Eat 20 Potatoes a Day…. For Science

Several people have tried eating an all-potato diet for a few weeks and reported losing lots of weight with little hunger or effort. Could this be the best diet out there? Or are we only hearing from the rare success stories, while all the people who tried it and failed stay quiet?

Right now we don’t really know, but the people behind the Slime Mold Time Mold blog are trying to find out:

Tl;dr, we’re looking for people to volunteer to eat nothing but potatoes (and a small amount of oil & seasoning) for at least four weeks, and to share their data so we can do an analysis. You can sign up below.

I was surprised to see that they are the ones running this, since they are best known for the “Chemical Hunger” series arguing that the obesity epidemic is largely driven by environmental contaminants like Lithium. The conclusion of that series noted:

Bestselling nutrition books usually have this part where they tell you what you should do differently to lose weight and stay lean. Many of you are probably looking forward to us making a recommendation like this. We hate to buck the trend, but we don’t think there’s much you can do to keep from becoming obese, and not much you can do to drop pounds if you’re already overweight. 

We gotta emphasize just how pervasive the obesity epidemic really is. Some people do lose lots of weight on occasion, it’s true, but in pretty much every group of people everywhere in the world, obesity rates just go up, up, up. We’ll return to our favorite quote from The Lancet

“Unlike other major causes of preventable death and disability, such as tobacco use, injuries, and infectious diseases, there are no exemplar populations in which the obesity epidemic has been reversed by public health measures.”

That said, they did still offer some advice based on the contaminant theory that is consistent with the potato diet:

1. — The first thing you should consider is eating more whole foods and/or avoiding highly processed foods. This is pretty standard health advice — we think it’s relevant because it seems pretty clear that food products tend to pick up more contaminants with every step of transportation, packaging, and processing, so eating local, unpackaged, and unprocessed foods should reduce your exposure to most contaminants. 

2. — The second thing you can do is try to eat fewer animal products. Vegetarians and vegans do seem to be slightly leaner than average, but the real reason we recommend this is that we expect many contaminants will bioaccumulate, and so it’s likely that whatever the contaminant, animal products will generally contain more than plants will. So this may not help, but it’s a good bet. 

Overall though I think the idea here is to ignore grand theories and take an empirical approach. The potato diet works surprisingly well anecdotally, so lets just see if it can work on a larger scale. Seems worth a try; I’m sure plenty of my ancestors in Ireland and Northern Maine did 4-week mostly-potato diets and lived to tell about it. You can read more and/or sign up here. Let us know how it goes if you actually try it!

What if You Didn’t Have to File a Tax Return?

Now that we’ve all made it through the 2021 tax filing season, it’s worth thinking about a recurring question in tax policy: is it possible that most of us wouldn’t need to go through this annual ritual? Couldn’t the government just tell us how much we owe (or are due as a refund), or better yet, just deduct the correct amount from our paycheck so we’d have paid the right amount?

We need to imagine such a system: it exists in many developed nations around the world! And it’s true that, at least for many taxpayers, the IRS already has all the information on you it needs to calculate your taxes.

But how many US taxpayers would this be beneficial for? A new working paper which tries to quantify this question. In “Automatic Tax Filing: Simulating a Pre-Populated Form 1040,” the authors use a large sample of tax returns to estimate how many taxpayers a pre-filled return would work for. The results are almost split down the middle: it would work well for maybe half of US taxpayers (41-48% of taxpayers, depending on how we are defining successful). For the other half, it wouldn’t give you an accurate estimate of how much tax you owed.

And the errors can be large. For example, the authors report that “two-thirds of the cases where the lower bound approach is inaccurate, the pre-populated liability is higher than the reported liability, with a median gap of $4,200.” Note: looking at the tables, I think they mean to say “mean,” not “median” here, with the median being $1,400. Still, that’s a lot of errors in a direction that would hurt taxpayers if they didn’t fill it out on their own or pay someone to do it. And it’s not just one thing that’s causing pre-filled returns to be wrong. You might think itemized deductions are a big issue, and they are, but only for about 11% of returns (and in only 4% of returns is this the only issue). They find that 9% of returns didn’t even have the reported wages matching what the IRS showed!

Does this mean that pre-filled returns are doomed in the US? Perhaps not! They seem to work much better for younger, single filers, and as well as filers with very low income, as Figure 1 from the paper shows. Even so, the 60-80% success rate (depending on criteria) for very low income taxpayers isn’t especially encouraging. But one upshot of a pre-filled return is that there are possibly millions of taxpayers (maybe 8 or 12 million?) that don’t file a return because they aren’t legally required to (too low income), but they would benefit if they did because of refundable credits like the EITC and Child Tax Credit.

