Shengwu Li
@ShengwuLi
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Economist. @Harvard. Mechanism design, behavioral theory.
Joined November 2016
Many families have vindictive relatives. My relatives just happen to control a small authoritarian government. šøš¬ š§µ.
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While a PhD student at Stanford, I had to attend an interview to check whether I could teach in English. This was because my BA was from a foreign university; the University of Oxford.
Today I get to pay $300 to take a 3-hour English test in order to be eligible to stay in the country where I am employed to teach English language courses at an English language institution, a prerequisite for which was the PhD I earned at an English language university.
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Daron Acemoglu already has a social media account for economics posting. Itās called Econometrica.
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Breaking: My father, the youngest son of Lee Kuan Yew, has received refugee protections under the 1951 Geneva Convention. This grant of asylum follows a long campaign of persecution from the Singapore government.
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I am shocked, shocked to hear that the āinfinite monkey theoremā smuggles in the assumption that there are infinitely many monkeys.
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Tenured. Now that it's no longer tempting fate, let me say this: Be kind to yourself. It's easy on the tenure track to work to the point of negative marginal return. Focused work is hard. If you can work on a proof for four real hours in a day, that is a good day.
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Look, Iām no economist but arenāt questions like āhow do we incentivize companies to produce enough rapid tests to meet demand?ā the sort of thing yāall are supposed to be helping with?.
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It took me 30 seconds to fact-check this claim in the Chomsky op-ed.
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It has been 5 years since I left home, because of a political prosecution by the Singapore government. Friends often ask me if it's safe to return.
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In the past, I've had students call my problem sets "emotionally trying". (These are for 2nd-year PhD game theory.) This year I'm going to explain myself and set clearer expectations.
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It is not from the benevolence of the butcher, the brewer, or the bakerā¦
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Well, this went rapidly from āway outside economistsā expertiseā to nuclear game theory plus macroeconomic forecasting. Stand back political scientists, this is officially our lane.
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This time, the Nobel committee skipped the computer scientist and gave the prize directly to the machine.
The best Nobel prize ever! Congratulations to @DAcemogluMIT, @baselinescene, and my Harris colleague Jim Robinson!
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āBut I donāt see what auction theory has to do with my life!ā, they tweet, over airwaves allocated by auction, while a swarm of advertising algorithms bid for their eyeballs. š¤.
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Preparing to talk to students about research advice / hidden curriculum. Here are guesstimated base rates for converting ideas to papers.
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Giving good talks is a core skill for academics. It's learnable!. Here's how I approach mine.
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10 thinkers who changed how I see the world:. 1. Newton (invented calculus). 10. Leibniz (invented binary).
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As someone who did a bit of college debate, I always knew we were weird. But college students should be able to voice ordinary political disagreement without fearing social sanctions. And Iām surprised by academics who donāt regard this norm as worth defending.
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Phew. GPT4 still can't solve PhD-level mechanism design problem sets. As we all know, this is the ineffable quality that separates humans from machines.
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Thoughts on learning to "fail fast" in research. When you have a new idea, and the project is worthwhile only if P, then you need to check P first, not last. Examples: 1. You can only establish causality with a certain kind of data. š§µ.
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Today a polymath public intellectual wandered into my domain of expertise (game theory), and I discovered they were just smoke and mirrors. Ah, well.
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Ok here are my go-to papers for making small talk with smart non-econs. (Yes, I am exactly as uncool as maintaining this list would imply.).
what paper (not your own, maybe not even in your own area) can you not stop telling people about?.
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My aunt, Lee Wei Ling, passed away on Oct 9. When I was a child, she recruited my brother and me as lab subjects for a brain imaging study. Ever the scientist. Her funeral is today, in Singapore. It pains me that I cannot be there to say goodbye.
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Thereās an econ paper by a Harvard law professor that uses game theory to deny that the Japanese military held sex slaves during WW2. Yes, it literally makes that claim. #EconTwitter.
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Why unrealistic theories?. Most econ students go through a phase of thinking that more 'realistic' theories are automatically better. But here are some good reasons for unrealism.
