IO economist
@FTC
. PhD
@NUEconomics
. Information econ, antitrust. Foodie. Personal opinions only. If you say things unequivocally, I don't trust you.
How I published no papers in my first 3 years of PhD:
- My mother got diagnosed with Parkinson’s and I became a primary caregiver;
- My husband got unemployed and I had to work extra;
Let’s stop considering quantity as the ultimate goal and start treating people as humans.
~I HAVE A NEW PAPER~
It's about how some consumers are rich & some are poor & how this changes the causes/effects of market power. I develop a *simple* partial equilibrium framework to do {your favorite IO analysis} with (sorely needed) consideration for consumer inequality.
🚨ATTENTION JMCs🚨
There are 5 days left to apply to the FTC! In addition to doing awesome work to protect consumers from unfair business practices, the FTC is the premier gov't agency for young economists to do research.
Some examples🧵:
IO econs are advocating for *more* macro level studies ("has concentration increased across many markets?") while *also* pushing against using IO (antitrust) tools to fight macro issues.
I agree with both & do not think there is a tension between these two things. (1/8)
I got the lowest grade in a first year macro exam. Halfway through, I realized I couldn't make progress on *any* of the questions. Drew a cartoon of a lobster waving a flag saying "I surrender" instead. I'm not even good at drawing
Got lowest grade in Ariel Rubenstein’s micro class, went to chat about it. He picks up and stares at my exam book, back to me, back to the exam. Him: “didn’t study math, did you? And you won’t pursue theory?” Me: “no”. Him: “you’re fine then”, closes book, no further explanation.
While I agree all three are good practices, I still find it hilarious that the RAND Journal of Economics explicitly calls out only these very specific writing faux pas, especially since there are so many others in most papers
Non-economists: you econs and your models are so unrealistic. There's no way you could reduce the complexities of the world down to a few variables
Economist: Allow me to introduce you to my friend $\varepsilon$
Had a great time talking to
@NUEconomics
undergrads today about the practice of antitrust! Shout out to the one guy who slept thru my talk but woke up for the Q&A to ask several questions about... investment banking?
My experience has been quite different...
2010 status job: tenure-track at MIT
2015 status job: tenure-track at top 20
2023 status job: tenure-track, literally anywhere
When I graduated college in 2010 I saw the status job offer shift from Goldman Sachs to Google. What's going to be the hot new industry for recent grads now if tech is passé?
I just spent last week at Northwestern/Kellogg. Maybe it's an outlier (where else are there hundreds of econs in one state of the art building?) but the place was *electric* and I miss it so much. The in-person amenities and network effects are absolutely priceless.
Biz school faculty, looking for some Friday feedback.
*Would you join* a new university that was designed to be WFH similar to Airbnb's new policy?
Faculty on-campus teaching 1-2 months, otherwise quarterly in-person meetups. Students on campus.
FTC Micro Conference 2022 is in the books! Was a great conference that brought together the antitrust and broader academic communities (these are not that distinct from one another)! A quick synopsis of the papers I saw (missed a couple):
The Gandhi et al. (2023) approach to zero empirical shares is so intuitive & I don't know why it isn't more widely adopted.
Like, of course s_ij = 0 because true choice probs are positive but small and we only observe finite demand draws!
🚨 NEW DRAFT 🚨 of “Algorithmic Competition, with Humans” posted! This is a pretty major revision (a v2.0, not a v1.1) responsive to some great feedback I’ve gotten, though the bones of the paper remain the same. 🧵
My (former) JMP started as an empirical paper.
I think it will work better as a metrics paper...
...if I can *slightly* generalize my main theorem.
Once every 3 months, on a slow Friday, I try. Been doing this for four years.
It's the most masochistic ritual.
After 3 years, we have finally submitted "Dynamic Regulation with Firm Linkages"! Already posted a summary thread before, but the gist: linking scrutiny past pollution offenders with scrutiny of their co-owned plants is *quite* efficient!
We maintain a log of publications at the FTC.
I count *72* publications by FTC economists since 2020. Including, depending on your definition (mine was pretty strict), 12 top 5/top field/equivalent.
And an amazing pipeline!
And a great seminar series:
Data linking individuals' characteristics to their choices aids the identification of demand, with no need for “BLP instruments.” Own/cross-price elasticities are often identified even when non-price choice characteristics are endogenous and uninstrumented
The
@FTC
Microeconomics Conference 2023 agenda is out! Looking forward to seeing papers on platforms, privacy, labor market power, innovation, and more!
I don't really know what price theory is. There's models, which are bundles of assumptions, and other models, which are different bundles of assumptions, and then there are the predictions that follow.
Whelp, I just set the high water mark for meanest referee report I've ever received.
On one hand: if you really think the paper is far from where it needs to be, this is certainly a way to convey that.
