Showing posts with label school choice. Show all posts
Showing posts with label school choice. Show all posts

Saturday, May 22, 2021

School choice in Sweden (and in Swedish), by Andersson and Roth

 Tommy Andersson and I wade into the school choice debate in Sweden in the Dagens Samhalle, arguing in favor of unified enrollment and the deferred acceptance algorithm. Google translate does a reasonable job of translation:

Professorer: Så kan skolvalet leda till minskad skolsegregation

Google Translate: "Professors: This is how school choice can lead to reduced school segregation

"If you seriously want to break school segregation, the choice of school needs to be maintained. But it is important that you choose the "right" method for allocating school places so that tactical school choices are eliminated, write professors Tommy Andersson and Alvin E Roth."

Sunday, May 16, 2021

The common app and the growth of applications to selective colleges, by Brian Knight and Nathan Schiff

A pair of papers study the Common App, how it is used disproportionally by selective universities and liberal arts colleges, to which applications have increased over time.  The papers focus on how this has increased student choice. 

There's a parallel set of arguments made elsewhere, particularly in connection with application to medical residencies, that too many applications increase congestion in the admissions process. 

The Common Application and Student Choice, By Brian Knight and Nathan Schiff, AEA Papers and Proceedings 2021, 111: 460–464, https://doi.org/10.1257/pandp.20211042



And here's a longer companion paper:

Reducing Frictions in College Admissions: Evidence from the Common Application by Brian Knight and Nathan Schiff, April 17, 2020

Abstract: College admissions in the U.S. is decentralized, creating frictions that limit student choice. We study the Common Application (CA) platform, under which students submit a single application to member schools, potentially reducing frictions and increasing student choice. The CA increases the number of applications received by schools, reflecting a reduction in frictions, and reduces the yield on accepted students, reflecting increased choice. The CA increases out-of-state enrollment, especially from other CA states, consistent with network effects. CA entry changes the composition of students, with evidence of more racial diversity, more high-income students, and imprecise evidence of increases in SAT scores.




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For a look at applications through the other end of the telescope, see

Wednesday, April 28, 2021

Selective NYC high schools aren't as hard to get into as is sometimes reported: Sam Abrams in the Columbia Journalism Review

 In the Columbia Journalism Review, Sam Abrams explains how data from NYC's deferred acceptance algorithm for assigning students to schools is often misunderstood in the press, when it comes to reporting on how selective the schools are.

Getting Education Data Right: The Case of High School Admissions  By Samuel E. Abrams

"The trouble with the story about high school admissions begins with official data. The admissions numbers in the annual high school directories published by New York City’s Department of Education are indeed alarming. Eight consecutive schools in the 2019 directory, for example, exhibited daunting odds: Bard High School Early College, 30 applicants per seat; Baruch College Campus High School, 44; Beacon High School, 19; Business of Sports School (BOSS), 13; Central Park East High School, 37; Chelsea Career and Technical Education High School, 14; City College Academy of the Arts, 22; and The Clinton School, 21. These odds translate into acceptance rates ranging from 2.3 percent, in the case of Baruch, to 7.7 percent, in the case of BOSS. 

"But these students are not applicants in the conventional sense. They are students who rank a school by order of preference as one of up to 12 with which they would like to match. This process—introduced in 2004 and derived from the National Resident Matching Program for doctors introduced in 1952—employs an algorithm allowing only one match. Accordingly, if every eighth-grader in New York City exercised his or her right to list 12 schools, each school, on average, could in turn accept only one of 12 students, or 8.3 percent of applicants.

...

"I began encountering this reporting problem in 2005, when the Times published an article on then-Mayor Michael Bloomberg’s plans to create several new high schools to address the surplus demand for seats in exam and screened schools. The Times reported that Beacon had 6,000 applicants for 250 seats the previous year, meaning an acceptance rate of 4.2 percent.

"As a teacher at Beacon at the time, I knew the admissions process from the inside and emailed a correction to the paper: 6,000 students ranked Beacon as one of up to 12 schools in which they were interested; about 1,800 students submitted the requisite portfolio of their best work and visited the school for the mandated interview; and approximately 500 offers were made to fill 250 seats. This meant an acceptance rate of about 28 percent if all 1,800 applicants ranked Beacon first, which is highly improbable, given that approximately 50 percent of applicants to Beacon today who fulfill application requirements rank the school first. But that correction went nowhere, and I resigned myself to explaining the numbers to anxious parents fretting that their children had no chance of getting into Beacon given what they had read in the Times.

...

"Following the 2017 article about 10 of the city’s high schools being more selective than Yale, I wrote a letter to the Times. As that letter went unacknowledged and as the newspaper did not run another letter to elucidate the process, I published a critique on the Web site of a research center I run at Teachers College, Columbia University. That critique led to an article published by Chalkbeat and another by Phi Delta Kappan, which interviewed Alvin Roth, a professor at Stanford who shared the Nobel Prize in economics in 2012 for work decades earlier on market design and who, with two other economists, Atila Abdulkadiroglu and Parag Pathak, developed the algorithm used by the DOE. Roth explained that the Times had indeed greatly exaggerated the number of applicants because the algorithm pulled students from the applicant pool once they were matched. “If I applied to you as my seventh choice, and I got accepted by my first choice, I wasn’t rejected by you,” Roth said. “You never saw me.”

