Friday, August 31, 2018

The market for influence, by Fainmesser and Galeotti (the movie)

Here's a nicely done "trailer" for a paper by Itay Fainmesser and Andrea Galeotti. It's a three minute video...
"The Market for Influence" by Itay Fainmesser and Andrea Galeotti from Itay Fainmesser on Vimeo.

For you dinosaurs who prefer an abstract to a trailer, here it is, with the whole movie paper at the link.

The Market for Influence

Itay P Fainmesser

Johns Hopkins University - Carey Business School

Andrea Galeotti

University of Essex
Date Written: August 2018


Influencer marketing is the fast-growing practice in which marketers purchase product endorsements from influencers — who are individuals with many followers and strong reputations in niche markets. This paper develops a model of the market interactions between influencers, followers, and marketers. Influencers trade off the increased revenue they obtain from more paid endorsements with the negative impact that this has on their followers’ engagement, which in turn affects the price marketers are willing to pay for their endorsement. Our analysis provides testable predictions on how the price that influencers receive depends on the size of their audience and how an improvement in the online search technology affects influencers’ competition for followers and marketers. We show that, in equilibrium, over- and under-provision of paid endorsements coexist. We evaluate the strategic effects of recent, transparency-motivated policy interventions implemented by competition authorities in the US and Europe, requiring influencers to clearly indicate marketer-sponsored content.

Fainmesser, Itay P and Galeotti, Andrea, The Market for Influence (August 2018). Available at SSRN: or
  Before the paper was made into a movie, I had earlier posted about it and a related news article here:

Wednesday, July 18, 2018

Blasphemy as a repugnant transaction. versus free speech as a protected transaction

Here's a headline from The Guardian which basically tells the whole of the news story:

Muhammad cartoon contest in Netherlands sparks Pakistan protests
Islamist leader says ‘only jihad’ is sufficient to punish ‘blasphemous’ Wilders stunt

"The Dutch prime minister, Mark Rutte, has termed the event “disrespectful” but defended the right to hold it on the grounds of freedom of expression.

"On Monday, Pakistan’s senate passed a resolution condemning the competition and Khan vowed to take up the issue at the UN general assembly in September. He said Islamic countries should cooperate to create laws against blasphemy similar to those against Holocaust denial in European countries."

Here's the story in the Pakistani newspaper Dawn:

TLP rally on its way to Islamabad as demand for expulsion of Netherlands envoy remains unfulfilled

"The emotions of all Muslims against blasphemous caricatures is the same," Chaudhry, the information minister added. "A joint front is imperative against blasphemy."

Update: Far-right Dutch MP cancels Muhammad cartoon competition
Geert Wilders drops plans for controversial contest in November following death threats

"“To avoid the risk of victims of Islamic violence, I have decided not to let the cartoon contest go ahead,” the far-right opposition politician said in a written statement on Thursday night.

"Wilders, who for years has lived under round-the-clock protection because of death threats sparked by his fierce anti-Islam rhetoric, said he does not want others put in danger by the contest he planned for November."

Thursday, August 30, 2018

James Mirrlees 1936-2018

Here's the brief initial announcement from the University of Cambridge:

Professor Sir James Mirrlees 1936-2018

"It is with great sadness that I write to say that Professor Sir James Mirrlees has passed away. Jim died yesterday at his home in Cambridge.

"Jim is widely known as the author of some of the most luminous and influential papers in modern economics. He was awarded a Nobel Prize for his work in public economics in 1996. But over and above his great intellectual achievement, Jim was widely respected and held in great affection for his generosity in encouraging and supporting economists from all over the world."
Sanjeev Goyal FBA
Chair, Faculty of Economics

Jim last visited Stanford less than a year ago, last October, to participate in a conference remembering Ken Arrow.
Here's a video of his talk, which begins with an introduction by John Shoven, explaining a little-known early connection between Jim and Ken:

European Collaboration on Kidney Exchange (program for meeting in Italy)

Note the various discussions of transnational kidney exchange...some of that will involve exchange within the EU, and some will involve dealing with the very diverse European views on extending kidney exchange to include pairs from countries that aren't able to pay for it, i.e. on global kidney exchange.


