Category: Uncategorized
Tuesday assorted links
1. Revised look at IHME epidemiological predictions. And public code for the Imperial College model.
2. Very good Derek Thompson piece on the evolution of retail (Atlantic).
3. Pandemic urbanism bibliography.
4. Mulligan, Murphy, and Topel on Covid-related issues. They think like economists.
5. The role of different occupations in transmitting Covid-19.
6. Osterholm and Olshaker on testing, good piece (NYT).
7. Coronavirus spreading in Africa more slowly than expected (FT but not gated).
8. Forced isolation.
Early detection of superspreaders by mass group pool testing
Most of epidemiological models applied for COVID-19 do not consider heterogeneity in infectiousness and impact of superspreaders, despite the broad viral loading distributions amongst COVID-19 positive people (1-1 000 000 per mL). Also, mass group testing is not used regardless to existing shortage of tests. I propose new strategy for early detection of superspreaders with reasonable number of RT-PCR tests, which can dramatically mitigate development COVID-19 pandemic and even turn it endemic. Methods I used stochastic social-epidemiological SEIAR model, where S-suspected, E-exposed, I-infectious, A-admitted (confirmed COVID-19 positive, who are admitted to hospital or completely isolated), R-recovered. The model was applied to real COVID-19 dynamics in London, Moscow and New York City. Findings Viral loading data measured by RT-PCR were fitted by broad log-normal distribution, which governed high importance of superspreaders. The proposed full scale model of a metropolis shows that top 10% spreaders (100+ higher viral loading than median infector) transmit 45% of new cases. Rapid isolation of superspreaders leads to 4-8 fold mitigation of pandemic depending on applied quarantine strength and amount of currently infected people. High viral loading allows efficient group matrix pool testing of population focused on detection of the superspreaders requiring remarkably small amount of tests. Interpretation The model and new testing strategy may prevent thousand or millions COVID-19 deaths requiring just about 5000 daily RT-PCR test for big 12 million city such as Moscow.
Speculative, but I believe this is the future of our war against Covid-19.
The paper is by
Monday assorted links
1. “We also looked Iceland-scale mass population testing (i.e. 0.7% of population per day). Such testing would be very helpful for monitoring the epidemic, but unsurprisingly it had a negligible impact on reducing transmission, because cases would be detected too late (if at all)”, link here.
2. Which workers bear most of the burden from social distancing policies?
3. This 1,000-Year-Old Mill Has Resumed Production Due to Demand for Flour.
5. BMI is very hard to predict, even with an impressive data set of socioeconomic and genetic factors.
6. Graph of excess deaths in various locales, recommended, and Sweden far from the worst. Bergamo ouch.
7. Was Portugal early to take care of the nursing home problem? And Connecticut looking for a nursing home solution (WSJ).
8. Vaccine update.
9. Solving for the equilibrium: “Some of the millions of British workers furloughed during the coronavirus lockdown will be encouraged to take a second job picking fruit and vegetables, the government has said. Giving the daily COVID-19 briefing, Environment Secretary George Eustice said only a third of the migrant workers who normally picked fruit and vegetables were currently in the country.”
10. ComedyCellar podcast with me, Coleman Hughes, Yascha Mounk, others, audio / pod: http://riotcast.com/thecomedycellar and the link to youtube: https://www.youtube.com/watch?v=fNG1FsUdXDw.
11. Which retailers generate the most physical interactions? (Big, internationally known chains) Might the same be true for restaurants?
12. “The scenario of one million Covid-19 deaths is similar in scale to the decades-long HIV/AIDS and opioid-overdose epidemics but considerably smaller than the Spanish Flu of 1918. Unlike HIV/AIDS and opioid epidemics, the Covid-19 deaths will be concentrated in months rather than spread out over decades.” Link here.
13. Spanish flu closings were short in duration and didn’t help much.
14. What community colleges do and do not know. And a list of colleges’ plans.
The lockdown culture that is Singapore
S’porean man charged in court for leaving home 30 minutes before quarantine ended to get breakfast
And:
According to CNA, Tay is accused of leaving his home in Choa Chu Kang between 11:30am and 12pm, half an hour before his quarantine ended.
He thus breached his quarantine order by leaving his home to go to his neighbourhood shopping mall for breakfast without getting the permission of the Director of Medical Services, said the MOH release.
And:
The day prior, Thursday, Apr. 23, 34-year-old Alan Tham was sentenced to six weeks’ imprisonment for breaching his Stay-Home Notice (SHN) to eat bak kut teh.