"With a matching algorithm, the closest one can truly get to an acceptance rate is a match rate through adding the number of students who matched with a particular school to the number of students who matched with a school they ranked lower than that school and then dividing the number of matches by that sum.

...

"What is nevertheless certain is that the algorithm developed by Roth with Abdulkadiroglu and Pathak has significantly streamlined the enrollment process in New York. The three economists developed the algorithm, they wrote in a 2005 article published in the American Economic Review, to “relieve the congestion of the previous offer/acceptance/wait-list process” that conferred “some students multiple offers” and “multiple students … no offers.:


Thursday, April 8, 2021

Congestion in vaccine delivery: uncancelled extra appointments

 In school choice, the reason universal enrollment systems that give each child one assignment are so desirable is that if children are accepted by multiple schools, it often takes time (e.g. the first week of the school term) to sort out which children are going where, and to free up the unclaimed spaces.

The same thing is happening with decentralized appointments for Covid vaccines. The WSJ has the story:

Got Your Covid-19 Vaccine? Now Cancel Your Extra Appointments.  Pharmacies and community clinics say uncanceled appointments lead to no-shows, adding to their already heavy workload   By Jaewon Kang and Sharon Terlep

"Pharmacies and health officials are making a plea to Americans who received their Covid-19 vaccines: Cancel the other shots you booked.

"As vaccine eligibility expands and more places offer shots, many people are signing up for multiple appointments and not backing out of the ones they don’t need. The resulting influx of no-shows is forcing vaccine providers, from pharmacies to community clinics, to find last-minute replacements so doses aren’t wasted.

...

"Appointments remain tough to score in many parts of the country even though the overall supply of vaccines and the pace of inoculation are improving. Some people are making multiple bookings in hopes of getting vaccinated sooner or sometimes because they don’t receive or see confirmation emails, according to pharmacies and community vaccination sites. Others receive shots at pop-up vaccination events before scheduled appointments and don’t notify providers.

"The U.S. lacks a concrete system of tracking wasted doses. Generally, local and state officials say that demand is high enough that no-shows aren’t leading to tossed vaccines, though vaccine providers say they sometimes fail to find takers for all the doses they have thawed in time to use them all safely."

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Previous post:

Monday, February 15, 2021

Monday, March 22, 2021

Elite public schools move away from exams

 Covid cancelled exams for many exam schools: will they stay exam free in the future?  Several cities are moving in that direction.

Here's NBC, on Boston Latin:

A golden ticket: Efforts to diversify Boston's elite high schools spur hope and outrage. Exam schools loom large as symbols of opportunity and inequality in American public schools. Now, the nation's twin crises are shaking them to their core.  By Melissa Bailey, The Hechinger Report


Here's SF Chronicle on Lowell High School:

S.F. school board strips Lowell High of its merit-based admissions system  by Jill Tucker

"the San Francisco Board of Education voted 5-2 to use the same lottery-based system to assign students to Lowell High as other district high schools instead of maintaining the previous system that used test scores and grades."


Here's the NY Times on gifted programs for the youngest children:

N.Y.C. schools will replace the gifted and talented admissions exam with a lottery this year. By Eliza Shapiro

Tuesday, January 19, 2021

School choice under discussion in Vienna (video, in English and German)

 On Wednesday I spoke about school choice in Vienna.  (Here's the prospectus.)The video is below. (I start speaking around minute 9:30, in English, for 30 minutes, and the subsequent talk and discussion are in German.)


 
(https://www.youtube.com/watch?v=eZgOM6-xdH8&feature=youtu.be)

My understanding is that there will now be some opportunity for the scholars in Vienna to study the current (local) school assignment system used in Vienna, in conjunction with the schools administration.

Tuesday, January 12, 2021

School choice in Vienna (public talk on January 13)

 I'll give a (Zoom) talk tomorrow in Vienna (talk in English, discussion in German...)  


livestream13.01.2021, 18:00WU matters. WU talks.

Type Lecture / discussion 

LanguageLecture in English, Discussion in German 

Organizer WU (Vienna University of Economics and Business) Marketing & Communications

The status quo and the need for reform

This event is organized by the Department of Strategy and Innovation.

When it comes to choosing the right elementary school, a number of factors besides the school’s location can play a role, including how likely it is to even get a place in the chosen school. For this reason, many parents plan their registration strategically. What are the current system’s weaknesses, and what possible approaches could be taken to fix them? Nobel laureate Alvin E. Roth gives us an insight into the design of the computer algorithms used to distribute kids to schools fairly in many cities around the world.

Lecture:

Alvin E. Roth, Winner of the Nobel Prize 2012, Professor of Economics, Stanford University

Anita Zednik, Assistant Professor, Institute for Markets and Strategy, WU

Discussion:

Christiane Spiel, University of Vienna

Christoph Wiederkehr, Executive City Councillor for Education, Youth, Integration and Transparency

Anita Zednik, Assistant Professor, Institute for Markets and Strategy, WU

Moderation:

Ben Greiner, Professor of Empirical Business Research, WU

LIVESTREAM

Wednesday, December 30, 2020

A hard (theoretical) look at school choice, in the AER by Chris Avery and Parag Pathak

 What are some of the difficulties that might hamper school choice from achieving educational equality (or at least substantially reducing inequality)?  Here's a model by Chris Avery and Parag Pathak.  The theoretical intuitions of top experts in college and school assignments are the sort of thing that can keep you awake at night.  In a sentence, if school choice narrows the quality gap between the best and worst municipal schools, it may also narrow the gap in housing prices, and higher housing prices at the low end may drive poorer families to move to other school districts, just as lower quality at the high end drives richer families to suburbs with excellent schools. ("White flight" has been the subject of many papers, so the issue being raised here is that an improvement at the low end of school quality may also raise prices of less expensive housing and drive out poorer residents.)