On the other...
FTC's Bureau of Economics hired 10 PhD economists last year, seven this fiscal year, and has openings for 13 more, director Aviv Nevo says on an ABA webinar.
🚨NEW PAPER🚨 w/ Nicholas Vreugdenhil: “Dynamic Regulation with Firm Linkages”
In this paper, we empirically measure the effectiveness of a dynamic linked regulation regime.
What is dynamic linked regulation, and why is it useful? Read on!🧵
We've seen precious few "anatomy of a cartel" papers, and when we do, they are horizontal: bidding rings, trade assns, coordination via intermediary. This one involved a supplier. I can only think of 1 other paper-- Clark et al on Canadian bread)-- that does this.👏
Deep in my JMP, I define an operator cop(G,Y) that transforms joint dist. G(X) so its marginal in Y \subseteq X is U[0,1] .
So cop(G(X),X) is the copula of G.
I've personally called this operator the "copulator" for years. And I just realized.
🚨NEW PAPER fresh from SEAs! I provide a framework to more rigorously think about the distributional impacts of firm conduct (e.g. markups) on consumers. Key idea: separate the *causal* effect of a consumer’s wealth on demand from the *correlation* of wealth and tastes. 🧵
To sum up, journal policies against scraped data are regressive, as they’ll mostly affect researchers w/ fewer resources, and not great for research as a whole. I really hope new AEA policy allows for scraped data, even w/o explicit website owner permission.
Last week, we had the 16th annual FTC Microeconomics Conference. This year’s conference was amazingly well attended—no surprise given its reputation and the quality slate of papers. Here are some (extremely condensed, Tweet-sized) summaries!
Focusing only on the economics of price controls...
call me crazy, but aren't there reasonable models (and perhaps reasonable parameter values) where price caps (or floating price caps) are sensible?
Here's Ignacio Cuesta's JMP, for instance
To grad students teaching for the first time this month:
I once introduced myself to students as "You can call me Matt, though my coworkers insisted on calling me Feisty Leisty." Never brought it up again.
In my course evals, several students referred to me as Feisty Leisty.
Finally hitting the "whatever, the paper is what it is, I'll make no changes and send it somewhere else immediately" threshold of journal rejection counts 🤷♂️
Just here to say
@IIOC_IO
was absolutely fantastic and seeing so many cool papers (from early phase projects to polished JMPs) and getting to present my new inequality paper in front of a diverse (by IO standards) and enthusiastic group was pretty darn invigorating.
Friends: don't read any of these publications. Read AER, JPE, Econometrica, and ReStud. JEP or JEL if you want beach reading. Maybe QJE but their whole review process seems a bit weird.
If you want to learn about the causes of inflation, I’d stop reading the Times. Read instead
@TheProspect
’s pricing feature. Or the
@LeverNews
. Just anything but the Times. Please. What an embarrassing piece of advocacy disguised as journalism.
Probably my favorite part of working at the
@FTC
(other than my research time) has been serving as a co-coordinator for our *outstanding* seminar series.
We've had some awesome visitors! A summary🧵of the seminars I hosted (full list at ):
Excited for
@IIOC_IO
in Boston this weekend! I'll be presenting new work on "Dynamic Regulation with Firm Linkages" (joint w/ Nicholas Vreugdenhil, who is not on Twitter) and avoiding Dunkin' at all costs.
With all these takes on the Chicago tradition, I would like to plug the cross-town Northwestern tradition of eliminating assumptions one-at-a-time until Pr( X |data) \in [.03,.98] and these bounds are sharp.
From one conference to another! Presenting "Algorithmic Pricing, with Humans" in front of other DC-area IO economists tomorrow. Excited to hear feedback about managers working alongside algorithms to set prices, and to show off my nifty animated Beamer slides😎
Between
@VictoriaMarone_
and me you could always tell who's been hard at work based on the ratio of CARA utility functions to convolutions our office whiteboard.
Congrats on getting this ~tour de force~ of a paper published!
Research by Victoria Marone ("When Should There Be Vertical Choice in Health Insurance Markets?") is featured in the new issue of the American Economic Review.
@VictoriaMarone_
How economics has changed through the decades since the 1950s, as seen in the paper titles of the economics journals AER, JPE and QJE.
Paper by
@hugomoises
and Brice:
Ht
@DurRobert
I'm not presenting at
@IIOC_IO
this year ☹️
but I will be attending, so come find me 🙂
between breaks writing my next paper (which I'm very excited about) 😎
I finally just submitted this guy, and my Twitter game has honestly improved since I first posted about it, so an updated 🧵 on my (mostly applied theory) paper: “Algorithmic Competition, with Humans.”
