Tuesday, August 31, 2021

Challenge trials for Covid-19 Delta variant

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

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

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

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

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

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

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

Monday, August 30, 2021

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

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

Symposium on Integrity in Research

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

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

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

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

"Keynotes and formats

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

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

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

Registration, access and program

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

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

Saturday, August 28, 2021

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

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

"Robert B. Wilson, Biographical

"1.Overview at age 83

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

Friday, August 27, 2021

OnlyFans announces then reverses a ban on explicit sexual content

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

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

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

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


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


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


And here's a followup from Fortune:

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

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

Thursday, August 26, 2021

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

 The journal OEconomia has a review of the book 

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

(From the publisher's page:

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

Here is the (16 page) review in OEconomia:

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

It opens as follows:

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

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

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

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

Wednesday, August 25, 2021

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

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

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

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

Tuesday, August 24, 2021

Unraveling for consulting: recruiting for next summer has begun.

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

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



Monday, August 23, 2021

A podcast about (and for) kidney donors

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

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

Sunday, August 22, 2021

Disruptive marketplaces in HBR, by Clifford Maxwell and Scott Kominers

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

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

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


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

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

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

Saturday, August 21, 2021

Introduction to NLDAC (the National Living Donor Assistance Center)

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

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

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

Friday, August 20, 2021

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

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

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

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


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

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

Thursday, August 19, 2021

Radical content on YouTube, in PNAS

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

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

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

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

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

Wednesday, August 18, 2021

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

 Irene Lo writes:

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


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

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

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

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


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


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


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

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


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

Tuesday, August 17, 2021

Stanford SITE seminar: Dynamic Games, Contracts, and Markets, Aug 18-20


  • Simon Board, University of California, Los Angeles
  • Gonzalo Cisternas, Massachusetts Institute of Technology
  • Mira Frick, Yale University
  • George Georgiadis, Northwestern University
  • Andrzej Skrzypacz, Stanford GSB
  • Takuo Sugaya, Stanford GSB

The idea of this session is to bring together microeconomic theorists working on dynamic games and contracts with more applied theorists working in macro, finance, organizational economics, and other fields. First, this is a venue to discuss the latest questions and techniques facing researchers working in dynamic games and contracts. Second, we wish to foster interdisciplinary discussion between scholars working on parallel topics in different disciplines, in particular, helping raise awareness among theorists of the open questions in other fields.

This is a continuation of successful SITE annual sessions 2013-2020. In previous years, we attracted people from economics, finance, operations research, political economy, and other related fields, ranging from Ph.D. students to senior professors. We hope to have a similar number of attendees this year as in the past. Specific topics likely to be covered include repeated and stochastic games, dynamic optimal contracts, dynamic market pricing, reputation, search, and learning and experimentation.

In This Session

Wednesday, August 18, 2021

AUG 18
9:00 AM - 9:45 AM

Wealth Dynamics in Communities

Presented by: Daniel Barron (Northwestern University)
Co-author(s): Yingni Guo (Northwestern University) and Bryony Reich (Northwestern University)

This paper develops a model to explore how favor exchange in communities influences wealth dynamics. We identify a key obstacle to wealth accumulation: wealth crowds out favor exchange. Therefore, low-wealth households are forced to choose between growing their wealth and accessing favor exchange within their communities. The outcome is that some communities are left behind, with wealth disparities that persist and sometimes even grow worse. Using numerical simulations, we show that place-based policies encourage both favor exchange and wealth accumulation and so have the potential to especially benet such communities.

AUG 18
9:45 AM - 10:00 AM


AUG 18
10:00 AM - 10:45 AM

Optimal Dynamic Allocation: Simplicity through Information Design

Presented by: Faidra Monachou (Stanford University)
Co-author(s): Itai Ashlagi (Stanford University) and Afshin Nikzad (University of Southern California)

We study dynamic nonmonetary markets where objects are allocated to unit-demand agents with private types. An agent’s value for an object is supermodular in her type and the quality of the object, and her payoff is quasilinear in her waiting cost. We analyze direct-revelation mechanisms that elicit agents’ types and assign them to objects over time. We identify the welfare-maximizing mechanism and show that it can be implemented by a first-come first-served wait-list with deferrals when the
marketmaker can design the information disclosed to agents about the objects. The optimal disclosure policy pools adjacent object types.

AUG 18
10:45 AM - 11:00 AM


AUG 18
11:00 AM - 11:45 AM

Probabilistic Assortative Matching under Nash Bargaining

Presented by: Nicolas Bonneton (University of Mannheim)
Co-author(s): Christopher Sandmann (London School of Economics)

This paper re-visits the canonical random search and matching model with Nash bargaining. By introducing pair-specific production shocks, our framework generates meeting-contingent match outcomes that are random. We provide a robust characterization of probabilistic matching patterns for any non-stationary environment, generalizing results by Shimer and Smith (2000). We nd that, although their prediction of single-peaked preferences over meetings is robust, search frictions upset positive assortative matching across well-assorted pairs. As a second contribution, we show that the non-stationary random search matching model is a mean eld game, and admits a representation as a system of forward-backward stochastic differential equations. This representation affords a novel existence and uniqueness result, casting doubt on the robustness of multiple self-fulfilling equilibrium paths frequently reported in the literature.

