Harvard Demonstrates How Not To Do Science In New Self-Confirming Mask Paper

All models only say what they are told to say

Now I ask you: If you have a computer and want to do a simulation, you must write the code for it.

Yes?

It doesn't matter what form this code is, but it has to be something. It must contain, at some level, instructions like "If X then Y", and so forth. It must take inputs, work on them by rules you construct, you command, and you direct, and create from the input and rules certain outputs.

So help me here. Suppose you wrote code that specified, "If a kid wears a mask then he has a small chance of becoming infected", and also specified, "If a kid does not wear a mask then he has a larger chance of becoming infected". You run your code and it outputs certain numbers. Numbers which are the logical result of the rules you set. Numbers from which we deduce these two statements:

1. Kids who wear masks have a small chance of becoming infected;

2. Kids who do not wear masks have a larger chance of becoming infected.

Still with me? Now, do you suppose it is the height of scientificity to scientifically declare that your science study research has scientifically discovered "Kids who wear masks have a small chance of becoming infected" and "Kids who do not wear masks have a larger chance of becoming infected"?

If you say yes, you can find employment at Harvard.

Here's the tweeted press release from the Harvard T.H. Chan School of Public Health (it's a thread):

A new study says it is too soon to lift mask mandates in schools, citing a mathematical model based on COVID-19 vaccination rates and case rates...

“This study emphasizes that it is important for schools to set clear objectives for what they want to achieve from their policies around masks and other mitigation measures,” said lead author and Harvard Chan School PhD candidate @jc_giardina (@decisionscience)...

Senior author @aciaranello says the model offers a "systematic, mathematical approach" that can be tailored to decision-makers’ goals -- such as preventing all in-school transmissions or minimizing absences to promote in-person learning...

Researchers concluded that, even with varying goals, local COVID-19 case rates should be far below those seen at this point in the pandemic to safely lift mask mandates without risking increased transmission within schools.

The <em>peer-reviewed</em> paper is "Model-Estimated Association Between Simulated US Elementary School–Related SARS-CoV-2 Transmission, Mitigation Interventions, and Vaccine Coverage Across Local Incidence Levels" by Giardina and others, and is in JAMA.

Here's their Conclusion:

In this study, in-school mitigation measures (eg, masks) and student vaccinations were associated with substantial reductions in transmissions and infections, but the level of reduction varied across local incidence.

They have declared "Kids who wear masks have a small chance of becoming infected". Let's see how they came to that conclusion.

In the Introduction they state, "While multiple studies indicate that masks are effective at mitigating the transmission of upper respiratory viruses...Masks are physiologically safe". Later, they allow the possibility that masks might slow learning. And then ignore it.

They have sentences like this:

With the Delta variant and 0% student vaccination, if removing masks (or other mitigation measures) was associated with a decrease in mitigation effectiveness to 30% (mitigation group A midpoint), decision-makers who seek to keep the monthly probability of in-school transmission less than 50% could remove masks at or below an observed local incidence of approximately 2 cases per 100?000 residents per day (Figure 1A).

Writing ability is not required of scientists.

It's not clear how they hid their discovery until we reach the "supplementary" material. (I complain frequently more and more papers hide mountains of crud and relevant detail in "supplementary" material. Papers, in effect, often use the Appeal to Authority fallacy.)

Anyway, there it is, bold as e-girl asking for donations, in "eMethods 2. Sources for Mitigation Ranges" (my emphasis below).

Interventions in A, plus universal masking (a policy of masking all students and educators/staff): 60-80% assumed effectiveness.

The interventions in A are "Simple ventilation and handwashing (open windows if present, portable air filters, maintain existing HVAC systems, and regular handwashing): 20-40% assumed effectiveness".

Did you see the word assumed? Did you see it was used twice?

And did you see the conclusion? "Mitigation measures [such as masking] or vaccinations for students substantially reduced these modeled risks" of "in-school SARS-CoV-2 transmission."

In other words, our Harvardites began by assuming masks work. They then ran a model which assumed masks work. The model said, as it was told to, masks work.

Their press office, I remind you, then said, "A new study says it is too soon to lift mask mandates in schools, citing a mathematical model based on COVID-19 vaccination rates and case rates."

This is not science. This is video games.

A reminder: all models only say what they are told to say. Say that out loud!

Buy my new book and learn to argue against the regime: Everything You Believe Is Wrong.

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