and a $25,000 prize."

Thursday, January 18, 2018

Evolution of dating apps: OK Cupid requires mutual consent for messaging

Slate reports (last month):
OkCupid Users Have Long Had to Put Up With Unwanted Messages. That's About to Change
"OkCupid announced a big change to its messaging system in an email to users on Friday afternoon. Starting next week, the email said, “Only the people you like or have responded to will remain in your messages. Messages from people you're not interested in, or people you haven't liked yet, will be moved to their profile.”
"This shift will bring the platform more in line with other online dating platforms, such as Tinder and Bumble, on which users can’t message one another at all until both have shown interest in the other. The new OkCupid way won’t be quite so strict—users can still send messages to whomever they want, though those messages will only appear in the recipients’ mailboxes if they indicate that they like the sender—but engineers hope it will help seed more connections while filtering out some messages that will never get a response."

Wednesday, January 17, 2018

Analytic approaches to allocating organs for transplants

Two recent items:

Adapting a Kidney Exchange Algorithm to Align with Human Values
by Rachel Freedman, Jana Schaich Borg, Walter Sinnott-Armstrong, John P. Dickerson, Vincent Conitzer

Abstract:
The  efficient  allocation  of  limited  resources  is  a  classical problem in economics and computer science. In kidney exchanges,  a  central  market  maker  allocates  living  kidney donors to patients in need of an organ. Patients and donors in kidney exchanges are prioritized using ad-hoc weights decided on by committee and then fed into an allocation algorithm that determines who get what—and who does not. In this paper, we provide an end-to-end methodology for estimating weights of individual participant profiles in a kidney exchange.  We first elicit from human subjects a list of patient attributes they consider acceptable for the purpose of prioritizing patients (e.g., medical characteristics, lifestyle choices,and  so  on).  Then,  we  ask  subjects  comparison  queries between  patient  profiles  and  estimate  weights  in  a  principled way from their responses. We show how to use these weights in kidney exchange market clearing algorithms. We then evaluate the impact of the weights in simulations and find that the precise numerical values of the weights we computed matter little, other than the ordering of profiles that they imply.However, compared to not prioritizing patients at all, there is a significant effect, with certain classes of patients being (de)prioritized based on the human-elicited value judgments.
**************

And

How analytics and machine learning can aid organ transplant decisions
by Dimitris Bertsimas and Nikolaos Trichakis

"MIT Sloan and Massachusetts General Hospital have developed an analytics tool to help doctors in deceased-kidney acceptance decisions. The model aims to calculate the probability of a patient being offered a deceased-donor kidney of a certain quality level within a specific time frame (three, six, or 12 months), given their individual characteristics. Using machine learning, it looks at 10 years of data and millions of prior decisions to estimate a patient’s waiting time in the context of a current active organ offer until the time to the next offer for a higher quality kidney."

Tuesday, January 16, 2018

Welfare effects of limiting the number of interviews by Beyhaghi and Tardos

Here's a new paper on a subject that is coming up in a number of the markets that I keep an eye on:

Effect of Limited Number of Interviews onMatching Markets
by Hedyeh Beyhaghi and Eva Tardos

Abstract. We study outcome of two-sided matching between prospective medical residents who can only apply to a limited number of positions and hospitals who can interview only a limited number of applicants and show non-intuitive effects in the matching outcomes. We study matching size as our notion of efficiency, and show when the number of interviews is limited, a market with limited number of applications achieves a higher efficiency compared to a market with no limit. Also we find that a system of treating all applicants equally (setting the same limit for their number of applications), is more efficient rather than allowing a small set to apply to one more/less position. This comparison results in a scallop-shape figure 2 that shows expected size of matching with respect to expected number of applications. Finally we show that limiting number of interviews does not always hurt efficiency of matching markets and can improve social welfare in certain cases.