Maybe there is a compromise position. The IRS could send you a “suggested tax return,” but allow you to modify it. I suspect that, in most cases, those who are currently paying for a person or software to do their taxes would still do it. You can’t know if you are in the one-half of taxpayers where this information is accurate! The IRS could provide a list of “common reasons why you may be in the half of pre-filled tax returns that are wrong,” but we’re still shifting the burden back to the taxpayer.

I would like to suggest, instead, that there are a few changes we could make to our tax system (“simplifications,” if you will) that might make pre-filled returns much more viable.

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How to Read Aloud Kindle and Other Text on iPhone, iPad, and Android

What if you could get your phone or tablet to read Kindle or other text aloud to you? I have recently come across an easy way to do this. This is an economics blog, so I will note that this approach saves considerable money versus paying for audio books like Audible, or paying for the Narration option on Kindle.  Most of us already have text books we have bought from e.g. Kindle. Also, if you search on the subject, there are various sources for free on-line books, including hundreds of thousands titles available through Libby/Overdrive via your public library. This text-to-voice method should work with all of these e-books.

Directions for iPhone/iPad: A short YouTube video “How to get your iPhone to read Kindle books aloud” by Kyle Oliver tells you all you need to know. The key step is to go to Settings, then Accessibility, then Spoken Content. At that screen, turn on Speak Screen. With Speak Screen ON, whenever you are on a page with text (including Kindle or other e-book), you swipe down from the top of the screen with two fingers. That will activate reading of that page of text. Also, a little speech control panel will appear. That panel will allow you to play/pause/jump forward and back. It will also allow you to  you toggle between multiple speeds: 1x, 1.5x, 2x, & 1/2x. 

If you want, while you are in the Spoken Content screen you can also turn on Speak Selection. That will give a Speech option to read aloud just whatever text that you have select, and then stop.

Also, on in the Spoken Content screen there is a Voices link, for selecting what voice you want to hear. You can experiment with various voices. I have found that the male Siri voice (“Siri voice 1”) is preferable. The female Siri is too syrupy sweet listen to for long, and most of the other voices are robotic. I find that if I select a new voice, I have to turn the reading off, then on again to get the new voice to start working. One more tip from that YouTube is to dim your screen, since with continuous reading of Kindle pages, the screen will stay on, and drain the battery quickly if the screen is bright.

Once you do the two-finger swipe down to commence reading, it should keep reading onto following pages as well. For unknown reasons that does not work sometimes. I find that using the jump forward then jump back buttons on the little speech control panel unsticks this functionality.

For Android: The YouTube Kindle Android Text to Speech by Ad Vice has similar directions for Android. In this case you end up opening the speech function by triple clicking the home button.

There is a harder way to do all the above, which is to download a separate text-to-speech app like Speechify or Voice Dream Reader. These apps will read most text that is on your screen, but NOT Kindle or other e-books that have Digital Rights Management (DRM) protection. For these e-books, you’d have to download yet another app such as Epupor Ultimate on your computer, download your Kindle files onto your computer, then run Epupor on these files to create unprotected versions. Then, I suppose, load these files back onto your phone/tablet where the text-to-speech app can access them to read aloud. This does not seem worth it (compared to the simple method above using built-in iPhone/Android capabilities) unless you want to utilize some extra feature of the outside text-to-speech app.

Note: under the subject of low cost text to speech, there are apps like Librivox or (using your local library) Overdrive or Libby that offer free audiobooks – see this article by LifeWire. If a book is already available as an audiobook, it is probably better to use that format for listening to it, rather than downloading it in text form and then using the approach here for listening.

Let’s Talk about the NBER

The National Bureau of Economic Research (NBER) sent out its membership invitations this week. My twitter timeline quickly filled with explicit congratulations and oblique commentary. My private messages filled with…less than oblique commentary. Academia has always been hierarchical and economics has never been an exception. Talk of “top” departments and people is ubiquitous, but those categorizations remain fuzzy – “There are 40 departments in the Top 25” is a common adage. Aside from the obvious humor, I think there is also some healthy truth to it. There are lots of good departments and no one has any final say on who they are. Departments compete for recognition of contributions and the rewards that come from status in the profession. Having 40 or 50 “top 25” departments just means more status for everyone, which strikes me as nothing but welfare enhancing.