ENCKEP Meeting
August 30th – Sept 1st 2018
Hotel Palazzo Viceconte, Via S. Potito 7, Matera, Italy

Thursday, August 30 2018

14:00 - 14:15    Welcome and introduction. David Manlove (UK)
14:15 - 15:15    Summary of activity on data collection and summarisation of best practices in KEPs
(ENCKEP Working group 1) Peter Biro (HU)
- Summary of Handbook 1: Kidney Exchange Practices in Europe.
- Summary of Handbook 2: Modelling and Optimisation in the European Kidney Exchange Programmes.

15:15- 15:45     Coffee-break

15:45 – 16:45    Round-table: Moderators: Lisa Burnapp (UK), Bernadette Haase (NL)
Consolidating the ENCKEP view on ethical and legal aspects of transnational KEPs
Discussants: Lucrezia Furian (IT), Frank Dor (UK), Franco Citterio (IT)
ü  inclusion of altruistic donors and managing reciprocity between participating countries
ü  inclusion of compatible pairs: what criteria should we use?
ü  deceased donors to initiate ‘chains’: should we and could we?

17:00 - 18:00 Inputs for ENCKEP
ü  Bridging clinical and OR aspects of KEPs. Paolo Ferrari (CH)
ü  Alternative approaches for transplant recipients with antibodies- A UK perspective. Nizam Mamode (UK)

Friday, August 31 2018

09:00 – 11:00 Working Group 1: Data collection and summarisation of best practices in KEPs
                        Moderator: Lisa Burnapp
ü  Developing an ethical and legal framework for transnational KEPs.

11:00 - 11:30    Coffee break

11:30 - 13:00    Working Group 2: National KEPs: models, optimisation methods and technology                          Part 1.             Moderator: Paolo Tubertini

ü  Findings of Handbook 1: proposing a standardised framework for designing KEPs based on identified optimality criteria and data models).
ü  Kick-off discussion on Handbook 2 (“Standards to describe and assess the structure and efficiency of existing and proposed KEPs”).
ü  Publications arising from the handbooks

13:00 - 14:00    Lunch

14:00 - 14:30    Working Group 2: National KEPs: models, optimisation methods and technology                         Part 2. Moderator: TBC
14:30 - 15:30    Working Group 3: Transnational KEPs and practical collaboration - Part 1. Moderator: Xenia Klimentova
What can we learn from cadaveric transnational programs?
o   Scandiatransplant experience. Tommy Andersson (SE)
o   Eurotransplant experience Jacob de Boer (NL)
·        Presentations on current pilot programs on transnational KEP
o   Scandiatransplant (if started)
o   Austria- Czech Republic. Tomas Marada (CZ)
15:30 - 16:00    Coffee break

16:00 - 17:00    Working Group 3: Transnational KEPs and practical collaboration. - Part 2. Moderator: Xenia Klimentova
Spain-Italy-Portugal. Maria Valentin (ES), Paola Di Ciaccio (IT), Catarina Bolotinha/Ana França (PT).

Discussion on further steps and developments.
17:00 - 17:30    Working Group 4: Dissemination of results
Moderator: Christian Jacquelinet
Discuss publication policy of Action deliverables, and dissemination tools such as handbooks, publications, software, conference presentations and via the Action website.

Saturday, September 1 2018

09:00 – 16:30 Training School for clinicians

09:00 - 09:30    Presentation of ENCKEP Action. David Manlove (UK)

09:30 - 11:00
l  European KEPs: Theory into Practice (Aline Hemke (NL)/Lisa Burnapp (UK)/Tomas Marada (CZ) /Karine Hadaya (CH)).  Focusing on practicalities and logistics

11:00 - 11:30    Coffee break

11:30 - 12:30
l  National authorities: experience with using optimisation software.  Matthew Robb (UK), Catarina Bolotinha (PT), Maria Valentin (SP)
l  Italy, Portugal and Spain: collaboration on KEPs. Maria Valentin (ES), Catarina Bolotinha/Ana França (PT), Paola Di Ciaccio (IT)

12:30 - 14:00    Lunch

14:00 - 15:00    Perspectives from the USA
l  UNOS and KEPs in the USA. Ruthanne Leishman.
l  Market Failures. Itai Ashlagi.