The Distributional Consequences of Public School Choice  by Christopher Avery and Parag A. Pathak AMERICAN ECONOMIC REVIEW, VOL. 111, NO. 1, JANUARY 2021, (pp. 129-52)

"Abstract: School choice systems aspire to delink residential location and school assignments by allowing children to apply to schools outside of their neighborhood. However, choice programs also affect incentives to live in certain neighborhoods, and this feedback may undermine the goals of choice. We investigate this possibility by developing a model of public school and residential choice. School choice narrows the range between the highest and lowest quality schools compared to neighborhood assignment rules, and these changes in school quality are capitalized into equilibrium housing prices. This compressed distribution generates an ends-against-the-middle trade-off with school choice compared to neighborhood assignment. Paradoxically, even when choice results in improvement in the lowest-performing schools, the lowest type residents need not benefit."


"Our analysis contributes to a recent literature on school choice mechanisms, which has focused on the best way to assign pupils to schools given their residential location in a centralized assignment scheme. In particular, research has examined the best way to fine-tune socioeconomic or income-based criteria in choice systems. Cities have now experimented with complex school choice tie-breakers in an effort to achieve a stable balance (Kahlenberg 2003). 17 By incorporating feedback between residential and school choices, our model suggests that analysis of school assignment that does not account for possible residential resorting may lead to an incomplete understanding about the distributional consequences of school choice.

"A common rationale for school choice is to improve the quality of school options for disadvantaged students. But, our analysis shows that feedback from residential choice can undercut this approach, for if a school choice plan succeeds in narrowing the range between the lowest and highest quality schools, that change should compress the distribution of house prices in that town, thereby providing incentives for the lowest and highest types to exit from the town’s public schools. This intuition extends to the idealized case of a symmetric model of many towns and partisans, where each town adopts school choice and all schools within a given town have the same quality. Although there is an equilibrium in this idealized model where schools in all towns have the same quality, this equilibrium would likely be unstable, and instead we would expect to observe an equilibrium with differentiation of school qualities and housing prices across towns. That is, the within-town diversity observed in equilibrium under neighborhood assignment could be replicated in cross-town diversity under school choice.

A broader implication of our model is that systemic changes beyond the details of the school assignment system may be necessary to reduce inequalities in educational opportunities."

Monday, December 14, 2020

Designing centralized marketplaces that work gracefully with pre-existing decentralized ones, in Management Science, by Benjamin Roth and Ran Shorrer

 In Management Science (online ahead of print):

Making Marketplaces Safe: Dominant Individual Rationality and Applications to Market Design

 Benjamin N. Roth , Ran I. Shorrer 

Published Online:8 Dec 2020 https://doi.org/10.1287/mnsc.2020.3643

Abstract: Often market designers cannot force agents to join a marketplace rather than using pre-existing institutions. We propose a new desideratum for marketplace design that guarantees the safety of participation: dominant individual rationality (DIR). A marketplace is DIR if every pre-existing strategy is weakly dominated by some strategy within the marketplace. We study applications to the design of labor markets and the sharing economy. We also provide a general construction to achieve approximate DIR across a wide range of marketplace designs.


Introduction: "Many marketplaces operate in a broader economic environment, and often participants cannot be forced to use a marketplace rather than the pre-existing institutions it was meant to displace. For instance, although most hospitals and residents use the clearinghouse known as the National Residency Matching Program (NRMP) to coordinate job offers, there is no legal barrier that prevents members of either side of the market from finding matches outside of the clearinghouse.1 In school choice, charter schools sometimes opt not to participate in clearinghouses, instead recruiting students in a decentralized manner. In the private sector, marketplaces that comprise the gig and sharing economies demonstrate the primacy of attracting participants who have many outside alternatives. In each of these settings marketplaces are actively engaging with the challenge of recruitment. In other words, these are marketplaces in which participation is not always safe.

...

"A designer may introduce a mediator (alternatively referred to as a marketplace), to which players may delegate their decision rights (i.e., participate in the marketplace). The mediator comprises a message space and a mapping from messages to outcomes (strategy profiles for the delegators). Players who delegate their decision rights select a message to send to the mediator, who then acts on their behalf according to the outcome mapping, as a function of the whole set of messages it receives. The mediator is voluntary in the sense that players may choose one of their original (outside) actions instead of sending it a message. And the mediator is restricted to condition the actions of participants only on the messages of other participants and not on the outside actions of nonparticipants.

"This framework highlights the endogeneity of the individual rationality constraint with respect to both the set of players who sign away their decision rights and the actions they take. We show by example that mediators that satisfy attractive criteria such as incentive compatibility and efficiency assuming that everyone participates may no longer do so in equilibria with partial participation. This motivates the search for mediators that can guarantee the safety of participation. In Section 3 we present our key desideratum: dominant individual rationality (DIR)."