The NBER, on the other hand, has hard boundaries of membership. Though I doubt it was founded with any such intention, it has become the club within the broader profession that comes with more prestige than any other. Exclusionary clubs are not unto themselves problematic, but it is hard to shake the feeling that the advantages exclusive to NBER members are greater than ever.

For those who are sick of preamble, let’s start building a hypothesis. Academic economics has acquired some pathologies of publication and promotion that are creating an increasingly grumpy and anxious profession, particularly amongst our junior colleagues. These pathologies are manifest as broad public goods (e.g. timely evaluation and dissemination of research to inform tenure and promotion decisions, professional network development, the transition into a discipline more dependent on significant outside funding, etc.) that the discipline is consistently failing to produce.

The NBER is producing exactly these public goods. They didn’t create any of these problems, but for their members they may have solved them.


Originally founded as a research institute in 1920, largely to produce and disseminate macroeconomic data, the NBER has evolved into a collection of 20 research programs and 14 working groups, all built around a bureaucratic hub that has 100 years of institutional experience running research groups, disseminating research, and organizing events. It has a storied history and deserves every ounce of the prestige it both enjoys and bestows.

From the point of view of any scholar looking to get a research agenda off the ground, an affiliation with the NBER offers 4 key advantages or “club goods”:

  1. The prestige of listing an NBER affiliation at the top of your CV and on every paper you write and submit.
  2. Invitation to NBER conferences, most importantly the Summer Institute collection of meetings every July in Cambridge, MA.
  3. The option to channel your grants through the NBER instead of your home institution’s bureaucracy.
  4. Permission to disseminate your new papers through the NBER working paper series.

I would like to contend that all 4 of these privileges confer enormous advantages for any scholar, doubly so for young faculty. I am not contending that these advantages are unearned or even necessarily unfair, but I do think that they are often underappreciated in their magnitudes, and that this under-appreciation offers some insight into the frustration expressed by those on the outside. So let’s talk about them.

Signal value #1 may be the most or least important, depending on your point of view, but it’s definitely the least interesting. Every CV is filled with myriad signals, the NBER is just another one. In fact, the only aspect worth discussing is its seeming correlation with another key signal: PhD-granting institution. It seems, with nothing more than a glancing ocular regression, that being invited to join as a faculty research fellow (i.e. a pre-tenure affiliation) correlates heavily with having a Cambridge, MA PhD or having an PhD advisor at an elite institution who is themselves an NBER Research Associate (i.e. post-tenure member). There’s nothing inherently bad here, but this compounding of highly correlated signals is a little ominous for the outsider trying to get their own career off the ground. If exclusion from the club is unto itself what bothers you the most about the NBER, you’re missing the point and you should probably just get over it. And yourself, for that matter.

Conferences. #2 is more interesting because the NBER conferences, including the Summer Institute, are widely appreciated for the important networking events that they are. What I don’t think is as appreciated are how they relate to the journal reviewing process. First, if you hang out there long enough people will learn your name and face. While academic economics is famously rigorous and occasionally brutal in its seminar and reviewing culture, the fact remains that humans are more forgiving, more generous of the benefit of the doubt, once we put a face to a name. It’s just harder to be mean or assume the worst in someone once you’ve had a real conversation with them and confirmed their genuine humanity. Second, and this is probably more important, to present a paper at an NBER conference is to present to the pool your eventual reviewers will be drawn from and receive pre-submission referee reports. Being able to learn the perceived weaknesses of your paper before submitting to the magical top-5 and elite field journals is a prodigious advantage, particularly for scholars who don’t yet have a decade of experience trying to publish in their field.

Grant Management. Being able to funnel grants (#3) is probably both the most boring and most underappreciated of member advantages, particularly for scholars building research agendas at smaller schools that place more teaching and service demands on faculty. Being awarded a significant grant can be something of a curse to the pre-tenure scholar if their institution doesn’t have the internal human resources and institutional experience to manage a grant properly. Losing 15 hours a weeks to bureaucratic transaction costs is crippling. If I were trying to start a career running field experiments, I’d probably spend my first semester camped out on the NBER’s front porch like I was petitioning for admission to a Buddhist monastery.

Working Papers. Access to the working paper series (#4) is probably what would strike non-professors, or even just non-economics professors, as trivial, but is actually the most important. I know it’s what I want access too. Lets explain why:

Academic economics has a publishing problem. This is nothing new. What I think is underappreciated is that the NBER solved it for its members.