To be clear, I am fine with Singapore doing this, but it hard to imagine the United States enforcing quarantine with the same vigor. And on the other side, I might risk prison for laksa, but for bak kut teh?
For the pointer I thank Tuvshinzaya. and Jeet Heer asks:
I have to confess I’m becoming more pessimistic since I don’t see much signs that most countries outside Asia & the Pacific are developing the testing-tracing-isolation capabilities needed. Am I wrong about this?
Sunday assorted links
1. How many young people would volunteer to take a Human Challenge vaccine?
2. How much does tourism inflow account for coronavirus heterogeneity?
3. Christopher Phelan argues for relaxing mass quarantine.
5. Puffins. And celebrities have never been less entertaining.
6. Short history of Iceland coronavirus policy, quite interesting. And Netflix continues production in Iceland (and South Korea).
7. Russians mimicking famous art works (NYT).
Saturday assorted links
2. Why isn’t Florida doing worse?
3. Podcast with Chris Murray on the IHME model (have not heard it yet).
4. Iceland update, lots of data, useful pictures.
5. A French cluster: “The overall IAR was 25.9% (95% confidence interval (CI) = 22.6-29.4), and the infection fatality rate was 0% (one-sided 97.5% CI = 0-2.1).”
Social distancing should never be too restrictive
That is the topic of a new paper by Farboodi, Jarosch, and Shimer, published version in here. They favor ” Immediate social distancing that ends only slowly but is not overly restrictive.” Furthermore, they test the model against data from Safegraph and also from Sweden and find that their recommendations do not depend very much on parameter values.
Here is an excerpt from the paper:
…social distancing is never too restrictive. At any point in time, the effective reproduction number for a disease is the expected number of people that an infected person infects. In contrast to the basic reproduction number, it accounts for the current level of social activity and the fraction of people who are susceptible. Importantly, optimal policy keeps the effective reproduction number above the fraction of people who are susceptible,although for a long time only mildly so. That is, social activity is such that, if almost everyone were susceptible to the disease, the disease would grow over time. That means that optimal social activity lets infections grow until the susceptible population is sufficiently small that the number of infected people starts to shrink. As the stock of infected individuals falls,the optimal ratio of the effective reproduction number to the fraction of susceptible people grows until it eventually converges to the basic reproduction number.
To understand why social distancing is never too restrictive, first observe that social activity optimally returns to its pre-pandemic level in the long run, even if a cure is never found. To understand why, suppose to the contrary that social distancing is permanently imposed, suppressing social activity below the first-best (disease-free world) level. That means that a small increase in social activity has a first-order impact on welfare. Of course, there is a cost to increasing social activity: it will lead to an increase in infections. However,since the number of infected people must converge to zero in the long run, by waiting long enough to increase social activity, the number of additional infections can be made arbitrarily small while the benefit from a marginal increase in social activity remains positive.
Recommended, one recurring theme is that people distance a lot of their own accord. That means voluntary self-policing brings many of the benefits of a lockdown. Another lesson is that we should be liberalizing at the margin.
If I have a worry, however, it has to do with the Lucas critique. People make take preliminary warnings very seriously, when they see those warnings are part of a path toward greater strictness. When the same verbal or written message is part of a path toward greater liberalization however…perhaps the momentum and perceived end point really matters?
For the pointer I thank John Alcorn.
Big G
Yes, that is the title of a new paper and it is excellent indeed. Lydia Cox et.al bring you a fresh and original look at some properties of government spending:
“Big G” typically refers to aggregate government spending on a homogeneous good. In this paper, we open up this construct by analyzing the entire universe of procurement contracts of the US government and establish five facts. First, government spending is granular, that is, it is concentrated in relatively few firms and sectors. Second, relative to private expenditures its composition is biased. Third, procurement contracts are short-lived. Fourth, idiosyncratic variation dominates the fluctuation of spending. Last, government spending is concentrated in sectors with relatively sticky prices. Accounting for these facts within a stylized New Keynesian model offers new insights into the fiscal transmission mechanism: fiscal shocks hardly impact inflation, little crowding out of private expenditure exists, and the multiplier tends to be larger compared to a one-sector benchmark aligning the model with the empirical evidence.
Via the still excellent Kevin Lewis.
Are humans constantly but subconsciously smelling themselves?