Wednesday, December 9, 2020

Top trading cycles (and recollections of New Orleans), in AER:Insights, by Abdulkadiroğlu, Che, Pathak, Roth and Tercieux

A decade ago I was part of the team that designed the new school choice system for the New Orleans Recovery School District.  On the District side, the effort was led by Gabriela (Gaby) Fighetti. The design team was organized by the (then) Institute for Innovation in Public School Choice (IIPSC), led by Neil Dorosin. The heavy lifting on the design was done by Atila Abdulkadiroğlu and Parag Pathak.  Until the district expanded and developed more complex requirements for expressing priorities (and we had to switch to a deferred acceptance algorithm) the design was based on a top trading cycles (TTC) mechanism. It was the first time I know of that TTC was adopted and deployed in a widely used market design. It came to be called OneApp (since it replaced the old system of applications to each school with one application followed by the matching algorithm).

Some of the data from that system make their way into this new (primarily theory) paper, about some of the distinctive virtues of top trading cycles. The paper itself is a merged effort between the New Orleans design team, and work on TTC initiated separately by various combinations of Che, Tercieux and Abdulkadiroğlu.

Efficiency, Justified Envy, and Incentives in Priority-Based Matching

By Atila Abdulkadiroğlu, Yeon-Koo Che, Parag A. Pathak, Alvin E. Roth and Olivier Tercieux, 

American Economic Review: Insights, December, 2020, 2, (4), 425–442.

Abstract: Top Trading cycles (TTC) is Pareto efficient and strategy-proof in priority-based matching, but so are other mechanisms including serial dictatorship. We show that TTC minimizes justified envy among all Pareto-efficient and strategy-proof mechanisms in one-to-one matching. In many-to-one matching, TTC admits less justified envy than serial dictatorship in an average sense. Empirical evidence from New Orleans OneApp and Boston Public Schools shows that TTC has significantly less justified envy than serial dictatorship. 

The first footnote of the paper suggests something of it's long history, and says in part:

"This paper supersedes “The Role of Priorities in Assigning Indivisible Objects: A Characterization of Top Trading Cycles,” cited by others as Abdulkadiroglu, Atila, and ˇ Yeon-Koo Che (2010) or Abdulkadiroglu, Atila, ˇ Yeon-Koo Che, and Olivier Tercieux (2010), and “Minimizing Justified Envy in School Choice: The Design of New Orleans’ OneApp” (2017) by Abdulkadiroglu, Atila, ˇ Yeon-Koo Che, Parag A. Pathak, Alvin E. Roth, and Olivier Tercieux. Roth is a member of the scientific advisory board of the Institute for Innovation in Public School Choice (IIPSC). IIPSC was involved in designing OneApp in New Orleans. Abdulkadiroglu, Pathak, and Roth also advised Boston Public Schools and New York City’s Department of Education on designing their student assignment systems, discussed herein. This article does not represent the views of the New Orleans Recovery School District or any other school district."

And here's a paragraph that offers a different kind of historical context:

"In 2011–2012, the New Orleans Recovery School District pioneered a unified enrollment process called OneApp, integrating admissions to all types of schools under a single offer system. Officials identified three major priority groups: sibling, applying from a closing school, and geography. The discussion about mechanism centered on the trade-off between efficiency and eliminating justified envy, and eventually TTC was selected based on the desire for “as many students as possible to get into their top choice school” (New Orleans Recovery School District 2012a). Vanacore (2011) and Vanacore (2012) provide additional details."


In conclusion:

"In the field, there is growing momentum for DA over TTC (see Abdulkadiroglu 2013 and Pathak 2017). This trend may be driven by a first-mover advantage of DA and its use in other contexts. New York City and Boston adopted DA in 2003 and 2005, and DA is widely used in residency matching (Roth and Peranson 1999). In 2013, New Orleans also switched from TTC to DA. One of the most important reasons for this switch involved challenges in explaining how TTC handles priorities.  Under DA, officials could explain that an applicant did not obtain an assignment at a higher ranked seat because another applicant with higher priority was assigned to that seat. At the time of the change, a clear explanation of how TTC reflects priorities was not available.

"It remains to be seen whether TTC will be used in the field again. But policymakers cannot ignore efficiency, which TTC delivers but DA does not. For this reason, TTC should remain a serious policy option. Our formal results may make it easier to explain how TTC incorporates priorities. It’s possible that TTC would have been chosen in some settings with knowledge of this result, and at the very least, advocates now have a new argument in its favor."

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Some long ago posts on school choice in New Orleans:


Saturday, November 19, 2011

Thursday, February 2, 2012

Tuesday, February 7, 2012

Sunday, May 12, 2013

Looking back at the first year of New Orleans' One App school choice system


Tuesday, October 1, 2013

Wednesday, February 11, 2015

Tuesday, August 18, 2015

A look back at school choice in New Orleans

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Principal Investigator(s):  r Principal Investigator(s) Atila Abdulkadiroglu, Duke University; Yeon-Koo Che, Columbia University; Parag Pathak, MIT; Alvin Roth, Stanford University; Olivier Tercieux, Paris School of Economics
 

Tuesday, September 1, 2020

Matching inequality and strategic behavior under the Boston mechanism: Evidence from China's college admissions by Wu and Zhong

 Here's a paper that analyses the immediate acceptance ("Boston") algorithm that was in use in China's college admissions system in many provinces, in 2003.