When the authors of a paper feel that its contribution has been established, that it can exist independent of any supplemental explication with tolerable risk of significant changes between now and its final form, they put it out into the world as a working paper. As the submission and review process has lengthened over the past few decades, the working paper stage of a project’s life cycle has grown in importance. It’s not crazy to suggest that most economics papers reach their total citations “half-life” while they are still working papers.

Whether that sounds crazy to your or not, however, doesn’t actually matter. What matters is that the timeline from first submission to acceptance at a journal continues to expand while the tenure clock remains fixed at 6 years. I’ve written before about how we might mitigate some of the problems in the journal publication process, but that’s a far less pressing concern if you are an NBER member because your papers enter the field as contributions through their NBER-branded working paper series years before acceptance at a journal. The prominence of NBER working papers is sufficient to the point that publication for members exists solely to provide additive signals of quality for long-term career tracks. The contribution itself, how it is internalized in the field and propogated forward within the authors’ research agendas, is adjudicated by the jury of the authors’ peers years before an editor acquiesces and agrees to sacrifice invaluable journal real estate as tribute unto the paper’s now long established contribution. Published papers are old news.

It is no less important that research also enters the seminar, media, and policy cycle as soon as it is disseminated as an NBER working paper. I’ve been in discussions where whom to invite to a workshop reduced for many to nothing more than scrolling through the previous 3 months of NBER working papers. Journalists subscribe to the series for ideas on columns and features. Thinktanks similarly fill their calendars of lunch talks and policy events. The authors will know if their project is a success, or if they are on the wrong track, months before their first rejection and years before their final acceptance. The world learns of them, their research, and their specific expertise through a channel entirely separate of formal peer review or historic outlet prestige.

The NBER solved the economics journal problem by disintermediating scientific debut and evalutation from the publication process. But again, only for their members.

Have I said enough about the working paper series? Let me summarize with a only a touch of hyperbole: if I ran a regression to find the determinants of expected citations, I would expect nothing on the right hand side of the equation, not university affiliation, not PhD-granting institution, not even journal ranking, would have a bigger coefficient than a binary indicator for was it an NBER working paper.

So what should we do?


First of all, I’m not a member, so there is no we about it. Second, I’m not sure we should do anything. It’s not my club, it’s been wildly successful, and just because some of us don’t get to enjoy it’s benefits doesn’t mean it should be changed. So, rather than complaining about the NBER or telling them what to do, I would like to suggest that the discipline has some public goods problems. and that the NBER might be able to contribute to mitigiating them.

One more thing to keep in mind – the club goods provided by the NBER are broadly characterized by decreasing returns to scale. Personal time and attention simply do not scale, which means the answers to most concerns will rarely lie in increasing broad membership or access (though I agree fully that the solution is without question inclusive of letting you in, as you are very smart and grossly underappreciated).

That all said, let’s now revisit the four NBER club goods currently exclusive to members.

#1. The prestigate of membership. I hope you didn’t read this far hoping I’d try to “solve status” in academia. That said, when an exclusive club acquires this much value, you have to expect that the process of admission is going receive all the more scrutiny. As a grossly uninformed outsider, the shadows I see on the wall of a cave from a considerable distance through a crack in the wall is an irregular nomination process that probably bottlenecks in some places while spreading idiosyncratically across networks in others. My guess is that a lot of people who are asked to provide 100 hours of attention in an already 70 hour work-week are effectively being tasked with filling in the next round of nominations. This leaves them with little choice but to take the path of least cost, and that path is making nominations of the former students they came across in their own hallways and those of their closest peers. Occasionally this also grants opportunties for gratuitous favortism and subsequent resentment. More importantly, though, in increases the tightness and redundancy of academic networks, furthering the gap between insiders and outsiders.

How do we fix this? We probably don’t, but here’s one thought: delay the nomination process. If this is the most prestigious club in economics, why are we nominating new PhD recipients before they’ve produced a research agenda? One way to make an institution’s admission process seem more transparent is to have criteria that are at least partially realized, rather than just subjective potential. It probably wouldn’t hurt to make nominators into publicly observable sponsors of record. Never underestimate shame as a tool for mitigating the various ills than can characterize an institution. (NB: these could actually be internally transparent. Remember: just because I am writing this doesn’t mean I am particuarly well informed)

#2. Conferences. An insider has sugggested to me that the Summer Institute used to be far easier to crash, but relented in the face of skyrocketing costs, flooded sessions, and problematic favoritism of local schools. Reiumbursing travel costs extended the radius of access, but also dramatically increased the cost per attendee to the NBER.

