https://slate.com/technology/2021/12/omicron-exponential-growth-math-chess.html
Looking at stuff through the eyes of a mathematician – Gary Cornell's blog
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You need to correct that article ASAP. You literally reversed sensitivity and specificity. It is deeply misleading, in fact rapid tests have a much better negative predictive value than positive predictive value.
A test with no false positives has 100% positive predictive value.
PPV is defined as TP/(TP +FP)If FP = 0, then PPV is 1
(It is very unusual I admit for a test to have no false positives…)
I wanted to add a discussion of PPV and NPV but they said no. It will hopefully be in another article.