Matching inequality and strategic behavior under the Boston mechanism: Evidence from China's college admissions

by BinzhenWu and Xiaohan Zhong

Games and Economic Behavior, Volume 123, September 2020, Pages 1-21,  https://doi.org/10.1016/j.geb.2020.05.007


Abstract: We examine matching inequality in students' matching outcomes for the Boston Mechanism in a large matching system, by measuring the degree of mismatch for each student. We link a student's mismatch with her reporting behavior of the first choice on her preference list to explore the reasons for matching inequality. Using administrative data from college admissions in China, we find significant gender differences, rural-urban gaps, and ethnic gaps in mismatching and first-choice behavior. These demographic differences exhibit various patterns and may be explained by risk aversion, information disadvantage, and minority-preferential admissions policies, respectively.

Thursday, August 27, 2020

School choice with common preferences and incomplete information admits a winner's curse, by Kloosterman and Troyan

 Suppose that schools have an intrinsic quality that would affect the preferences of all students if they knew it, but some students are better informed than others. Then, for uninformed students, there can be a kind of winner's curse associated with being accepted to a school: the fact that it had seats available suggests that it might not be high quality.  Kloosterman and Troyan propose mitigating this by giving each student a secure school for which he/she has high enough priority to be admitted regardless of others' preferences: " a secure school is one with enough seats for j and every student who has higher priority than j. "  When all students have the same ordinal preferences at every state of the world, then the deferred acceptance algorithm with students proposing continues to make it a dominant strategy for informed students to state their true preferences, and there is an equilibrium that avoids the winners curse in which each uninformed student lists their secure school as their first choice.

School choice with asymmetric information: Priority design and the curse of acceptance

by Andrew Kloosterman and Peter Troyan 
Theoretical Economics, Volume 15, Issue 3, July 2020, Pages: 1095-1133

Abstract: We generalize standard school choice models to allow for interdependent preferences and differentially informed students. We show that, in general, the commonly used deferred acceptance mechanism is no longer strategy‐proof, the outcome is not stable, and may make less informed students worse off. We attribute these results to a curse of acceptance. However, we also show that if priorities are designed appropriately, positive results are recovered: equilibrium strategies are simple, the outcome is stable, and less informed students are protected from the curse of acceptance. Our results have implications for the current debate over priority design in school choice.

...
"How do secure schools help the uninformed? The problem for them is the curse of acceptance, and a secure school allows for them to have a default option that they can get in every state. Hence, the curse is entirely eliminated by allowing them to expect to get average utility, rather than always being left with the worst schools in every state. Theorem 1 formalizes this intuition to all markets in the common ordinal preferences model."

Friday, July 24, 2020

Experiments on school choice: a survey by Hakimov and Kübler


Hakimov, R., Kübler, D. Experiments on centralized school choice and college admissions: a survey. Exp Econ (2020). https://doi.org/10.1007/s10683-020-09667-7

Abstract: The paper surveys the experimental literature on centralized matching markets, covering school choice and college admissions models. In the school choice model, one side of the market (schools) is not strategic, and rules (priorities) guide the acceptance decisions. The model covers applications such as school choice programs, centralized university admissions in many countries, and the centralized assignment of teachers to schools. In the college admissions model, both sides of the market are strategic. It applies to college and university admissions in countries where universities can select students, and centralized labor markets such as the assignment of doctors to hospitals. The survey discusses, among other things, the comparison of various centralized mechanisms, the optimality of participants’ strategies, learning by applicants and their behavioral biases, as well as the role of communication, information, and advice. The main experimental findings considered in the survey concern truth-telling and strategic manipulations by the agents, as well as the stability and efficiency of the matching outcome.


From the Conclusions:

"The purpose and style of experiments on school choice and college admissions has changed over time. Many of the early experiments were tests of the theory. Horse races between different school choice mechanisms were conducted. Recently, many studies have dealt with systematic biases in behavior that matter in matching markets, such as bounded rationality, biased self-assessments, etc. Moreover, recent work also focuses on the question of how the exact implementation of a mechanism, e.g., static versus dynamic, with or without advice, afects market outcomes. Thus, the matching literature has started to establish behavioral regularities that can be of interest for policy makers involved in market design and behavioral theorists."

Saturday, July 4, 2020

Stanford GSB highlights Akbarpour and van Dijk on the virtues of strategy-proof school choice


Here's an article on the Stanford GSB website, describing a paper by Mohammad Akbarpour and Winnie van Dijk:

How School Choice Systems Create Unfair Advantages
Lotteries for public school admissions unintentionally favor students who have the option to attend private institutions, a new study shows.
June 26, 2020|by Maggie Overfelt

And here's the paper that the article highlights:
School Choice with Unequal Outside Options
September 2018 Working Paper No. 3764
Students with identical valuations for public schools but unequal outside options have different opportunity costs of revealing their preferences. Consequently, manipulable mechanisms need not resolve conflicting preferences in a Pareto-improving manner. We show that when they do not, welfare improvements for students with outside options come at the expense of students without outside options. This result strengthens the argument that strategyproof mechanisms “level the playing field.” Our model predicts that students without outside options are more likely to strategize, consistent with recent findings in empirical studies of education markets.

