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posted ago by cartoonericroberts ago by cartoonericroberts +32 / -0

So I came across an article, "40% of local Covid-19 cases are in the vaccinated. What does that say about the vaccines?", https://archive.is/Y8dx5. It states 40% of local cases are in the vaccinated but gives the following to support that this doesn't reflect poorly on the vaccine:

The state health department said that Wednesday’s study found “unvaccinated New Yorkers were 11 times more likely to be hospitalized and eight times more likely to be diagnosed with COVID-19 than those who were fully vaccinated.”

So, 40% of cases are in the vaccinated and Syracuse has a 60% vaccination rate. Let's do the math P(A|B) = P(B|A)P(A)/P(B). The probability of X is written P(X). The probability of X given Y is written P(X|Y). A is 'diagnosed with covid'. B is vaxxed. !B is not vaxxed. We don't know what P(A) is but that's okay, we will set it to x. P(A|B) = .4 * x / .6 and P(A|!B) = .6 * x / .4. The ratio of covid given not vaxxed to covid given vaxxed is P(A|!B)/P(A|B), (.6x/.4)/(.4x/.6) so .36/.16 or 9/4, 2.25. For the eight times statement to agree with with the reality the journalist has observed the vaccination rate would have to be 85% which would be an impossible number even if the vaccine was mandatory.

While I don't expect journalists to know bayes law I would expect them to at least find the numbers unlikely and maybe talk to a statistician instead of just spewing them out uncritically, but that would assume journalist was anything more than PR for the state.