If the false positives are 10% of the people who have NOT had CV19 that's .10 x 95 people = 9.5 people. Add to that the 5% eg 5 people who really are positive and you have 14.5 people that test positive.

So 9.5/14.5 ~ 65% false positives. (He might have included false negatives to get the extra 5 %.) 10% of 5 is .5 so subtract that from the base. 9.5/14 ~ 68% fudging a bit are we NYT?

But here's my problem. Who says that the false positives are 90%? he doesn't cite any studies, he's just using his vast NYT's intelligence to explain basic statistics to us. I would hope that tests would provide a 99% or a 99.999% false positive rate. false positives and false negatives aren't necessarily equal either. Kind of a strawman argument.

So yeah, learn statistics everybody, but this doesn't tell you a thing other than to lecture you to, well learn statistics. Note that this is an opinion piece not an article.

[Post edited by `lag at 05/13/2020 1:24PM]