Monday, January 24, 2022

23rd ACM Conference on Economics and Computation (EC’22)--call for papers (by Feb 10)

 The deadline is 11:59pm EDT on Feb 10, but I'm guessing that papers have a good chance of being received as late as midnight.

23rd ACM Conference on Economics and Computation (EC’22): Call for Contributions

"TL;DR for Seasoned Authors:

Papers submitted to EC’22 must select one of four methodological tracks and up to two content areas. The list of tracks and content areas can be found below.

EC’22 is continuing the forward-to-journal option as in previous years.

EC’22 is currently planned as a primarily in-person event, with some components (e.g., poster sessions and tutorials) to be held either virtually or in a hybrid format. Presenters of accepted papers who cannot (or do not feel comfortable to) travel to EC’22 will have the option to present their paper virtually.


Timetable for Authors

February 10, 2022 (11:59 pm EST): Paper submission deadline

April 11, 2022 (11:59pm EDT): Reviews sent to authors for feedback

April 14, 2022 (11:59pm EDT): Author responses due

May 8, 2022: Paper accept/reject notifications

May 18, 2022 (11:59pm EDT): Camera-ready versions of accepted papers due

July 11-15, 2022: Conference technical program"


Program Chairs:

Sven Seuken (University of Zurich and ETH AI Center)

Ilya Segal (Stanford University)

Contact the PC chairs at 

Track Chairs:

Theory: Robert Kleinberg (Cornell University) and Aaron Roth (University of Pennsylvania)

Applied Modeling: Gabriel Weintraub (Stanford University)

Empirics: Georgios Zervas (Boston University)

AI: Kevin Leyton-Brown (University of British Columbia)

EC’22 will use the following areas:

Mechanism design

Auctions and pricing

Market design and matching markets

Contract design

Online platforms and applications

Econometrics, ML, and data science

Equilibria, learning, and dynamics in games

Social choice and voting theory

Social networks and social learning

Fair division

Market equilibria

Crowdsourcing and information elicitation

Privacy, algorithmic fairness, social good, and ethics

Blockchain and cryptocurrencies

Behavioral economics and bounded rationality

Area Chairs: Nick Arnosti (University of Minnesota)  Haris Aziz (University of New South Wales)  Moshe Babaioff (Microsoft Research)  Yakov Babichenko (Technion)  Bruno Biais (Toulouse School of Economics)  Martin Bichler (Technical University of Munich)  Larry Blume (Cornell University)  Liad Blumrosen (Hebrew University)  Benjamin Brooks (University of Chicago) Yang Cai (Yale University)  Agostino Capponi (Columbia University)  Yeon-Koo Che (Columbia University)  Rachel Cummings (Columbia University)  Nikhil Devanur (Amazon)  John Dickerson (University of Maryland)  Laura Doval (Columbia University)  Paul Duetting (Google Research)  Michal Feldman (Tel Aviv University)  Ashish Goel (Stanford University)  Hanna Halaburda (New York University Stern School of Business)  Hoda Heidari (Carnegie Mellon University)  Martin Hoefer (Goethe University Frankfurt)  Ian Kash (University of Illinois at Chicago)  Fuhito Kojima (University of Tokyo)  Nicolas Lambert (MIT)  Jacob Leshno (The University of Chicago Booth School of Business)  Shengwu Li (Harvard University)  Annie Liang (University of Pennsylvania)  Brendan Lucier (Microsoft Research)  Mohammad Mahdian (Google Research)  Azarakhsh Malekian (University of Toronto)  R. Preston McAfee  Reshef Meir (Technion)  Jamie Morgenstern (University of Washington)  Thayer Morril (North Carolina State University)  Denis Nekipelov (University of Virginia)  Sigal Oren (Ben-Gurion University)  Michael Ostrovsky (Stanford University)  Rafael Pass (Cornell University)  Ariel Procaccia (Harvard University)  Marek Pycia (University of Zurich)  Marzena Rostek (University of Wisconsin-Madison)  Jay Sethuraman (Columbia University)  Nisarg Shah (University of Toronto)  Peng Shi (University of Southern California)  Alex Slivkins (Microsoft Research)  Eric Sodomka  Nicolas Stier-Moses (Facebook)  Siddharth Suri (Microsoft Research)  Steve Tadelis (Berkeley–Haas)  Inbal Talgam-Cohen (Technion)  Alexander Teytelboym (University of Oxford)  Utku Unver (Boston College)  Vijay Vazirani (University of California, Irvine)  Jens Witkowski (Frankfurt School of Finance & Management)  James Wright (University of Alberta)  Lirong Xia (Rensselaer Polytechnic Institute)  Bumin Yenmez (Boston College)  Yair Zick (University of Massachusetts, Amherst)  Aviv Zohar (The Hebrew University of Jerusalem)

