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This is a flawed story from the NYT because it makes a basic logical mistake: it does not distinguish between necessary and sufficient conditions. https://www.nytimes.com/interactive/2020/08/14/opinion/politics/covid-school-reopening-guidelines.html">https://www.nytimes.com/interacti...
So, what& #39;s the difference?
A necessary condition is something that needs to be satisfied in order to get a result. It& #39;s really the *absence* of the necessary condition that tells us something, not its presence.
A necessary condition is something that needs to be satisfied in order to get a result. It& #39;s really the *absence* of the necessary condition that tells us something, not its presence.
For example, being born in the US is a necessary condition to become president. If you were born in the US, we don& #39;t really know much more about your prospects for the presidency. If you were NOT born here (like me), then we know you won& #39;t be president.
A sufficient condition tells us something when it *is* present, not when it& #39;s absent; e.g., winning the majority of the electoral votes is sufficient to become president. It& #39;s not the only way though (LBJ, Ford, etc). The absence of a sufficient condition does not tell us much.
OK, so back to the NYT story and school reopening. It claims that if your cases are low and testing is high you could return, but those are just necessary conditions, not sufficient ones, so we cannot say that if you meet them you could reopen.
In my own town, our cases and testing probably meet those conditions, BUT our buildings have space issues and, even more, ventilation and HVAC issues. Oh, and no one has a clear idea what hybrid learning is or how it works best.
In other words, there are necessary conditions that need to be met for schools to open in addition to cases & testing. Ticking off 2 of them is not justification to say a school *could* open, so the NYT story is almost certainly too optimistic.