15:00 - 15:30    Coffee break

15:30 - 16:30    Ethical and legal issues relating to transnational KEPs
                        Moderators: Lisa Burnapp (UK), Bernadette Haase (NL)
l  Introductory talk (title TBC) Martin Buijsen (NL)

Wednesday, August 29, 2018

Global kidney exchange: followup report on the first GKE chain

Here's a report, 3 years after, of the first global kidney exchange chain. Among the authors are the Filipino physicians who are providing ongoing care for the Filipino donor and recipient:

Complete Chain of the First Global Kidney Exchange Transplant and 3-yr Follow-up



Global Kidney Exchange (GKE) offers an opportunity to expand living renal transplantation internationally to patients without financial means. These international pairs are entered into a US kidney exchange program that provides long-term financial support in an effort to identify opportunities for suitable exchanges for both these international pairs and US citizens.


While the promise of GKE is significant, it has been met with ethical criticism since its inception in 2015. This paper aims to demonstrate the selection process and provide >3 yr of follow-up on the first GKE donor and recipient from the Philippines.

Design, setting, and participants

The first GKE transplant occurred with a young Filipino husband and wife who were immunologically compatible, but lacked the financial means to continue hemodialysis or undergo a kidney transplant in their home country. The pair was enrolled in the Alliance for Paired Donation matching system, several alternative kidney exchanges were identified, and the pair subsequently underwent renal transplantation and donation in the USA financed by philanthropy. The resulting nonsimultaneous extended altruistic chain provided transplantation for the Filipino husband and 11 US patients.

Outcome measurements and statistical analysis

The Filipino donor and recipient were followed by transplant professionals in both the Philippines and the USA. Follow-up data were maintained as required by the Organ Procurement and Transplantation Network in the USA.

Results and limitations

The Filipino donor has normal blood pressure and renal function, and the Filipino recipient is doing well 3.5 yr after their donation and transplantation.


While criticisms of GKE highlight concerns for possible exploitation of financially disadvantaged groups, these results demonstrate that these concerns did not come to fruition, and the outcome experienced by the GKE donor and recipient (and other US participants) was successful.

Patient summary

The first Filipino Global Kidney Exchange (GKE) donor-recipient pair continues to be followed by both US and Filipino transplant centers. Both are in good health, support the GKE program, and advocate for its expansion.

Tuesday, August 28, 2018

Blockchain and legal but repugnant markets--a guest post by Stephanie Hurder

Below is a guest post, by Stephanie Hurder — a Harvard Economics Ph.D. (who I've blogged about before, here, and here) and a founder of blockchain economics startup Prysm Group (that I’ve blogged about here). She discusses how blockchain may impact repugnant markets.

As Al has written about for years, repugnance -- the distaste for certain kinds of transactions -- can be a serious constraint on markets.   Repugnance can stem from numerous sources, such as a fear of coercion or of a slippery slope.  And while the constraints created by repugnance sometimes end up incorporated in to law, they do not need to be legal to have significant impact.  Businesses may voluntarily choose not to provide services that some set of consumers might find repugnant, in order to maintain their brand reputation and prevent a loss of those customers.

Firms that engage in legal, adult activities -- such as pornography and the sale of sex toys -- have significant issues accessing financial services due to the constraints imposed by repugnance.  Most commercial banks include “morality clauses” forbidding service of businesses engaging in adult activities, for reputational reasons.   Newer payment services that would like to serve “repugnant” industries are constrained by these more conservative organizations, with whom they must do business in order to effectively process payments and offer services.

Stripe, the payments processor, has publicly discussed this phenomenon on their blog.  Stripe was approached by OMGYes, a website that provides actionable, research-backed information on sex.  They write:

The business approached us and we were eager to work with them, but after a month of deliberations, our financial partners did not agree. Instead, because the website has explicit tutorials, it still falls under the umbrella of unsupportable businesses. While we were not able to persuade our financial partners this time around, we will continue to holistically look at and advocate for businesses that sell adult products and services.

-           -           -

By now, almost all industries are exploring how to leverage the economic benefits of blockchain, especially those arising from blockchain’s ease of verification and decentralization.  One type of use case with significant potential is using blockchain to provide services to markets constrained by repugnance. 

Cryptocurrencies such as Bitcoin are a potential payments solution for industries not served by traditional financial service providers.  However, a payment system by itself is not enough -- the anonymity of some cryptocurrencies can increase the probability that genuinely coercive or even illegal activities will take place.  Effective platforms serving repugnance markets will need to combine the decentralized benefits of blockchain and cryptocurrencies with more traditional levers of market design, such as reputation.