Here is the opening of a lengthy abstract of a new paper by Ofer Perl, et.al., and it may help explain why it is so hard to avoid touching your face:
All primates, including humans, engage in self-face-touching at very high frequency. The functional purpose or antecedents of this behaviour remain unclear. In this hybrid review, we put forth the hypothesis that self-face-touching subserves self-smelling. We first review data implying that humans touch their faces at very high frequency. We then detail evidence from the one study that implicated an olfactory origin for this behaviour: This evidence consists of significantly increased nasal inhalation concurrent with self-face-touching, and predictable increases or decreases in self-face-touching as a function of subliminal odourant tainting. Although we speculate that self-smelling through self-face-touching is largely an unconscious act, we note that in addition, humans also consciously smell themselves at high frequency.
File under Questions that are Rarely Asked, via Michelle Dawson.
Friday assorted links
1. What do we know about superspreader events? And indoor transmission in China. And what Arnold Kling has come to believe.
2. “We show irradiance and in particular solar zenith angle in combination with cloudopacity explain COVID-19 morbidity and mortality growth better than temperature.” Interesting, though still more interpretation is needed there.
3. Covid-19 in Haiti. And what is Wuhan like right now?
4. In Germany, they consult humanities scholars about how to end the lockdown. And from a French philosopher. And we need blogs back for the pandemic.
5. “Southern New Hampshire University, known for being on the cutting edge of collegiate learning, plans to slash tuition for incoming freshmen as it drastically revamps how it conducts on-campus learning beginning in the fall.As part of the changes, tuition will be cut 61%, from $31,000 to $10,000 starting in the 2021-2022 academic year.” Link here.
6. No strong statistical evidence for the BCG vaccine claim.
7. Is the internet economy going to crash as the real economy shrinks? Several interesting points in that one.
8. de Rugy and Kling on government-backed lines of credit for small business.
9. Bundled insurance markets in everything: “COVID-19 insurance comes free with food delivery in Hong Kong now.”
10. Thread on the meaning of the new NY results.
11. Toward a theory of Tyrone.
12. Test different recovery levers. And Zeynep speaks sense.
How things are, in a few short words
If we keep the economy closed at current levels, it will continue to decay, and at some point turn into irreversible, non-linear damage. No one knows when, or how to model the course of that process. That decay also will eat into our future public health capacities, and perhaps boost hunger and poverty around the world.
If we keep people locked up at current levels, fewer of them will be exposed to the virus, and in the meantime we can develop better treatments, and also improve test and trace capabilities. No one knows how quickly those improvements will come, or how to model the course of that process, or how much net good they will do.
The relative pace of those two processes should determine our best course of action. No one knows the relative pace of either of those two processes. Yet commentators pretend to be increasingly knowledgeable, moralizing based on the pretense of knowledge they do not have.
That is where we are at! And here is my earlier post Where We Stand.
The essential Ben Thompson on isolation and quarantine
…while I have written about Taiwan’s use of cellphone-enforced quarantines for recent travelers and close contacts of those infected, I should also note that every single positive infection — symptomatic or not — is isolated away from their home and family. That is also the case in South Korea, and while it was the case for Singaporean citizens, it was not the case for migrant workers, which is a major reason why the virus has exploded in recent weeks.
Here’s the thing, though: isolating people is hard. It would be very controversial. It would require overbearing police powers that people in the West are intrinsically allergic to. Politicians that instituted such a policy would be very unpopular. It is so much easier to let tech companies build a potential magic bullet, and then demand they let government use it; most people wouldn’t know or wouldn’t care, which appears to matter more than whether or not the approach would actually work (or, to put it another way, it appears that the French government sees privacy as a club with which to beat tech companies, not a non-negotiable principle their citizens demand).
So that is why I have changed my mind: Western governments are not willing to take actions that we know work because it would be unpopular and controversial (indeed, the fact that central quarantine is so clearly a violation of liberties is arguably a benefit, because there is no way people would tolerate it once the crisis is over). And, on the flipside, that makes digital surveillance too dangerous to build. Politicians would rather leverage tech companies to violate liberty on the sly, and tech companies, once they have the capability, are all too willing to offload the responsibility of using it wisely to whatever government entity is willing to give them cover. There just isn’t much evidence that either side is willing to make hard choices.
That is from Ben’s Stratechery email newsletter, gated but you can pay to get it. There is currently the risk that “test and trace” becomes for the Left what “chloroquine” has been for Trump and parts of the political right — namely a way to make otherwise unpalatable plans sound as if they have hope for more than “develop herd immunity and bankrupt the economy in the process.”