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Having angered the humanities-econs, let me now anger their complement. I think that every PhD student should learn about the history of economic thought. Either by reading primary texts or by reading the work of relevant historians.
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Bold new theories of inflation, ignored by the academic mainstream:. #1. Inflation is caused by the Kierkegaardian sin of despair, the āsickness unto deathā at the heart of the human condition.
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A lightboard-style setup without the lightboard. All you need is an ipad, a stylus, and OBS. Thanks @rithvikra0 for the idea! #EconTwitter
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Reminder that research potential is extremely hard to measure at the PhD admissions stage, and many great researchers come from outside ātopā departments.
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Imagine how much more he would publish if he wasnāt named Acemoglu.
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Akerlof received the best rejection letters for the market for lemons.
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I've put together presentation advice for econ theory talks. It's coming that time of year when many young theorists rapidly learn to present papers, so I thought this might be useful.
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I didnāt take real analysis as an undergrad. (Oxford PPE students canāt take math courses.) And the Harvard econ PhD rejected me twice. I took real analysis as a 2nd year grad student at Stanford. It worked out fine.
Normalize taking undergrad math classes in grad school when you didn't have the opportunity to take them in undergrad.
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Wait, so is Ginoās defense that she manages her RAs so poorly that multiple teams committed fraud without her noticing, and she doesnāt even remember their names?
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Kahneman and Tversky proposed a theory of choice that was psychologically plausible and mathematically precise. They showed that a better kind of theory was possible. Rest in peace, Danny Kahneman.
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I think economists should read Smith, Marx, and Keynesā¦. ā¦and Mill and Kant and Aristotle and Chaucer and Dostoyevsky. And they should do this, not because they are economists, but because they are human beings. Hence, none appear on my syllabuses.
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I now reside in Cambridge, MA, and have a green card. It's gutting to be unable to return home, and to watch from afar as Singapore slides steadily further into authoritarianism. I'm grateful for the support and sympathy from my friends and my colleagues at @Harvard.
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I donāt care if itās real analysis in particular. But one has to be deeply incurious not to take a proof-based math course before starting an econ PhD.
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Suggest rebranding āall errors remain are ownā with āall errors are the fault of an anonymous RA, to whom I give no credit and whose name I cannot recallā.
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An open offer for the fall semester: If youāre teaching a class for PhD students and one of my papers is on your syllabus, I would be happy to give a guest lecture. Get in touch!.
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What horrible luck, that a famous dishonesty researcher would have four separate RAs that falsified data. Really, what are the odds? š^4?.
āThe fraud isnāt my fault because my grad students, who werenāt coauthors, did literally all of the workā is quite a take.
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True Cambridge MA elitism is not about arguing whether Extension School is āreally Harvardā. Itās about arguing about whether the Media Lab is really MIT.
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Econ perspective: People make choices to satisfy their preferences. Psych perspective: People adapt their preferences to justify their choices. Here's a theory that combines them. (A new working paper joint with Erik Eyster and Sarah Ridout.) ļæ½
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I donated $1,000 to support @DataColadaās defense against Ginoās ridiculous lawsuit. Believers in open science must stand together. Frankly, @HarvardHBS should step up and cover their costs. Leif, Joe, and Uri have done them an immeasurable service.
Be a part of the change you wish to see in the world:.Donate to help support the legal expenses of Data Colada. They're being sued by Prof Gino after posting careful, meticulous blog posts raising concerns about data integrity in 4 papers. Donate here:
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My father is applying for a permit to demolish his father Lee Kuan Yewās house at 38 Oxley Road.
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This JEP paper on game theory makes explicit a lot of what (I hope) econ grad students implicitly learn. Iām going to start assigning it as reading.
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As a behavioral economist, I'm especially irked by the "neoclassical econ has false assumptions" crowd. Even though I (obviously) think that the classical model has important limitations. I feel about them how a Roman reformer would have felt about the vandals.
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If itās hard for grad students to transition from coursework to idea generation, what can we do about it?. One idea: faculty could hand students a starter project. That is, a well-formed open question that can likely be answered via standard methods.š§µ.