Good thread, and consistent with my favorite slide deck in all of economics (from
@PhilHaile
). Even "reduced form" estimating equations are (derived from) some theory! Anyway:
Many students ask me why I work with structural methods, that is theoretical models mapped directly to data, parametrically or nonparametrically. [1/n]
Prof Nevo taught me 2nd year. I once chatted w/ him on my way to the CTA about "Bayesian Persuasion." I was nervous and rambled; he was patient.
After walking a while, he asked where I was going. I realized I wasn't going anywhere in particular and darted away without a word.
Theory's more subtle. There are two kinds of IO economist.
Type I reading theory: 🤯
Type II reading theory written since the Tirole textbook: 🥱.
But if it's pre-Tirole textbook (and especially if it's in the Tirole textbook), it's 🫡
Been grappling with this amazing paper by
@skominers
et al.: how to design a market when preferences reveal something (but not all) about wealth/social/Pareto weights. But I still have no intuition for why 4 (or fewer) prices w/ rationing is all you need
Should Amzn be allowed to self-preference results? Must estimate *structural model of consideration set formation* to examine counterfacual search policies.
Tai finds tying Amzn's hands is bad. Better to "split" the site into private label store and third party store. Good JMP.
Department of Economics PhD Candidate Tai Lam’s research interest is Industrial Organization, Applied Microeconomics. Learn more about H. Tai Lam at & other Northwestern Economics Job Market Candidates at
IO twitter alit w/ people trying to interpret permutations of
areg [d.] [concentration, prices, markups] [l3., d3.] [concentration, prices], absorb([industry])
and I'm longing for those fleeting, shining days when econtwitter was fruit twitter. So, here are my hot fruit takes:
👇Great example of why IO scholarship is often one small market at a time, and antitrust law is often rule-of-reason.
These approaches have vocal opponents, but ultimately, there are few generalizable rules because markets vary in tastes, technology, institutions, etc.
So why isn't MPD always pro-competitive?
Section 7 contrasts our findings to the literature (
@FernandoLuco
@dprbyrne
@AterItai
@simonmartinecon
@haucap
and many others off Twitter)
Key for success:
👉 Producers well-informed before
👉 Info easily accessible
👉 Strong uptake
Kind of loving this debate. If there isn't a panel at the next Northwestern Antitrust Conference on "market power, aggregate shocks, and pass through" I'm teaching myself Dynare and switching to macro.
My job market paper has been rejected from six different journals, and I have been rejected from Yale six different ways. So I would probably say the time I didn't make the varsity golf team.
Another pundit take on greedflation. This one is fairly nuanced.
Anyway, IO econs do have actually things to say here. Ryan Westphal's JMP is a great example: consumer beliefs about (cost) inflation affect search and pass-through.
Interesting takeaway from
@MattBruenig
here: Most of the studies folks on the left are citing to prove that corp. greed caused inflation are actually telling a straightforward mainstream econ story about how inflation expectations are pushing up prices.
Economics offers problem-solving tools, and Duke’s 8 new Econ faculty members show just how many problems it can help solve.
Help us welcome them and get to know their research.
.
@nelson_bvsa
After 3 years, we have finally submitted "Dynamic Regulation with Firm Linkages"! Already posted a summary thread before, but the gist: linking scrutiny past pollution offenders with scrutiny of their co-owned plants is *quite* efficient!
I know it's hard to get data for one market let alone many, and I know we aren't macroeconomists, and I know cross industry studies are historically problematic, but **MORE OF THIS PLEASE**
There's a lot of debate about whether antitrust has been too lax. It's a difficult question! You need to quantify the effects of a representative set of mergers and predict outcomes with more stringency.
@bhattacv
, David Stillerman and I do so in:
🧵
On Tuesday the
@FTC
issued a final rule that effectively bans noncompete clauses in US labor contracts. Given the wide-reaching impact, there has been (understandably) a lot of debate, and also some confusion. Two issues are particularly contentious.
The first is the economic
@mdoepke
spent his last first-year macro lecture telling us how to PhD. Years later, the two that stuck with me seem right (even if I didn't always abide):
1. Don't read too many papers. Waste of time. Go to talks instead
2. Write papers, even if they're bad ones. It's practice.
Excellent advice (and so hard to follow 🫣)! What other advice/rules of thumb are there for (new) PhD students? I'd love to compile everyone's ideas.
(Asking for someone who did her PhD with little to no guidance and who's about to supervise her first PhD student soon.)
Short 🧵: Cereals and concrete are *OUT*. The hot new lab for writing awesome papers about key IO topics is: French telecom!
Two of favorite papers I've read/seen in the last ~18 months:
5. ASSAs: Get to see old friends
4. FTC Micro: I'm biased
3. SEAs: Casual and democratic
2. NW Antitrust: Intimate, curated, Chicago in September
1. IIOC: Pretty much my Christmas