One suggestion: the NBER should only pay for the expenses of graduate students and junior faculty. Everyone else, including members, should pay their own way (or at least expense the trip to their home deparments). The hope is that this will make it easier for the NBER to subsidize access to non-members outside of the immediate ring of members. It may also be beneficial to prioritize non-members who have never previously attended. I’ll give you one more, and this works even better if membership nominations are delayed until later in careers: reserve presentation slots in the winter meetings exclusively for junior scholars and non-members.

#3 Grant organization I got nothing except maybe allow non-members to apply for grant-organization access. I mean, if there’s a scholar from a smaller school who’s already established a track record of outside funding in desperate need of institutional support for their research, this sure seems like a hell of a public good that the NBER could provide. Would a lot of people take advantage of it? I have no idea. But it certainly sounds promising and my guess is that it would actually net add to the NBER coffers.

#4 The working paper series. I’ve thought about it a lot, and this is what I’ve got: allow non-members to apply for “working paper series (NBER WPS) membership.” There’s simply no way around the fact the NBER itself cannot possibly scale to include every scholar who “deserves to be a member”. That said, I can’t help but think decreasing returns to scale are going ramp up a lot later for the working peper series.

The changes I imagine are relatively straight-forward. Scholars are allowed to apply for NBER WPS membership, submitting a CV and a recent working paper. If they are denied they cannot apply again for 3 years. If they are admitted they may submit papers to the WPS, on the understanding that the NBER reserves the right to apply a more rigorous review process than with full members and to deny any paper at their discretion. This isn’t a trivial cost proposition, mind you, and it would be entirely borne by the NBER, but they have access to sufficient human resources (cough graduate students) to provide cursory reviews of papers to make sure they are up to basic snuff, pushing potential questions up the chain when a paper might not be of a high enough standard. This would be an enormous service to the profession that they are in a unique position to provide.

In a final closing sentiment, let me state a few things that are probably obvious, but hell, you read this far. I have the luxury of being a tenured professor, so the consequences of these institutions are pretty minimal to me. But I’ve also been a bit of an outsider in the profession since the beginning. I was 9 years and two “top-5″s into my career before I got my first seminar invite, 10 years before I attended my first NBER summer institute. Which is to say I am sensitive to the frustrations of younger scholars who feel like there are walls between them and what they need to get their careers off the ground. We shouldn’t dismiss their genuine (and not unreasonable) anxiety as prestige envy or a grotesquely privleged version of populism. The discipline of academic economics has real problems, and if the NBER has figured out internal solutions to some of those problems, then I’d like to think they might be interested in spreading access just a little farther.

Content moderation strategy

Anyone can comment on this blog. We’d love to see more comments. Challenging our ideas is fine. Telling us that you like our work is encouraging.

If you are in the know, then you assume we have a comment moderation policy, because everyone needs one. If you have never run a website then you might think it is possible to simply have an open form that anyone could type into and get immediately published on the platform.

Comments come in every day, but most of them never get posted. We are not against free speech or silencing an opposition. Most of the comments, if you can even call them comments, are spam. Sometimes spammers try to get posted by saying that they love the site, and sometimes the text seems like AI-generated pornography. The words are not written by humans or at least not humans who have actually read our content.

I don’t think it’s smart to be 100% transparent about our “algorithm” for filtering out this spam. That would make it easier to for bad actors to accomplish what they want to accomplish.

To our human readers, please comment. Your comment will get posted, although sometimes it might take a minute or even hours to get through. We are not censoring ideas, yet we need a moderation policy or else this place would not be fun. People would not want to wade through spam.

Elon Musk buying Twitter is the big news this week. He wants to enhance free speech on the site and, according to him, make it more open and fun. Some fans are hoping that he will make the content moderation and ban policy more transparent. Maybe that’s possible. Maybe he can improve the site.

My point is that if you have not been on the admin side of an internet forum then you might not realize the challenge it presents. There are trade offs involved. I believe that there can be improvements to the current system at Twitter. However, if you want to be taken seriously be tech folk then ask for a system that is possible. A substantially better experience might be incompatible with the site being free to users.

In our case, we could improve our system at EWED. Real people who comment will not like the lag, and fixing that is a technical problem. More time and money could solve it, but this site makes no money.

The economics insight is that you get what you pay for. Studio executives make the movies they believe you will pay for. We get the politicians we bother to vote for. Journalists report what they get paid to write.

Twitter could create a paid user tier. Paid users would be entitled to speak to a human on staff at Twitter in the event that they get censored and have the option of an appeals process.