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When so many ask, āHow is this economics?ā, itās nice when the QJE answers, āyes this is economics.ā. Economics, like early hominids, thrives by aggressively expanding its territory.
Recently accepted by #QJE, āThe Ant and the Grasshopper: Seasonality and the Invention of Agriculture,ā by Andrea Matranga (@andreamatranga):
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Nice one, @ZachWeiner. Actually, it's standard advice for PhD students that one should not worry about getting perfect grades, because it's better to spend time on research.
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Let me offer a defense of complex models for everyday economic situations. Of course workers aren't literally taking the integral. They're behaving based on a mixture of heuristics, common sense, and folk wisdom. š§µ.
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The NYPD thinks that the OUP Very Short Introductions are how-to books. In that spirit, here are some reading recommendations, in alphabetical order:
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The list of Basic Presentation Habits That Make Me Judge You. Thanks @jmwooldridge and @KhoaVuUmn for getting the ball rolling!. š§µ 1/219.
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How can you know anything about ornithology, given that you are not a bird?.
One of the more fascinating phenomena is people who think they understand economics that have never built a two-sided marketplace, coded a financial instrument, issued a digital currency, started a company, managed a cap table, met a payroll, or created a single job.
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Hot take: The predoc system exists because of modern applied micro. Research via ālabsā has increased the amount of delegatable busywork. In the hard sciences this work is done by PhD students. But because econ PhDs are on a pure mentorship model, this leads to predocs.
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The odd hedonic thing about academia: When you get an R&R, you don't celebrate, because you don't want to jinx it. And when a paper is accepted, you don't celebrate, because most uncertainty resolved at the R&R stage. Don't do this! Celebrate every milestone. š¾.
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No.
Game theory provides a complete replacement for traditional moral philosophy because it a) provides a rigorous theory of what you ought to do, and b) cleanly distinguishes between moral (cooperative) and immoral (uncooperative) ways of behaving.
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My brilliant friend Mohammad @akbarpour_ just got voted tenure at Stanford GSB. On the job market, when interviewers asked about his research agenda, Mohammad would reply, āIf you want to make God laugh, tell him your plans.ā.
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Let me be clear to any corporation that hasnāt brought their prices back down even as inflation has come down: Itās time to stop the price gouging. Give American consumers a break.
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Game theory has all these nice epistemic tripwires that catch charlatans. (Definition of a dominant strategy, of a zero-sum game, the folk theorem, etc etc).
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Plot hole in War of the Worlds: What civilization develops space travel and terrifying sci-fi weapons, but neglects basic defences against respiratory coronaviruses?.
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Siri whatās an exogenous shock to trade flows?.
The Suez Canal, one of the busiest waterways in the world, has been blocked by a giant container ship that got stuck. You can see other ships piling up behind it. by @roberttuttle & @JavierBlas
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When a hostile authoritarian government says they want to 'question' you, it is clear what that means. For the prime minister of Singapore, it's 'rule of law' for thee but not for me.
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How to tell when a reporter doesnāt know anything about economics publications.
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Classical physics is a hell of a drug. It has no theory of particles, no account of cosmic inflation, and its models all presume the existence of ācosmic spheresā made of earth, air, fire, water, and an āƦtherā that perfectly resists all motion.
Neoclassical economics is a hell of a drug. It has no theory of prices, no account of inflation, and its models all presume the existence of a perfectly rational "homo economicus" who is a "utility maximizer" with perfect information. 1/
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For anyone who wonders today if anything they do matters, hereās a paragraph by CS Lewis that helps me. Itās part of a sermon at Oxford in 1939, titled āLearning in Wartimeā.
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Conjecture: One reason for the willingness of public health officials to tell noble lies is a technocratic belief that laypeople are not able to deal with trade-offs and uncertainty.
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A lesson from auction theory: If you have the most extreme signal about the value of the prize, then everyone else knows something that you donāt. This suggests that you should adjust accordingly.
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It's about the system. Research fraud thrives when a field rewards single 'surprising' findings and there are low incentives for replication. The problem is not enough formal theory.
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New identification strategy just dropped. Just compute sample hazard rates, and then.