Sunday, January 23, 2022

Paired kidney donation performed in Germany--a guest post by Ágnes Cseh

 Below is a post written by Ágnes Cseh, about a kidney exchange conducted legally in Germany, in October, after being identified outside of the medical establishment. (The links she supplies are all worth looking into, and Google translate works well enough.)

"The legal basis for a living organ donation in Germany is a relationship or close personal connection between donor and recipient. This well-meant rule implicitly forbids paired kidney donation, because even though recipient and donor are closely related in each of the two pairs participating in a paired donation, the physical graft a patient receives technically comes from the relative of the other recipient.

A cumbersome, but legal way around the regulation is to establish a close personal connection between all four persons involved in a paired donation. Then, an ethical committee might approve of the two transplants separately. This constellation even inspired filmmakers to shoot a fictional movie about such a venture -- the genre is supposed to be comedy. In reality, paired transplants have been performed very sporadically in the past years in Germany.

A new initiative offers a centralized platform for paired kidney donations. It is run by Susanne Reitmaier, an activist fighting for the complete legalization of paired donations and Ágnes Cseh, a researcher specialized in matching theory. They maintain a database of the voluntarily submitted medical data of incompatible recipient-donor pairs. If a possible match among these pairs is found, then the two pairs are put into contact with each other so that they can establish the personal connection required by the law.

The first match in this program was identified in July 2020. After a long journey (see the detailed report in English here and in German here), the transplants were finally performed in October 2021 in Berlin. The ethical committee first rejected their claim, but then approved of the two transplants as one paired donation, not as two separate donations. This might be a milestone in the practice and potentially lead to more standardized procedures in the future.

As time goes by and word gets around, more and more incompatible pairs enter their data into the database. A handful of already identified pairs for paired donations are currently in different stages of the medical and legal process. The first step taken by Charité Berlin encouraged other hospitals to show interest in conducting paired transplants.

Despite of this recent progress, an efficient kidney exchange program would clearly require a law change in Germany. It would be sufficient to modify the current regulation marginally, by stating that the close personal connection is meant for the pairs entering the pool together and not for the matched pairs."


Here's a link to (and translation of) an op-ed I published in a German newspaper in 2016 urging that the law be amended to allow regular kidney exchange:

German organ transplant law should be amended or reinterpreted to allow kidney exchange: my op-ed in Der Tagesspiegel

And here are all my posts on kidney exchange in Germany.

Saturday, January 22, 2022

Matchup 2022: matching and market design in Vienna, August 25-2

 Here's the announcement and call for papers

Matchup 2022 

MATCH-UP 2022 is the 6th workshop in an interdisciplinary and international workshop series on matching under preferences . It will take place on 25-26 August 2022, hosted by TU Vienna and co-located with MFCS 2022 (47th International Symposium on Mathematical Foundations of Computer Science).

Matching problems with preferences occur in widespread applications such as the assignment of school-leavers to universities, junior doctors to hospitals, students to campus housing, children to schools, kidney transplant patients to donors and so on. The common thread is that individuals have preferences over the possible outcomes and the task is to find a matching of the participants that is in some sense optimal with respect to these preferences. There has been a resurgence of activity in this area in recent years, with online and mobile computing opening up new avenues of research and novel, path-breaking applications.

