Basic epidemic math

We are living in an epidemic of armchair epidemiology, and far be it for me to contribute by giving my own feverish take as an expert of an unrelated field. Therefore, I solemnly swear that I will make no predictions about the present pandemic. I am not paid enough to make such predictions–and if you did pay me I would consider it my professional duty to find you a better expert.

What I can do for free, is read up on basic epidemiology, and digest the maths for you, dear reader. My sources: Wikipedia’s article on mathematical modeling and compartmental models, and some lecture notes I found. My expertise: during my PhD in physics, I frequently worked models like the one I’m about to discuss, only with electrons instead of people.

The SIR Model

The very first epidemiological that one learns about, is the so-called SIR model. This model divides the population into three groups (“compartments”): susceptible (S), infected (I), and recovered (R). Susceptible people are those who could be infected; infected people are those who are currently infectious; recovered people are those who are no longer infectious, and are immune to infection. “Recovered” can be a bit euphemistic, since one method of “recovery” is dying. Another method of “recovery” is by developing symptoms strong enough that the victim knows to quarantine themself (becoming less infectious).

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MBTI: A lukewarm analysis

MBTI, or the Myers-Briggs Type Indicator, is probably the most popular personality test. It contains four axes: Introverted/Extraverted, iNtuitive/Sensing, Thinking/Feeling, Judging/Perceiving. If you take the test, you may be assigned one of 16 personality types, for instance I would be INTJ.

The MBTI is regarded as pseudoscience, perpetuated by the popular consciousness and HR departments rather than academic research. One time I asked a personality psychologist and she said it was just so far off from reality that nobody even bothered talking about it. Psychologists prefer to talk about another personality model, called the Five Factor Model, also known as The Big Five. This has five axes, labeled Openness, Conscientiousness, Extraversion, Agreeableness, and Neuroticism (OCEAN).

I’ve often remarked that although the Five Factor Model is supposedly more scientific, it’s clearly a lot less compelling. And isn’t that something? I couldn’t honestly say that I find astrology compelling, or ear candles compelling, but the MBTI, now that’s some yummy pseudoscience. I have some remarks on what makes MBTI a pseudoscience, what makes it compelling, and what its problems are.

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“Cat Person or Dog Person?” survey explained

Picture of a cat with sciencey stuff. "Survey says 75% are cat people ... and 25% are wrong"

Several weeks ago, I published the “Cat Person or Dog Person?” survey.  It’s a silly survey that asks the same question over and over again in different ways, and then you see the results.  It’s basically an interactive art piece, and your interpretation of it is as valid as mine.

Now that several weeks have passed, I’m going to explain some of the thought process behind the survey.  This should be thought of as “explaining the joke”–the survey was funny, this explanation will not particularly (cat meme excepted).

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Stop supporting nuclear power

A powerful way to convince people of a policy, is to get them to believe they understand the policy’s disadvantages. People believe they understand the disadvantages of nuclear power: radioactive waste, and the possibility of catastrophe. Skeptical/sciencey people tend to think these disadvantages are small, because they know people often give too much weight to highly unlikely outcomes. But in fact, the main thing holding back nuclear power, is that it’s not economically competitive.

Public understanding of nuclear power is based on decades of political debate, with one side arguing that nuclear power is much cleaner than the alternatives, and the other side pointing to catastrophes like Chernobyl or Fukushima. I recall being taught these advantages and disadvantages in grade school science classes. They were also encoded into Sim City. But in the real world, the advantages and disadvantages of different energy sources are not timeless. They depend on the details of the technology. It is not possible to understand a complex and ever-changing issue based on what you were taught in grade school.

If you take nothing else away, I would like to at least persuade you of this: a) you don’t understand the disadvantages of nuclear power as well as you thought, and b) your position of “more nuclear power” should be updated to “nuclear power is an option that experts should consider”.  If you’d like to learn more, read on.

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The black hole: Zoom in, enhance!

A few days ago, scientists announced the very first real image of a black hole (as opposed to one of those “artist’s conception” images that you see everywhere).

blurry ring of light

Black hole Messier 87 (aka M87) (credit)

This was a very nice surprise, because I was not aware any such project was underway, and I would have thought the obstacles were too great.  The main problem with imaging black holes is that black holes are really far away.  You would have to “zoom in and enhance” many many times to get the image above.  Let’s compare it to other examples of extreme zooming.

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Measuring musical dissonance

An empirical approach

When we hear two musical notes played together (either in succession, or simultaneously), we often characterize those notes as “dissonant” or “consonant”. But instead of having a sharp dichotomy between dissonance and consonance, it might be more useful to speak of a spectrum between the two. Then, the question before us is how to quantify the dissonance of any pair of notes.

12tone is a cool music theory channel, and he recently published a video discussing the solution thought up by the 18th century mathematician Leonhard Euler. I include the video below, but be warned that I’m going to trash Euler’s answer. I believe that any measure of musical dissonance must, at some point, refer to empirical observations of dissonance. Euler’s answer relies on mathematical supposition, and thus I would deride it as numerology.

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Ethical review of academic hoaxes

I learned from PZ that Peter Boghossian is under ethical investigation for his “grievance studies” hoax.  Peter Boghossian was one of three authors of the hoax, but the other two (James Lindsay and Helen Pluckrose) do not hold academic positions, so are unlikely to be sanctioned.

An institutional review board (IRB) concluded that by involving journal editors and reviewers, they were conducting research on human subjects, and per standard policy they should have gotten IRB approval before beginning.  Everyone–including Boghossian’s defenders–suspects that if he sought IRB approval, he would have been rejected.

Note, there are plenty of experiments that deceive human subjects and still get IRB approval, but I suspect this particular hoax would encounter problems beyond mere deception.  They were undergoing peer review, which is rather arduous labor to get from non-consenting subjects.  The hoax also involved fabricating data, and the IRB decision on that matter is still pending.  I would also say that the hoax did not have much scholarly merit, which is a legitimate consideration for these ethical reviews.

Boghossian’s defenders, of course, are spinning a “martyr for free speech” narrative.  If the target of his hoax were something more acceptable, would he still have been criticized on ethical grounds?

Well, actually…

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