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Congratulations to Stanford GSB, that just voted to make Mohammad @akbarpour_ a full professor!. Attached is a photo of a class project we wrote a decade ago, and a stylized model of Mohammad that abstracts away from facial hair.
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š„³ Conditionally accepted at Econometrica: Algorithmic Mechanism Design with Investment. (w Mohammad Akbarpour,@skominers, Kevin Li, and Paul Milgrom.). VCG mechanisms aren't always feasibleāmany real-world allocation problems are NP-hard, so we can't compute optimal allocations.
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Shadow prices.
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Caveat: Academic prizes donāt make for good research incentives. Nonetheless, Iām delighted to be in this yearās cohort of Sloan Fellows, with @instrumenthull @alexoimas @TobiasSalz (and others not on twitter).
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Standardized tests do not measure understanding directly. They measure behavior that is a signal of understanding; and is costly/hard for humans to imitate without it. ChatGPT is changing the cost function.
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In the face of unprecedented logistical challenges during WWII, mathematicians intervened to help the allied war effort. This was the birth of the field of operations research. Iām glad that George Dantzig, Freeman Dyson, and Ken Arrow did not stay in ātheir lanesā.
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The court case is technically over. However, I assess that there's a substantial risk that my uncle, the Prime Minister, would find an excuse to imprison me were I to return to Singapore. He likes to relitigate old disputes.
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Wow. This article is how you do journalism on scientific misconduct.
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This. Please. Instead of predocs, let's have replication police.
Surprised journals don't hire teams of RAs to replicate papers before acceptance. It would honestly be remarkable training for grad school.
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My advice for coauthorships is to start your PhD the same year, do the RESTUD tour together, and get voted to full prof in same week.
Congratulations to Stanford GSB, that just voted to make Mohammad @akbarpour_ a full professor!. Attached is a photo of a class project we wrote a decade ago, and a stylized model of Mohammad that abstracts away from facial hair.
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Rest in peace Daniel Ellsberg. May we all have such moral courage when destiny comes knocking. Ellsbergās story gave me hope in dark times. In 2017, I spoke truth to the authoritarian government in Singapore and lost a home.
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How to email your professor:. 1. Find your profās email address and prior belief. 2. Compute your utility as a function of profās posterior belief. 3. Concavify. 4. Profit.
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One of the beautiful things about doing theory is how much of the work can be done on a walk outside.
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Elizabeth Warren must be pleased to hear that oil companies have become less greedy.
Oil plunges below $70 a barrel as new Covid variant roils markets
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Every grad student eventually learns what their advisor can (and can't) do. And also the particular tricks in 'managing up' for that person. I'm writing a user's guide, for students who want to ask me for advice. Has anyone else tried doing the same?.
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It's a good thing that economists don't spend much time arguing about what past economists 'really' meant. Theories should be evaluated against evidence. They don't get special status by venerable ancestry.
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Itās the season to post job-market papers. 1. JMPs are working papers. As with all working papers, they should be open to public discussion and critique. 2. Thereās every reason to be civil and generous when discussing JMPs, especially since the author is stressed and busy.
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Calculus is one of humanity's most important discoveries. It's so good we invented it twice. Modern AIs run on a glorified algorithm for chain rule.
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Itās the season when the academic commentariat decides that true academic achievement is only marked by blood money from a Swedish arms dealer, rather than funds from the Swedish central bank.
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Let me explain this claim, as if to an undergrad, an aspiring economist who has not yet taken a math course with real proofs. š§µ.
I donāt care if itās real analysis in particular. But one has to be deeply incurious not to take a proof-based math course before starting an econ PhD.
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Defining notation for a theory paper is halfway between making up a language and choosing an opening in chess. Small early choices affect what moves are available later.
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Apparently, someone falsely put my name to an open letter from Harvard Faculty and Staff for Justice in Palestine (HFSJP). This is the same group that recently circulated an antisemitic cartoon. 1. I have not signed that letter. 2. Today I learned that HFSJP exists.
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It seems unfair that philosophers tell economists that weāre paid too much. Do we go around telling philosophers that their groundsā grounds are not grounded?.
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