The remit of this workshop is to explore matching problems with preferences from the perspective of algorithms and complexity, discrete mathematics, combinatorial optimization, game theory, mechanism design, and economics. Thus, a key objective is to bring together the research communities of the related areas. Another important aim is to convey the excitement of recent research and new application areas, exposing participants to new ideas, new techniques, and new problems.

List of Topics

The matching problems under consideration include, but are not limited to:

  • Two-sided matchings involving agents on both sides (e.g., college admissions, medical resident allocation, job markets, and school choice)

  • Two-sided matchings involving agents and objects (e.g., house allocation, course allocation, project allocation, assigning papers to reviewers, and school choice)

  • One-sided matchings (e.g., roommate problems, coalition formation games, and kidney exchange)

  • Multi-dimensional matchings (e.g., 3D stable matching problems)

  • Matching with payments (e.g., assignment game)

  • Online and stochastic matching models (e.g., Google Ads, ride sharing,

  • Other recent applications (e.g., refugee resettlement, food banks, social housing, and daycare)

Invited Speakers

Friday, January 21, 2022

Black market marijuana coexists with legal marijuana in Oregon, and competes with it in California

In a growing number of U.S. states, it is legal to grow and sell marijuana. But the price remains highest in the states where it is illegal, and so black markets persist alongside legal markets. 

Politico has the story:

‘Talk About Clusterf---’: Why Legal Weed Didn’t Kill Oregon’s Black Market. Legalization was supposed to take care of the black market. It hasn’t worked out that way.  By NATALIE FERTIG

"Over the last two years, there’s been such an influx of outlaw farmers that southern Oregon now rivals California’s notorious Emerald Triangle as a national center of illegal weed cultivation. Even though marijuana cultivation has been legal in Oregon since 2014, Jackson County Sheriff Nate Sickler says there could be up to 1,000 illegal operations in a region of more than 4,000 square miles. The Oregon Liquor and Cannabis Commission, which oversees the state’s $1.2 billion legal cannabis industry, estimates the number of illicit operations is double that.


"What is happening in the woods of the southern Oregon represents one of the most confounding paradoxes of the legalized marijuana movement: States with some of the largest legal markets are also dealing with rampant illegal production — and the problem is getting worse. Oklahoma, where licenses to cultivate medical marijuana are some of the easiest to get in the nation, has conducted more than five dozen raids on illicit grows since last April. In California, meanwhile, most of the state continues to purchase cannabis from unlicensed sources — straining legal operators already struggling with the state’s high taxes and fees.


"One of the underlying promises for legalizing cannabis was that legalization would make the illegal drug trade, with all its attendant problems of violent crime and money laundering, disappear. But 25 years into the legalization movement, as 36 states have adopted some form of legalized marijuana, the black market is booming across the country. Legal states such as Oregon and California — which have been supplying the nation for nigh on 60 years — are still furnishing the majority of America’s illegal weed.


"Oregon’s weed is some of the cheapest in the nation, and Oregonians predominantly purchase weed from licensed dispensaries. Economist Beau Whitney estimates that 80-85 percent of the state’s demand is met by the legal market. But most of the illicit weed grown in southern Oregon is leaving the state, heading to places where legal weed is still not available for purchase such as New York or Pennsylvania — or where the legal price is still very high, like Chicago and Los Angeles. In Illinois, which legalized medical marijuana in 2013, only about a third of the demand for cannabis is satisfied by legal dispensaries, according to Whitney. Differences in tax rate and regulations plays the major role in differences from state to state, Whitney explains.


And in California it appears that high taxes on the legal market allow the black market to exist alongside. NBC has the story:

Craft cannabis industry in California is 'on the brink of collapse,' advocates say. Small cannabis growers and operators say the state's hefty taxes are shutting them out despite promises to expand the industry and make it more inclusive.  By Alicia Victoria Lozano

"Last month, marijuana companies warned Newsom in a letter that immediate tax cuts and a rapid expansion of retail outlets were needed to steady an increasingly unstable marketplace shaken by illicit dealers and growers.