I am used to getting a lot of services for free online. New companies roll out a huge free initial offering to harvest users and data. I have spent most of my adult life in that roll out phase. Eventually the party stops and investors want to see a revenue stream. Maybe I should start paying for the internet services I value. Maybe part of the reason the conversation is so rancorous is that we are transitioning away from everything being free. Inventing social media is sort of like humans discovering fire and cocaine at the same time! We are still figuring out how to use these tools effectively and safely.

I think a bad scenario happens if we cannot transition over to a patronage model. Remaining trapped in a free stuff mentality would be worse in the long run. I hope Napster didn’t ruin me. In an ideal world, I would be willing to pay for social media and also never spend more than 2 hours a day scrolling on any open platform. We should try for that. We should supplement our online reading with content that has made it past a publisher. For now, one way to get around Twitter censorship is to buy and read books.

AS-AD: From Levels to Percent

The aggregate supply & aggregate demand model (AS-AD) is nice because it’s flexible and clear. Often professors will teach it in levels. That is, they teach it with the level of output on one axis, and the price level on the other axis. This presentation is convenient for the equation of exchange, which can be arranged to reflect that aggregate demand (AD) is a hyperbola in (Y, P) space. Graphed below is the AD curve in 2019Q4 and in 2020Q2 using real GDP, NGDP, and the GDP price deflator.

The textbook that I use for Principles of Macroeconomics, instead places inflation (π) on the vertical axis while keeping the level of output on the horizontal axis. The authors motivate the downward slope by asserting that there is a policy reaction function for the Federal Reserve. When people observe high rates of inflation, state the authors, they know that the Fed will increase interest rates and reduce output. Personally, I find this reasoning to be inadequate because it makes a fundamental feature of the AS-AD model – downward sloping demand – contingent on policy context.

At the same time, I do think that it can be useful to put inflation on the vertical axis. Afterall, individuals are forward looking. We expect positive inflation because that’s what has happened previously, and we tend to be correct. So, I tell my students that “for our purposes”, placing inflation on the vertical axis is fine. I tell them that, when they take intermediate macro, they’ll want to express both axes as rates of change. I usually say this, and then go about my business of teaching principles.

But, what does it look like when we do graph in percent-change space?

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Inflation and GDP Growth Around the World

Kalshi cofounder Tarek Mansour recently shared this graph:

In hindsight it seems like an obvious graph to make, and a good way to teach Aggregate Supply / Aggregate Demand models, but I don’t actually recall seeing much like this. One obvious improvement is to include more countries. I do so below using data from Trading Economics, showing all 182 countries that have recent data on both annual GDP growth and inflation. I also flip the axes to be more consistent with the convention in economics:

This makes clear both the costs and benefits of including all countries. We see just how extreme some outliers are: hyperinflation in Venezuela, Sudan, Lebanon, and Syria; a severe contraction in Libya; and huge growth in Azerbaijan and the Maldives (errors in the data?). But all the more typical countries blend together. So here I zoom in on the more typical countries:

This makes clear the strong aversion to deflation that most countries have. Well over a hundred countries here, many with very low inflation, but only in South Sudan does inflation actually go negative. Real GDP growth does not exhibit the same sharp divide at zero, presumably because its much harder to central banks to fine-tune. Now I try to zoom and enhance one more time:

But things are starting to just get messy, so its time to drop more countries. Here I focus on the 30 largest economies (minus Turkey, which breaks the scale on inflation):

Here we see:

  • Japan is demonstrating stagnation/ low aggregate demand / “running cold”
  • Brazil, Stagflation (negative supply shocks?)
  • Poland, high aggregate demand / running hot
  • Saudi Arabia and Israel, high growth without high inflation (positive supply shocks?)

The US is on the higher end of inflation, and I still think we should be doing more about this, but in this graph we don’t look like a huge outlier. We’re all still working through Covid-related shocks. But the very latest quarterly data today (not reflected in these graphs) showed negative GDP growth in the US, sending us toward the “Stagflation” quadrant and making the Fed’s job much harder.

Are the COVID Vaccines Effective at Preventing Death?

A recent analysis by the Kaiser Family Foundation of CDC data suggests that about 234,000 COVID deaths in the US could have been prevented if everyone was vaccinated. That’s about 25% of all COVID deaths throughout the pandemic, and about 60% of COVID deaths since June 2021 (roughly the time when most older adults in most states had had a chance to be vaccinated).

