Charley Hooper on Masks

I posted recently about the discussion between Phil Magness and Jeremy Horpedahl about mask mandates to deal with COVID-19. My sometimes co-author and former student Charley Hooper wrote the following on masks in a recent email. He’s given me permission to share it. The bottom line: the evidence in favor of masks, let alone mandates, just does not seem to be there.

Here’s Charley:

The only randomized controlled trials conducted to study the effects of wearing masks and washing hands show that those two preventative techniques don’t significantly reduce the spread of the influenza virus. In some studies they help a bit. In other studies, they hurt a bit.

“Although mechanistic studies support the potential effect of hand hygiene or face masks, evidence from 14 randomized controlled trials of these measures did not support a substantial effect on transmission of laboratory-confirmed influenza.”


Why did I mention influenza and not COVID? COVID-19 is supposed to be transmitted by the same mechanism as influenza and influenza has been around long enough to be better studied.
The Xiao study referenced above contains this shocking admission: “It is essential to note that the mechanisms of person-to-person transmission in the community have not been fully determined. These uncertainties over basic transmission modes and mechanisms hinder the optimization of control measures.” Scientist don’t have a handle on how the flu transmits throughout the community. If you don’t know that basic fact, it’s pretty hard to effectively prevent the transmission of influenza! By extension, I think it’s safe to say that scientists don’t understand how the SARS-CoV-2 virus is transmitted.
The influenza virus can last about five minutes on a human hand. (“Virus survived on hands for up to 5 min after transfer from the environmental surfaces.”) I suspect that the SARS-CoV-2 virus lasts about the same length of time on hands.
Therefore, if you don’t wash your hands but also don’t touch your eyes, nose, or mouth shortly after touching an infected surface. you should be fine.
There was one randomized controlled trial of the use of face masks to prevent COVID-19. The study was conducted in Denmark in April and May 2020. The results were not statistically significant but showed that the mask group suffered a 1.8% infection rate while the control group suffered a 2.1% rate (95% confidence intervals = 46% reduction to 23% increase due to masks). In other words, masks helped but were not a panacea.
Other studies show the benefits of wearing masks, but they are correlational, population-based studies that identify relationships but don’t necessarily prove cause and effect. I’m not saying that masks don’t work. I’m instead highlighting some of the scientific uncertainty around the use of masks. With this uncertainty, COVID absolutism is unjustified and harmful.
The rule seems to be that the less people understand about something, the more adamant their beliefs.


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My Work Continuage: A Confession

I have a confession: I continued working even though I was told not to.

I was reminded of this by this article by Mckenna Dallmeyer, Texas Senior Campus Correspondent for Campus Reform. It’s titled “State auditor demands nearly $2k from Ole Miss prof who went on ‘illegal’ strike,” Campus Reform, December 14, 2020.

Here’s what happened. I was a visiting assistant professor at Santa Clara University from September 1980 to December 1981. In the spring quarter of 1981, there was a racial incident on campus. I don’t remember what it was, but I think it was someone writing something negative about black people in a place that was visible.

The powers that be decided to cancel classes for one day so that people could go to various “teach-ins” about racial discrimination or at least contemplate racial discrimination. I was sympathetic to the cause but I thought that cancelling classes was way too big an overreaction. Of course, that wasn’t my call to make: it was my employer’s. Which is why I’m calling this a confession. Am I proud of what I did? Yes. But it was a breach of a contract and I take contracts seriously. You’ll see below that I didn’t.

I was teaching 2 classes. One was an intermediate microeconomics class with over 30 students in it. The other was an elective: a Law and Economics class with about 13 or 14 students.

I wasn’t badly behind in the intermediate micro class. But in the Law and Economics class I was behind but for a good reason. The textbook for the class was Richard Posner’s An Economic Analysis of Law. I was a fan after a very quick and somewhat cursory reading and the person who had taught the class the previous year, Henry Demmert, had used it and liked it. (He was on leave in D.C., which is why I had been hired for a year.)

So what was the good reason we were behind? It was that in working our way through the chapters, the students (all undergrads, some not even econ majors) and I were finding lots of bad economics. (And no, I can’t tell you what the mistakes were: my marked up copy was destroyed in my 2007 fire.) What started as an upset early in the course, both to the students and me, turned out to be a crusade. It was exciting each day to see if the students had found the mistake in a particular chapter–and they often had. (I’m not saying there were mistakes in every chapter: I don’t recall.)

Parenthetically, I later found Jim Buchanan’s review of Posner’s book. The review was titled “Good Economics, Bad Law.” I didn’t feel qualified to judge the law but I was quite qualified to judge the economics. I would have titled my review “Occasionally Brilliant Economics with Occasional Errors that a Good Economics Undergrad Could Have Spotted.”

Anyway, when you start working your way carefully through each chapter, you go more slowly. Halfway through the course, I had already given up on covering the whole book, but I wanted to cover at least 80% of it. The class met twice a week and so taking a whole day off–and we were told explicitly not to do makeups–would lose a half week.