To be clear, I fully favor “test and trace,” and I’ve worked hard to help fund some of it. That said, I wonder if we will anytime soon reach the point where it is a game changer. So when people argue we should not reopen the economy until “test and trace” is in place, I increasingly see that as a kind of emotive declaration that others do not care enough about human lives (possibly true!), rather than an actual piece of advice.
Covid-19 liability reform for the eventual reopening
That is the topic of my latest Bloomberg column, here is one excerpt:
If an infected but asymptomatic worker shows up at work and sickens coworkers, for example, should the employer be liable? The answer is far from obvious. Liability exists not to shift unmanageable risk, but rather to induce management to take possible and prudent measures of precaution.
Another problem with liability law in this context is that the potential damages are high relative to the capitalization of most businesses. Covid-19 cases often pop up in chains; there have been many cases from a single conference, or in a single church choir, or on a single cruise ship. If a business or school is host to such a chain, it could be wiped out financially by lawsuits. In these cases the liability penalties do not have their intended deterrent effect because the money to lose simply isn’t there…
Another problem with liability in this setting has to do with jury expertise. Are random members of the public really the best people to determine acceptable levels of Covid-19 risk and appropriate employer precautions? Juries are better suited for more conventional applications of liability law, such as when the handyman fixing your roof falls off your rickety ladder. Given the unprecedented nature of the current situation, many Covid-19 risk questions require experts.
Finally, there is the issue of testing. Businesses could be of immeasurable help by testing their employees for Covid-19, as additional testing can help limit the spread of the virus (if only by indicating which workers should stay home or get treatment). Yet the available tests are highly imperfect, especially with false negatives. If businesses are liable for incorrect test results, and their possible practical implications, then business will likely not perform any tests at all, to the detriment of virtually everybody.
I recommend modest liability for some sectors, and zero liability, bundled with a New Zealand-like accident compensation system, for other sectors. And of course some very dangerous sectors should not be allowed to reopen at all, though I am more sympathetic to regional experimentation than are some people on Twitter.
Thursday assorted links
1. Why is the Eastern European response better? (WSJ) And how are Swedish hospitals doing?
2. Further doubts on the LOA and Santa Clara serology stories, it now seems they really do not establish any particular results.
3. Why a vaccine will be tough, a depressing thread. And are China’s early patients shedding coronavirus?
4. Ezra Klein on why we can’t build things.
5. Why two decades of pandemic planning failed.
6. New Joshua Gans book, Economics in the Age of Covid-19, MIT Press.
7. Hollis Robbins on why some saw this coming before others.
8. New Becker-Friedman Center podcast on Pandemic Economics.
9. Various forms of presenting state-level data. What exactly is going on with Ohio?
10. Are we prepping for vaccine state capacity?
11. Department of Why Not?: “Former Labradoodle breeder tapped to lead U.S. pandemic task force.”
12. The couple that meets on the German-Danish border during lockdown (NYT).
13. The Fed and saving cities (NYT).
Why the low status of opposition to child abuse?
Michael Kaan emails me:
Hi Tyler, I’m a healthcare professional in Canada and a long-time reader of your blog. For the past couple of years, observing the culture wars and various elections, I’ve noticed that child abuse is an extremely rare topic among the cultural left: the highly visible progressive segment that drives wokeness, is culturally powerful, etc. You know what their dominant concerns are. (On the right it’s basically non-existent.)
While there’s nothing obviously wrong with their attention to sexual and racial discrimination, the energy put into it is disproportionate to the massive social cost of child abuse. Rates vary around the world, but in general it looks like about 30% of all children globally suffer some sort of serious maltreatment each year, often many times a year, repeated over multiple years.So one can easily estimate that billions of people have experienced this. In other words, more people have been abused as children than have experienced war, famine, or epidemics.
The impact and costs of this have been measured (low academic achievement, health problems, low earnings, drug and alcohol use, etc.), and child abuse is sometimes lethal. What puzzles me is why it has no legs politically. Among the woke crowd, if child abuse is mentioned it’s usually in terms of discrimination against girls or sexual minorities. But there are really no prominent voices actively campaigning to mitigate child abuse generally.Why is this? Is it overly complex? Is the phenomenon too widely dispersed demographically, so that an evil agent group isn’t easily identified? Does its persistence foreground chronic failures of the welfare state (if that’s the case)? Is it boring?
For a start, I would note that virtually everyone is again child abuse, so opposing it doesn’t make anyone significant look worse. But I am sure there is much more to it than that.