The first way to think of that death rate is tragic, given that so many lives could have been saved. Rather than being the high-income nation with the highest COVID death rate, the US could have been more in line with countries like Italy, the UK, and France. The US actually had a lower COVID death rate than Italy and the UK when the vaccine roll-out began, and today we could be at about France’s level with better vaccination rates.

But there’s a flipside to the KFF numbers. If 60% of COVID deaths since June 2021 were preventable, that means 40% weren’t preventable. Furthermore, the same data show that about 40% of COVID deaths in January and February 2022 were fully vaccinated or had boosters. That sounds like the vaccines might not work very well! So what does this all mean? Let’s dig into the data from the CDC a little bit.

The first, and most important thing, to recognize is that most American adults are vaccinated (about 78%), so unless vaccines are 100% effective (and they aren’t, despite some public officials overenthusiastic pronouncements early in the vaccine rollout), there are still going to be a lot of COVID deaths among the vaccinated. If 100% of the population was vaccinated, 100% of the deaths would be among the vaccinated. The key question is whether vaccines lower the chance of death.

And they do. Let’s see why.

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New Fossil Discoveries Shed Light on When and How the Dinosaurs Died Out

For nearly 200 million years, reptiles were the dominant animals on land, in the air (e.g. pterodactyls), and in the sea (e.g. mosasaurs). They were efficient herbivores, munching on lush vegetation, and also were efficient carnivores (think: T. rex). They were protected by scaly skin and often horns or armor plates. Mammals at this point were typically small, rat-like creatures, hiding in their burrows from the reptiles, and creeping out at night to feed.

However, the Age of Reptiles came to a sudden end 66 million years ago. Dinosaurs and many other large reptiles disappeared, which gave opportunity for mammals to rapidly evolve and proliferate to fill many key ecological niches. What happened to all those reptiles? The leading hypothesis is that a huge meteorite impacted the earth near what is now the Yucatan peninsula of Mexico. The dust and aerosol cloud that was thrown into the atmosphere darkened the skies around the world enough to shut down photosynthesis long enough to starve the reptilian herbivores, which in turn starved the reptilian carnivores. Somehow enough mammals survived the event to repopulate the earth (my guess is they ate insects which ate dead dinosaurs).

The impact blasted tons of molten rock droplets high in the air, which then fell as little glassy spheres or dust particles all over the world, and especially in North America. Where these “tektites” fell in undisturbed places like bogs, they accumulated as a distinct layer. Over time, these spheres decomposed into a clay layer which is distinguished by a high iridium content. Here is a cut-out section of rock which shows this meteorite-derived boundary layer between lower (older) rocks that contain dinosaurs and an overlying layer where dinosaurs are absent:

Rock section showing layers from the Cretaceous Period (when dinosaurs lived), overlaid by boundary layer material from the asteroid strike 66 million years ago, and then younger Paleogene rocks (no dinosaurs). Source: Phil Manning/Uni of Manchester, UK.

Exactly When and How Did the Dinosaurs Perish?

The picture is complicated by the fact that very few dinosaur fossils have been found in roughly three meters (ten feet) of sedimentary rocks immediately below the Ir-rich meteorite layer. This is known as the “three-meter problem”, and suggests that the dinosaurs had already largely died out from other causes; maybe the meteorite impact just finished them off. Shortly before the impact event, there was a massive series of volcanic eruptions in the Deccan Traps area of India which released enormous amounts of sulfur dioxide and other gasses in the atmosphere, which probably altered the climate. It has been proposed that this fatally stressed the dinosaur populations.

Recent finds from the “Tanis” fossil site in North Dakota have brought clarity to this question. Apparently when the meteorite hit in what is now Mexico, it created a forceful earthquake. When this tremor rolled up to North Dakota, it caused several large waves of water to surge upstream in a creek near the sea, which deposited layers of muddy clay on preexisting sandbars. This occurred several hours after the impact. Providentially, that was just when some of the small glassy spheres which were blasted into the atmosphere were raining down on North Dakota. Some of these spheres, and even their little impact depressions from smacking into the mud at terminal velocity, have been found in the layers of sediment deposited on the sandbars. So we know that whatever fossil remains we find in these sediments were entombed there on the very day the meteorite hit.