Tuesday, May 12, 2020

Confusion in NYC high school wait lists

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

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

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

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

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

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

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

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

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

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

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

Here's what was known then...

"What are these waitlists, anyway?
"New York City students must apply to high school, listing up to 12 schools they want to attend. A complicated algorithm, developed by a Nobel prize-winning economist, then matches a student to one of their choices.
"That fundamental algorithm is not changing. But for the first time this year, any student who does not get into their first choice school will automatically be added to the waitlist of every single higher-ranked school they didn’t get into.
"Every school that has more applicants than seats will have a waitlist. It’s a similar model that the education department uses for pre-K, kindergarten, and middle schools — something education department officials said is an advantage."
**********
Here's a story from the time of the initial announcement:

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

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

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

Here's my August post:

Friday, August 16, 2019 

Thursday, April 9, 2020

Medical triage for Covid-19: if/when it comes to that, how should it be organized?

So far I haven't heard of any actual medical triage in the U.S. in which life-saving treatment for Covid-19 is rationed.  There has been a good deal of discussion of how to avoid this, and of the short supply of masks, gowns, sedatives for intubation, and health care personnel.  Much of that discussion  has focused on reallocating scarce resources to where they are needed (from where they are not so scarce (e.g. California Ventilators En Route to New York, Other States), so that rationing of e.g. ventilators doesn't become necessary.  But if the infection curve doesn't flatten enough, triage may well be coming, at least in some places. (Here's an up to date account of a hard hit rural hospital near New Orleans that hasn't yet had to triage, but might be getting close if nearby hospitals were to stop taking transfers of patients.)  

Already in Italy there was a period (maybe still) when patients over age 70 (and later over 65) were not being given ventilators because of an actual shortage of ventilators compared to the number of patients who needed them. So it makes sense that, along with the discussion of how to prevent the need for triage, there is an ongoing discussion of how to manage it, if  there comes a time and place where there aren't enough vents to go around. (I have already heard a somewhat related discussion in the U.S. about whether patients on vents should be resuscitated--given the small chance of recovery, and the exposure of health care workers to Covid-19 during a resuscitation attempt.)

As in discussions of repugnant transactions, discussing allocation of scarce resources provokes lots of debate about who should get what, and what kind of distinctions should and should not be made. 

Here are longish excerpts from several interesting contemporary accounts:

Here's an article in the March 23 New England Journal of Medicine:

by Ezekiel J. Emanuel, M.D., Ph.D., Govind Persad, J.D., Ph.D., Ross Upshur, M.D., Beatriz Thome, M.D., M.P.H., Ph.D., Michael Parker, Ph.D., Aaron Glickman, B.A., Cathy Zhang, B.A., Connor Boyle, B.A., Maxwell Smith, Ph.D., and James P. Phillips, M.D.

"Rationing is already here. In the United States, perhaps the earliest example was the near-immediate recognition that there were not enough high-filtration N-95 masks for health care workers, prompting contingency guidance on how to reuse masks designed for single use.2 Physicians in Italy have proposed directing crucial resources such as intensive care beds and ventilators to patients who can benefit most from treatment.3,4 Daegu, South Korea — home to most of that country’s Covid-19 cases — faced a hospital bed shortage, with some patients dying at home while awaiting admission.5 In the United Kingdom, protective gear requirements for health workers have been downgraded, causing condemnation among providers.6 The rapidly growing imbalance between supply and demand for medical resources in many countries presents an inherently normative question: How can medical resources be allocated fairly during a Covid-19 pandemic?
...
"According to the American Hospital Association, there were 5198 community hospitals and 209 federal hospitals in the United States in 2018. In the community hospitals, there were 792,417 beds, with 3532 emergency departments and 96,500 ICU beds, of which 23,000 were neonatal and 5100 pediatric, leaving just under 68,400 ICU beds of all types for the adult population.12 Other estimates of ICU bed capacity, which try to account for purported undercounting in the American Hospital Association data, show a total of 85,000 adult ICU beds of all types.13

"There are approximately 62,000 full-featured ventilators (the type needed to adequately treat the most severe complications of Covid-19) available in the United States.14 Approximately 10,000 to 20,000 more are estimated to be on call in our Strategic National Stockpile,15 and 98,000 ventilators that are not full-featured but can provide basic function in an emergency during crisis standards of care also exist.14 Supply limitations constrain the rapid production of more ventilators; manufacturers are unsure of how many they can make in the next year.16 However, in the Covid-19 pandemic, the limiting factor for ventilator use will most likely not be ventilators but healthy respiratory therapists and trained critical care staff to operate them safely over three shifts every day. In 2018, community hospitals employed about 76,000 full-time respiratory therapists,12 and there are about 512,000 critical care nurses — of which ICU nurses are a subset.17 California law requires one respiratory therapist for every four ventilated patients; thus, this number of respiratory therapists could care for a maximum of 100,000 patients daily (25,000 respiratory therapists per shift).
...
"Previous proposals for allocation of resources in pandemics and other settings of absolute scarcity, including our own prior research and analysis, converge on four fundamental values: maximizing the benefits produced by scarce resources, treating people equally, promoting and rewarding instrumental value, and giving priority to the worst off.24-29 Consensus exists that an individual person’s wealth should not determine who lives or dies.24-33 Although medical treatment in the United States outside pandemic contexts is often restricted to those able to pay, no proposal endorses ability-to-pay allocation in a pandemic.24-33
...
"These ethical values — maximizing benefits, treating equally, promoting and rewarding instrumental value, and giving priority to the worst off — yield six specific recommendations for allocating medical resources in the Covid-19 pandemic: maximize benefits; prioritize health workers; do not allocate on a first-come, first-served basis; be responsive to evidence; recognize research participation; and apply the same principles to all Covid-19 and non–Covid-19 patients."