So I decided to take a risk. I went into the class, which I was running around a rectangular table, and announced that I was required to cancel the next class. The announcement had created a buzz on campus and so everyone knew why.

Then I said, “Here’s my problem. We’re so far behind and I don’t want to get further behind. I’m inclined to show up for the next class.”

Then I stopped. I looked around to see if anyone would initiate. One of my students who was really enthused about the class was Charley Hooper. He was an engineering major but he had taken my intro micro and was so enthused, and got an A, that I let him into the Law Econ class without his having taken the requisite Intermediate Micro class.

Charley said, “I’ll be here.” Then the person next to him said “I’m coming.” Then “I’ll be here.” Every single person in the room said he or she would make the next class.

It was like a story I had heard in high school from one of my teachers (I think it was my 9th grade English teacher, Harvey Rosen) about a military officer who asks for volunteers for a particularly dangerous mission. He has them in a long line and tells the men that he won’t put them on the spot and so he will turn his back and whoever wants to volunteer can step forward. He gives it a minute and turns back and sees that they’re all still in a long line, with no appearance that anyone had stepped forward. Crestfallen, he asks “None of you volunteered?” One of the men answers, “No, sir. We all volunteered.”

After the students had all volunteered to come, I said, “Ok, because the issue leading to this is a racial incident, and I’m against racism, I’ll spend the last 20 minutes of the next class laying out what economists have to say about the economics of discrimination.”

We had a great discussion at the end of the next class about how free markets give employers an incentive not to discriminate on racial grounds. I gave them a verbal version of Gary Becker’s model. And we were probably the only class that met that one day at Santa Clara University.



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Dogs, Mountain Lions, and COVID-19

How dangerous are mountain lions? The data tell an interesting story. Since 1980, there have been only 13 attacks in all of California (where David and Charley live) and three people have died as a result. Compare this with attacks by dogs. Each year in California, about 100,000 dog attacks cause their victims to get medical attention. This means that California residents are approximately 180,000 times as likely to be seriously attacked by a dog as by a mountain lion. But to really compare dogs and mountain lions, we need to check our base, because there are a lot more dogs than mountain lions. With so many more dogs running around, a reasonable person would expect more dog attacks. With about 8 million dogs and 5,000 mountain lions in California, we see that there are approximately 1,500 dogs for each mountain lion. Once we check our base and correct for the numbers of dogs and mountain lions, we see that dogs are still more dangerous, and in fact, the risk of serious attack from an individual dog is about 120 times that of the risk from an individual mountain lion. Mountain lions present a daunting and ferocious image, but with so few attacks, they must have very little interest in attacking people.

This quote is from David R. Henderson and Charles L. Hooper, Making Great Decisions in Business and Life, Chicago Park Press, 2006.

The picture above is of me at the entrance to Stanford University yesterday. It reminded me of maps I saw of Germany divided into 4 zones after World War II. My friend and co-author Charley Hooper and I walked on the campus and notice a whole lot of 20-somethings walking around wearing masks even though they were typically walking alone and were not closer than 30 feet to anyone else.

They seem to fear COVID-19 the way some people fear mountain lions. My guess is that it’s a mixture of their fear and the fear of the administrators of Stanford, who seem to have taken an extremely anti-intellectual approach to the issue.

Either way, the risk to the young is extremely low. Here are data from the Centers for Disease Control as of November 12, 2020. They are for the number of deaths between February 1, 2020 and November 7, 2020. (The CDC notes that there is a lag because death counts are somewhat delayed.)

The number of Americans of age 15 to 24 who have died of COVID-19 is 410.

The number of Americans of age 15 to 24 who have died of all causes is 26,662.

Watch out for dogs, not mountain lions.

If you’re young, watch out for deaths from other causes, not COVID-19.

Postscript: What brought us to Palo Alto is my 70th birthday, which I celebrate on Saturday. Because it’s impractical right now to do what Governor Newsom did but tells the rest of us not to do, I’m not having a 70th birthday party. Instead, I’m seeing individual friends for outdoor lunches and conversation. Charley, Jay Bhattacharya, and I had a wonderful almost 3-hour outdoor lunch and conversation.


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I “Win” My Bet

In mid-March I made a bet with my good friend and co-author Charley Hooper about the number of U.S. deaths there would be from COVID-19. The terms of the bet are here. In my post, I said why I thought he might win. Of course I hoped he would win. Unfortunately, he lost. And over 100,000 U.S. residents lost much, much more.

I waited this long because he and I both agreed that there could be a substantial number of deaths of people with the disease but not of the disease. We both agree, though, that of the 133,844 U.S. deaths so far, at least 100,000 of them are due to COVID-19.

I actually had bought much of Charley’s reasoning, which is why I titled my March 16 post “My Bet on Covid-19 and Why I Might Lose.” I asked Charley last week, when we both were becoming convinced that he lost, what he attributed his loss to. He answered that he didn’t expect various governments to be so incompetent, and he highlighted the role of New York’s governor Andrew Cuomo and some other northeast governments in making the problem much worse by insisting that nursing homes admit people with the disease.


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