It turns out that numerous fossils of dinosaurs have been found in these Tanis mud layers, indicating that there was a thriving community of huge reptiles right up until the impact. These finds include a dinosaur hip/leg with exquisite details of skin preserved, and an egg with a partly-developed pterosaur embryo visible in it:

Ornithischian dinosaur hip/leg/skin from Tanis site.  Source: BBC

Fossilized egg with bones of pterosaur embryo in it. Source: Yahoo

Also, immediately below the mud deposit layer have been found numerous dinosaur footprints, indicating the juvenile and adult dinosaurs from a variety of species were tramping around shortly before the impact event:

Source: Riley Wehr et al. paper at 2021 GSA Conference

Bottom line: it looks like we humans do owe our existence in large part to this one, seemingly random meteorite impact which cleaned out the dominant reptiles and made room for mammals.

Attention as Rational Addiction

I’ve never gotten this much attention before. Which is to say, my writing receives a small sliver of attention on occasion, but that small sliver is nonetheless far more than I’ve received previously in my life. To put it in better context, I’ve had a couple posts and tweets go mini-viral, which by the standards of major pundits or celebrities amount to little more than a throwaway post, but by the standards of my life up until now they elicited tidal waves of attention.

It felt pretty good.

Those good feelings, though, morphed into something else within a couple days. First, there came the fear of saying something wrong while more people were paying attention. That fear of negative approbation is nothing new or special, but it was certainly heightened. What was more disconcerting, however, was how the anticipation of attention, or more importantly possible lack thereof, crept into the back of my mind as I sat down to write future posts and tweets.

Here’s a an interesting phenomona: once you have enough followers on twitter, the lack of likes/retweets on anything you write becomes recognizable as implicit disapproval. You know what you wrote was put in front of a couple thousand people and yet nearly none of them felt it warranted a tenth of a second click. It stings.

That sting from the absence of approbation changes the incentives in front of you, maybe for some even more than the initial serotonin-dump from previous bursts of positive attention. You feel the pull to write about the things that got attention before, to write in the same manner or mood. To give the customers what they want.

And the customer that matters most is the part of your brain that wants to re-live the thrill of thousands of strangers telling you that you are good and smart and pretty and are totally worth keeping around. This is an addiction. Now there is, of course, no shortage of people calling social media an addiction. What I would like to argue is that it is a particularly dangerous addiction because it is a perfectly rational addiction.

A Rational Addiction Model of Attention

I’ll skip any real math, but indulge me a moment of framing:

A simple model of rational addiction to attention starts with three inputs: positive approbation (P), negative approbation (N), and total attention (T), where T = P + N.

Now lets assume that your utility is increasing with P and decreasing with N, while also increasing with T. That’s all pretty uncontroversial for humans. Let’s also assume that negative attention is easier to reliably generate than positive attention (i.e. trolling is harder to ignore). To put a little structure on it, we’ll assume that they are all substitutes, but with different weights .

U = T^w1 + P^w2 – N^w3

What that means is that people have an incentive to pursue attention, but how they allocate their efforts across plays for positive and negative attention will depend on how much they weight the cost of negative attention relative to what they gain from total attention.

Here comes the twist, though.

What if T is not the absolute total attention you are receiving today, but instead T is the total attention you are receiving today relative to the average attention you have received in the past, the level of attention you have become accustomed to?

U = (T- T_mean)^w1 + P^w2 – N^w3

Well now you’re on a hedonic treadmill, but for attention instead of wealth or luxury. Your brain has grown used to a rush of serotonin from the attention of millions of strangers. You’re like an adrenaline junkie, but instead of jumping out airplanes you’re trolling public figures and latching on to “Twitter’s main character” everyday.

What’s interesting about this model of rational addiction, however, is how quickly you can find yourself pursuing negatiive attention. ostensibly producing negative utility (i.e. actively making yourself unhappy) by pursuing negative attention because the total cost of that negative attention to you is less than the even costlier option of no one paying attention at all. Would you log on to twitter everyday if if cost you a hundred dollars? You would if not logging on cost you ten thousand. Same thing for those who are rationally addicted. What started out as a positive reaction to a small number of well-received insights has created a utility monster trolling the world in a desperate plea for negative attention in the hopes that it will grant the slightest reprieve from the icy desperate loneliness inside that haunts my every moment.

I’m fine. Really. I’m making a point.

When we talk about the problems of social media for mental health, we tend to focus on bullying, dysmorphic self-images, and the creation of false standards of value. I think all of those problems are extremely real, but they also seem like things that can be addressed with policies, oversight, or cultural adaptation. What I want us to consider is that attention at this scale is something that is so baked into the construct of social media that problems emerge from perfectly rational engagement by otherwise well-intending people. I’ve previously tried to model the loneliness that can come with being extermely online, but this in some ways is actually deeper.

What if, for most of us, the only way to win at social media is not to play?