"More than two dozen cannabis executives and legalization advocates signed the letter after years of complaints that the heavily taxed industry is unable to compete with the widespread illegal economy, which offers far lower consumer prices and has double or triple the sales of the legal market."

Thursday, January 20, 2022

Vacancy chains in urban housing

 Vacancy chains occur not just in labor markets, but also in housing markets. (Earlier this week I wrote about housing chains for hermit crabs that result from evictions.)  A vacancy chain in a housing market can be thought of as a moving chain: someone moves into a vacant house or apartment (perhaps a newly constructed one), and someone else moves into the home they vacated, and so on, until the chain ends when a person who was in some different market (e.g. in rental housing, or in a distant location) moves into the last identifiable home in the chain.

Here are two papers that explore what happens when newly constructed housing is relatively expensive. They find that the chain often reaches much more moderately priced housing, i.e. adding to the stock of expensive housing also makes more affordable, existing housing available to new occupants.

The first paper draws on data from a dozen American cities (from Atlanta to San Francisco):

The effect of new market-rate housing construction on the low-income housing market, by Evan Mast, Journal of Urban Economics, Available online 27 July 2021,

Abstract: I illustrate how new market-rate construction loosens the market for lower-quality housing through a series of moves. First, I use address history data to identify 52,000 residents of new multifamily buildings in large cities, their previous address, the current residents of those addresses, and so on for six rounds. The sequence quickly reaches units in below-median income neighborhoods, which account for nearly 40 percent of the sixth round, and similar patterns appear for neighborhoods in the bottom quintile of income or percent white. Next, I use a simple simulation model to roughly quantify these migratory connections under a range of assumptions. Constructing a new market-rate building that houses 100 people ultimately leads 45 to 70 people to move out of below-median income neighborhoods, with most of the effect occurring within three years. These results suggest that the migration ripple effects of new housing will affect a wide spectrum of neighborhoods and loosen the low-income housing market.


A more recent working paper draws on data from metropolitan Helsinki and reaches similar conclusions:

Bratu, Cristina and Harjunen, Oskari and Saarimaa, Tuukka, City-wide Effects of New Housing Supply: Evidence from Moving Chains (August 31, 2021). VATT Institute for Economic Research Working Papers 146, Available at SSRN: or

Abstract: We study the city-wide effects of new, centrally-located market-rate supply using geo-coded total population register data from the Helsinki Metropolitan Area. The supply of new market rate units triggers moving chains that quickly reach middle- and low-income neighborhoods and individuals. Thus, new market-rate construction loosens the housing market in middle- and low-income areas even in the short run. Market-rate supply is likely to improve affordability outside the sub-markets where new construction occurs and to benefit low-income people.



Vacancy chains in housing for hermit crabs   

Blum, Y., A.E. Roth, and U.G. Rothblum "Vacancy Chains and Equilibration in Senior-Level Labor Markets," Journal of Economic Theory, 76, 2, October 1997, 362-411.

Wednesday, January 19, 2022

Dialysis provider DaVita enters the transplant space

 Here's the press release:

DaVita Acquires MedSleuth, Deepens Efforts to Improve Transplant Experience. Transplant software company helps DaVita bolster its presence along the kidney care journey

" DaVita Inc. today announced its acquisition of transplant software company MedSleuth. Working with transplant centers across the U.S., MedSleuth aims to create greater connectivity among transplant candidates, transplant centers, physicians and care teams to help improve the experience and outcomes for kidney and liver transplant patients.

"With this acquisition, DaVita deepens its efforts to fuel transplant innovation, underscoring its commitment to improve care at every stage and setting along a patient's kidney care journey.

"Kidney transplantation is a life-changing option for most people with kidney failure, one that's limited today by supply and complexity," said Javier Rodriguez, CEO for DaVita. "MedSleuth has built a powerful platform that can help increase patients' access to transplantation. We're looking forward to supporting the team to accelerate innovation and help streamline the transplant process for transplant candidates, transplant centers, physicians and care teams."

"From lack of supply to meet the demand to understanding and staying on top of the complex process from workup to wait list to transplant, the U.S. transplant system can be complicated to navigate.