An example of a company doing exactly this is is an Ethereum-based platform for individuals engaged in the adult industry.  It provides secure, decentralized transfer of payments for adult services.  It also includes pseudonymous reputation and user information (such as age verification and relevant health information) to help service providers vet customers and vice versa.  Two-party escrow provides financial incentives for users to behave cooperatively. CEO, Leah Callon-Butler, writes:

Blockchain is a technology crying out for a use-case and brings together several different blockchain-based technologies, to demonstrate unprecedented real-world utility through application to an industry that is sorely in need of emancipation from centralised bodies who have assumed the role of moral arbiter for too long.

While platforms like open the possibility for market participants to work around roadblocks imposed by repugnance, they face many of  the same market design and data management challenges as other industries.  How will sensitive information (such as health data) be verified and provided to the market, while preserving privacy?  How will the platform ensure that users banned for poor behavior do not create new identities?  Innovative solutions to these issues can inform market design more broadly.

It will also be interesting to see how the “traditional” financial system reacts to blockchain platforms like  Luke Coffman at Harvard has shown that introducing an intermediary in a business transaction can lessen the punishments for “immoral” behavior that consumers give to companies.  How many steps of separation -- and of what kind -- will be required between traditional banks and platforms like so that markets constrained by repugnance can finally be served?

Monday, August 27, 2018

Five approaches to the opioid crisis, by pharmacologists, doctors, insurers, prosecutors, and legislators

Five very different approaches to the opioid crisis--by
1. pharmacologists/biologists, 2. physicians, 3. payers,  4. prosecutors, and 5.legislators:

1. From PNAS:
Safer opioids may be on the horizon, but mitigating addiction is a long shot, by Jyoti Madhusoodanan

2. From Science:
Opioid prescribing decreases after learning of a patient’s fatal overdose, by
Jason N. Doctor, Andy Nguyen, Roneet Lev, Jonathan Lucas, Tara Knight, Henu Zhao, Michael Menchine

3. From the Chicago Trib, and from Stat:
Chicago limits opioid prescriptions for city employees

Tapered to zero: In radical move, Oregon’s Medicaid program weighs cutting off chronic pain patients from opioids

4. From Reuters:
New York sues OxyContin maker Purdue Pharma over opioids

5. From the NY Times
Congress Is Writing Lots of Opioid Bills. But Which Ones Will Actually Help?

And here's an article from the NY Times on the magnitude of the crisis:

Bleak New Estimates in Drug Epidemic: A Record 72,000 Overdose Deaths in 2017: Fentanyl is a big culprit, but there are also encouraging signs from states that have prioritized public health campaigns and addiction treatment.

"Strong synthetic opioids like fentanyl and its analogues have become mixed into black-market supplies of heroin, cocaine, methamphetamine and the class of anti-anxiety medicines known as benzodiazepines."

Sunday, August 26, 2018

Signaling and matching in an online labor market, by Horton and Johari

Here's a paper on signaling and matching in a prominent but un-named online labor market that is readily identifiable.

Engineering a Separating Equilibrium

John J. Horton and Ramesh Johari
August 14, 2018

Abstract: This  paper  explores  whether  platform-created  signaling opportunities can move designed markets to more desirable equilibria.  In a large on-line  labor  market,  buyers  were  given  the  opportunity  to  signal  their relative  preferences  over  price  and  quality.   The  intervention  caused substantial sorting by sellers to buyers of the right “type.”  However, sellers clearly tailored their bids to the type of buyer they faced, bidding up against sellers with a high revealed willingness to pay.  Despite this “markup,” a separating equilibrium was sustained over time, suggesting buyers found revelation incentive compatible.  We find evidence that informative signaling improved matching efficiency and match quality.

"The signaling opportunity was simple:  when posting a job opening,  employers selected one of three “tiers” to describe the kinds of applicants they were most interested in:  (1) Entry level:  “I am looking for [workers] with the lowest rates.”;  (2) Intermediate:  “I am looking for a mix of experience and value.”; (3) Expert:  “I am willing to pay higher rates for the most experienced [workers].”  We refer to these tiers as “low,” “medium,” and “high,” respectively.   When  the  signaling  opportunity  was  introduced  market-wide  (which occurred after an experimental period), the tier choice was revealed publicly to all job-seeking workers."