Thursday, August 19, 2021

AUG 19
9:00 AM - 9:45 AM

Price Experimentation in Confidential Negotiations

Presented by: Jangwoo Lee (McCombs School of Business, University of Texas at Austin)

I develop a model in which a long-lived seller concurrently negotiates with multiple long-lived buyers over two periods. Within this framework, I consider two protocols: a public negotiation process and a confidential negotiation process. In the confidential negotiation process, buyers competitively engage in “price experimentation”: they sacrifice initial profits so that they can enjoy informational advantages over competitors later. Due to this channel, the seller benefits from (1) maintaining confidentiality over past offers and (2) reducing the number of buyers in the confidential negotiation process, even without any entry cost.

AUG 19
9:45 AM - 10:00 AM


AUG 19
10:00 AM - 11:45 AM

Large-Sample Rankings of Information Structures in Games

Presented by: Mira Frick (Yale University)
Co-author(s): Ryota Iijima (Yale University) and Yuhta Ishii (Pennsylvania State University)



AUG 19
10:45 AM - 11:00 AM


AUG 19
11:00 AM - 11:45 AM

The Cost of Optimally Acquired Information

Presented by: Alexander W. Bloedel (Stanford University)
Co-author(s): Weijie Zhong, (Stanford Graduate School of Business)

This paper develops a theory for the expected cost of optimally acquired information when information can be acquired sequentially and there is no explicit cost of delay. We study the “reduced-form” Indirect Cost functions for information generated by sequential minimization of a “primitive” Direct Cost function. The class of Indirect Costs is characterized by a recursive condition called Sequential Learning-Proofness. This condition is inconsistent with Prior Invariance: Indirect Costs must depend on the decision-maker’s prior beliefs. 

We show that Sequential Learning-Proofness provides partial optimality foundations for the Uniformly Posterior Separable (UPS) cost functions used in the rational inattention literature: a cost function is UPS if and only if it is an Indirect Cost that (i) satisfies a mild regularity condition or, equivalently, (ii) is generated (only) by Direct Costs for which the op timal sequential strategy involves observing only Gaussian diffusion signals. We characterize the unique UPS cost function that is generated by a Prior-Invariant Direct Cost; it exists only when there are exactly two states. 

We also propose two specific UPS cost functions based on additional optimality principles. We introduce and characterize Total Information as the unique Indirect Cost that is Process Invariant when information can be decomposed both sequentially and “simultaneously”: it is uniquely invariant to the “merging” and “splitting” of experiments. Under regularity conditions, Mutual Information is the unique Indirect Cost that is Compression-Invariant when as pects of the state space can be “freely ignored”: it is uniquely invariant to the “merging” and “splitting” of states. We argue that Total Information and Mutual Information represent the normatively ideal costs of, respectively, “producing” and “processing” information. 


Friday, August 20, 2021

AUG 20
9:00 AM - 9:45 AM

Optimal Feedback in Contests

Presented by: George Georgiadis (Northwestern University)
Co-author(s): Jeffrey Ely (Northwestern University), Sina Khorasani (UC San Diego), and Luis Rayo (Northwestern University)

We derive optimal contests for environments where output takes the form of breakthroughs and the principal has an informational advantage over the contestants. Whether or not the principal is able to provide real-time feedback to contestants, the optimal prize allocation is egalitarian: all agents who have succeeded in a pre-specified time interval share the prize equally. When providing feedback is feasible, the optimal contest takes a stark cyclical form: contestants are fully apprised of their own success, and at the end of each fixed-length cycle, they are informed about peer success as well.

AUG 20
9:45 AM - 10:00 AM


AUG 20
10:00 AM - 10:45 AM

Dynamic Amnesty Programs

Presented by: Sam Kapon (New York University)

A regulator faces a stream of agents each engaged in crime with stochastic returns. The regulator designs an amnesty program, committing to a time path of penalty reductions for criminals who self-report before they are detected. In an optimal time path, the intertemporal variation in the returns from crime can generate intertemporal variation in the generosity of amnesty. I construct an optimal time path and show that it exhibits amnesty cycles. Amnesty becomes increasingly generous over time until it hits a bound, at which point the cycle resets. Agents engaged in high return crime self-report at the end of each cycle, while agents engaged in low return crime self-report always.

AUG 20
10:45 AM - 11:00 AM


AUG 20
11:00 AM - 11:45 AM

Screening for Breakthroughs

Presented by: Ludvig Sinander (Northwestern University)
Co-author(s): Gregorio Curello (University of Bonn)

We identify a new and pervasive dynamic agency problem: that of incentivising the prompt disclosure of productive information. To study it, we introduce a model in which a technological breakthrough occurs at an uncertain time and is privately observed by an agent, and a principal must incentivise disclosure via her control of the agent’s utility. We uncover a striking deadline structure of optimal mechanisms: they have a simple deadline form in an important special case, and a graduated deadline structure in general. We apply our results to the design of unemployment insurance schemes.