"MedSleuth's innovative software can help not only streamline the process of evaluating candidates and keep them active on the waitlist but may also help increase the rate of transplantation through living donation. The software can also make it easier for transplant candidates' doctors and care teams to help support them along the transplant journey.

"BREEZE™, MedSleuth's flagship product, helps remove certain barriers for potential kidney and liver donors and recipients by remotely gathering relevant clinical and demographic information and sharing it with participating transplant centers—effectively streamlining the transplant process, from candidate evaluation through donor and recipient follow-up.

"MATCHGRID™, MedSleuth's paired exchange platform, uses optimization algorithms to find chains for paired donation. This helps transplant center clinicians rapidly match living organ donors with recipients who have willing, healthy but incompatible donors."

HT; Martha Gershun

Tuesday, January 18, 2022

Evictions and coalitions in the housing market of hermit crabs--shell trafficking in the wild

 I've previously blogged about the observation that hermit crabs, who live in the shells of other animals and have to get new shells as they grow, sometimes engage in chains of exchange, that resemble kidney exchange chains, or vacancy chains in labor markets.

In particular, they resemble kidney exchange chains initiated by a deceased donor, in this case initiated by an empty shell.

 Here's a new article about hermit crabs which reports that they also engage in something that looks like organ trafficking, with a hermit crab being forcibly removed from its shell by two smaller crabs acting in concert, so that one of them may occupy the now vacant shell while the other moves into the shell of its partner in crime.

Laidre, Mark E. "The Architecture of Cooperation Among Non-kin: Coalitions to Move Up in Nature’s Housing Market." Frontiers in Ecology and Evolution (2021): 928.

"Coalitions typically involve two individuals (a pair), with a third individual being the target that the two-member coalition seeks to evict from its shell (Figure 1). Both members of the coalition have shells of their own, but these individuals and their shells are virtually always smaller than that of the target individual and its shell. Sometimes, based on the commotion and struggle generated during an attempted eviction, additional individuals—beyond the target and the core two-member coalition—are attracted to the area. These additional individuals—referred to as “third parties” or “bystanders”—are not part of the actual coalition, since they do not help at all to evict the target. Generally, third parties simply wait in the vicinity and sometimes position themselves in a social chain, which emanates from the back of the shell of one or both of the coalition members (Figure 2). This positioning in a social chain enables third parties to indirectly benefit, since in the event an eviction succeeds, it can catalyze a succession of back-to-back shell swaps (see Laidre, 2019a). Third parties are thus, in effect, “free riders” (Sigmund, 2010), since their positioning around the coalition offers no advantage whatsoever to the coalition itself as it works to evict the target. Indeed, whether third parties are positioned in a chain or not, they merely wait, performing no pulling actions and never adding any strength or providing any help to the two-member coalition. Interestingly, based on precisely where third parties position themselves, some may potentially even undermine the coalition (see below), effectively acting not merely as “free riders” but as “cheaters” (Sigmund, 2010). Finally, if too many bystanders accumulate, it can lead to chaotic jockeying and repositioning, with the original coalition separating.

"Whether with third parties present or not, the two members of the coalition attempt to physically evict the target. The target remains flipped on its back (i.e., with the dorsal side of its shell on the ground) and the opening of the target’s shell faces upward, allowing both coalition members to use their claws and legs to grab at and pull the anterior portion of the target’s body. As the coalition forcibly pulls, the target attempts to resist by clinging inside its shell. Typically, the two coalition members both pull simultaneously; though at times the two may alternate attempts at pulling, each doing so sequentially as one or the other member briefly rests. Both members of a coalition appear strongly involved, in terms of time and effort. Yet coalitions are not always successful. In some cases, one or both coalition members may give up; or the target individual may manage to flip itself over, escape from being pinned down, and run away. If a coalition is successful at evicting the target, the time till eviction occurs can vary widely, from just minutes up to hours (Laidre, personal observation). Once a coalition is successful and the target individual is evicted from its shell, then the evictee is pushed to the side and remains naked and shell-less as one of the coalition members moves into its now empty shell."



Saturday, July 21, 2012