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Here's a Washington Post story with a good summary of much of the discussion and disagreement about how different patients (and groups of patients) might be prioritized if ventilators have to be rationed:

By Ariana Eunjung Cha and Laurie McGinley April 7, 2020 

"Pregnant women would get extra priority “points” in most if not all plans, U.S. hospital officials and ethicists say. This is not controversial. There also has been some discussion about whether high-ranking politicians, police and other leaders should be considered critical workers at a time when the country is facing an unprecedented threat.
...
"Catholic groups have called on hospitals to treat pregnant women as two lives instead of one. AARP, formerly the American Association of Retired Persons, has decried age cutoffs for ventilator access in some plans. Last month, the Arc, a disability rights group, filed multiple complaints with the Department of Health and Human Services objecting to plans that disadvantage those with “severe or profound mental retardation” or dementia.
...
"Bioethicist Brendan Parent, who served on a New York state task force that developed a highly regarded framework for rationing, sees hospitals and states following two paths.

"One group takes a utilitarian view of doing “the greatest good for the greatest number,” giving preference to those with the best chance of surviving the longest. Others are more focused on ensuring social justice and ensuring vulnerable groups have an equal chance.
...
"UCLA’s plan goes to great lengths to avoid possible discrimination, stating that medical teams may not consider a long list of criteria for ventilator allocation including gender, disability, race, immigration status, personal relationship with hospital staff or “VIP status” — an important reminder given the medical center’s proximity to Hollywood.
...
"In UCLA’s plan, front-line health-care workers and administrators may be given priority access to lifesaving treatment, when their return to work means more people are likely to survive the crisis. If all the allocation criteria are applied and there’s still a shortage of medical resources, then care should be allocated on the basis of a lottery, the document says.
...
"One of the most striking differences among plans is how they deal with the elderly and disabled. Some have strict age cutoffs, or explicit criteria that disadvantage those with certain conditions.
...
"Using life expectancy or remaining life years can also be problematic for those with disabilities, civil rights groups say. The typical life expectancy for a person with Down syndrome, for example, is 60 years, as compared to about 78 years for someone without the condition.
...
"Inova’s Motew said ethical principles allow for prioritizing “some individuals who provide more lifesaving opportunities if they could live” — and that this could include “government leaders.” He compared it to military medicine, in which those who are in a position to go back to help win the war are treated first."

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And here are some thoughts on what we might learn about medical triage from considerations that come up in allocating school places among different populations for whom some positions are reserved.  The idea is that different groups of patients would have places reserved for them, through the kind of political process that reserves places in schools for different demographic groups, with priorities within groups, and ordering of reservations among groups. Once those issues are settled by some political process, the problem starts to look like school choice with affirmative action, and in the model proposed by these authors (who are well acquainted with school choice), deferred acceptance algorithms emerge:

Triage Protocol Design for Ventilator Rationing in a Pandemic:
A Proposal to Integrate Multiple Ethical Values through Reserves
Parag A. Pathak, Tayfun Sonmez, M. Utku Unver, M. Bumin Yenmez
April 2020

Abstract: In the wake of the Covid-19 pandemic, the rationing of medical resources has become a critical issue. Nearly all existing triage protocols are based on a priority point system, in which an explicit formula specifies the order in which the total supply of a particular resource, such as a ventilator, is to be rationed for eligible patients. A priority point system generates the same priority ranking to ration all the units. Triage protocols in some states (e.g. Michigan) prioritize frontline health workers giving heavier weight to the ethical principle of instrumental valuation. Others (e.g. New York) do not, reasoning that if medical workers obtain high enough priority, there is a risk that they obtain all units and none remain for the general community. This debate is particularly pressing given substantial Covid-19 related health risks for frontline medical workers. In this paper, we propose that medical resources be rationed through a reserve system. In a reserve system, ventilators are placed into multiple categories. Priorities guiding allocation of units can reflect different ethical values between these categories. For example, while a reserve category for essential personnel can emphasize the reciprocity and instrumental value, a reserve category for general community can give higher weight to the values of utility and distributive justice. A reserve system provides additional flexibility over a priority point system because it does not dictate a single priority order for the allocation of all units. It offers a middle-ground approach that balances competing objectives. However, this flexibility requires careful attention to implementation, most notably the processing order of reserve categories, given that transparency is essential for triage protocol design. In this paper, we describe our mathematical model of a reserve system, characterize its potential outcomes, and examine distributional implications of particular reserve systems. We also discuss several practical considerations with triage protocol design.

