Not my usual topic of course but Humble Bundle has the most amazing bargain until the end of January on 39(!) Diskworld Novels: https://www.humblebundle.com/books/terry-pratchetts-discworld-harpercollins-books the novels fall into what you might describe as the comic fantasy genre and if you like that genre, this is an amazing bargain on some of the best books in … Read more
In my previous blog entry, I tried to explain why absolute risk reductions was the right number to look at. The trouble is absolute reduction is expressed as a percentage and people generally hate percentages and usually need to do some further mental gymnastics to process the information. So statisticians in the 1980’s came up … Read more
The recent SELECT study broadcast that using Wegovy size (2.4mg/weekly) dosages of Semaglutide for three years would reduce the risk of cardiovascular men events among some pretty seriously ill people by 20%. Unfortunately, when you dig deeper, what you discover is that what the study really showed is that if you treated 1,000 of these … Read more
https://slate.com/technology/2022/01/rapid-testing-covid-math-false-negatives-sensitivity.html But they cut my draft down dramatically. I wanted to add a discussion of what is called “positive predictive value” (PPV) i.e. the answer to the question “if you test positive, do you have the disease?” If a disease is relatively rare (alas not Omicron) even a positive result with a very specific test … Read more
As a precaution against what will surely be misreported by the press, here is a thought experiment with some numbers. The UK is reporting a doubling time of 2 days. Suppose there are 100 Omicron cases now, then in 2 weeks we would have 12,800 people testing positive on a given day if everyone was … Read more
Suppose you see a headline that says something like: “50% of our 100,000 new Covid cases were among the vaccinated”? Should you be concerned that the vaccine isn’t working anymore? The answer is: absolutely not – well, not without a lot more information. This statement is an example of using numbers to confuse rather than … Read more
I haven’t written about the pandemic in a while because, well, we have vaccines that work pretty damn well – even against the incredibly contagious delta variant. People just need to get vaccinated. I could do a post every day that just repeats that 500 times I suppose. But I was talking to someone and … Read more
I was just about to write a blog about how insane this claim is. If anything, the numbers show that the AstraZeneca vaccine lowers the risk of blood clots but the great Weekend Editor beat me to it. So, even if you have to skip the great statistical stuff in his blog, just read his … Read more
We now have a one-dose vaccine that we are confident is reasonably effective on younger people while, as usual, being somewhat less confident that it is effective on older people. Moreover, not only does the J&J vaccine require only one dose, it has no fancy requirements for transporting it. Even more, reasoning by analogy with … Read more
As I write this more than the equivalent of a 9/11 catastrophe happened yesterday (12/10). It’s horrible and it’s going to get worse. The head of the CDC predicts this level of deaths for the next 60-90 days and even the conservative model used by the IHME says it is likely we will have more … Read more