And from the conclusion:

"In our formal analysis, we characterize the entire class of reservation policies that satisfy three minimal principles though implementation of the deferred-acceptance algorithm. As such, we also provide a full characterization of affirmative action policies."
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There are of course other models of triage than school choice. In transplantation, there's a shortage of both deceased and living donors, to the extent that many people who need transplants will never get them. The allocation of deceased donor organs is handled not entirely differently than generalized school choice of a particularly dynamic sort (potential recipients of a deceased donor kidney that suddenly becomes available are categorized into groups, not just by blood and tissue types which have immediate feasibility implications, but also by age and by how difficult it will be to find them a feasible match, and prioritized within groups mostly by waiting time and health status, differently for different organs).  Living donors (almost all are donating a kidney) are much less regulated, and through kidney exchange are mostly allocated through an exchange system that is fairly blind to group membership, although the statistics that are collected pay attention to people in a variety of categories.  The point of kidney exchange of course is not just to allocate scarce resources, but to make them less scarce.  That is a goal to think about whenever triage becomes necessary, or starts to look like it might.

Sunday, March 22, 2020

School choice without the assumption of full-information equilibrium by Kapor, Neilson and Zimmerman

Forthcoming in the AER:

Heterogeneous Beliefs and School Choice Mechanisms By Adam J. Kapor and Christopher A. Neilson and Seth D. Zimmerman

Abstract: This paper studies how welfare outcomes in centralized school choice depend on the assignment mechanism when participants are not fully informed. Using a survey of school choice participants in a strategic setting, we show that beliefs about admissions chances differ from rational expectations values and predict choice behavior. To quantify the welfare costs of belief errors, we estimate a model of school choice that incorporates subjective beliefs. We evaluate the equilibrium effects of switching to a strategy-proof deferred acceptance algorithm, and of improving households’ belief accuracy. We find that a switch to truthful reporting in the DA mechanism offers welfare improvements over the baseline given the belief errors we observe in the data, but that an analyst who assumed families had accurate beliefs would have reached the opposite conclusion.
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see my earlier post:

Monday, January 28, 2019

Friday, March 6, 2020

Thomas Toch on school choice and the presidential campaigns



Toch: School Choice Is Here to Stay. But How to Make It Fair and Equitable for All Families? High-Tech Common-Enrollment System Can Help

"The leading Democratic presidential candidates — liberals Elizabeth Warren and Bernie Sanders, but also moderates Joe Biden and Pete Buttigieg — have derided publicly funded charter schools as a threat to traditional public schools. But charter schools and the new, more consumer-oriented public education landscape they represent are here to stay.
...
"In this climate, the policy question is not whether we should have public-sector choice. Instead, we should be asking how to make choice systems in public education efficient and fair for all families. One promising answer: common-enrollment systems that allow families to select traditional public schools or charters through a single, centralized selection process powered by algorithms that match as many students as possible to their top choices.
...
"But taking advantage of expanding public options traditionally meant navigating myriad application timelines and deadlines without information to make clear comparisons.

"It meant oversubscribed schools pulling names out of paper bags, families pitching tents on sidewalks — or paying others to camp out for them — to get to the front of waiting-list lines and schools cherry-picking applicants to get the most attractive students. It was a system favoring the well-educated, the wealthy and the well-connected.

"For schools, that system made planning almost impossible. Many students were admitted to multiple schools but didn’t let schools know their plans, causing thousands of waitlisted students to change schools even after the start of classes, leaving administrators guessing about revenue and staffing, and disrupting instruction.

"But in recent years, the District of Columbia, Denver, New Orleans and a handful of other cities have launched a new way of matching students to schools that addresses these problems."
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In the manner of journalists with space limitations, Toch goes on to attribute these advances to "Alvin Roth and colleagues."  Of course, prominent among those colleagues are the two leaders in the modern school choice revolution, Atila Abdulkadiroglu and Parag Pathak.

Monday, March 2, 2020

NSF 70th Anniversary Symposium--the video

I recently attended the celebration of the 70th anniversary of the National Science Foundation, a two-day symposium on Feb. 6-7, 2020. Below is a video of the first day, in which I took part in a session called Science Breakthroughs, which begins at hour 3:45 and goes for an hour. Hear a moderated discussion ranging back and forth over gravity waves, black holes, thermal vents, nanotechnology, and market design (school choice, kidney exchange, repugnant transactions and the fact that both markets and bans on markets require social support to work well).




Science Breakthroughs
Panel featuring NSF-funded science breakthroughs from the last decade. The topics covered in this panel will feature a mix of major breakthroughs, as well as research that has led to significant impacts on society. In addition, the panelists will be a diverse set of researchers, including those earlier in their careers.

Moderator: Amy Harmon, Correspondent, New York Times
Panelists: Jennifer Dionne, 2019 Waterman Award recipient & Associate Professor, Stanford University
Shep Doeleman, 2019 Breakthrough Prize & NSF Diamond Award recipient & Director, EHT at Harvard-Smithsonian Center for Astrophysics
Margaret Leinen, Director, Scripps Institute & Vice Chancellor & Dean, Marine Sciences
Nergis Mavalvala, Professor & Associate Head, Department of Physics, MIT
Alvin Roth, Nobel Prize in Economics 2012 & Professor of Economics, Stanford University