How many people have cancer?

Factual Questions
21

Thank you. Those are the numbers I’ll use.

22

I’ve had cancer every day since I was 20-something. I’m 65 now. Every few months the dermatologist scrapes off some more from someplace. I can see a couple of spots right now while typing that my experienced but utterly amateur eye diagnoses as Basal Cell Carcinoma.

I’d suggest the OP would do far better to pick a different topic for teaching about Bayes, than the very vague very woolly idea of “has cancer”. Probability, and especially probability in school, is wooly enough without picking vague things to talk about.

This smells to me a lot like

Given an urn with an unknown number of balls of each and every RGB color from #000000 to #FFFFFF how many are greenish?

First off, define what “green” means in that context. Then define “ish”. Then and only then can we begin to compute.

23

We’re not researching methodology, type 1 vs type 2 errors, etc. I just wanted some numbers with some justification rather than pull numbers out of nowhere. I’m not teaching oncology research here.

24

I gave you those numbers in the second post of the thread.

25

And you’ll notice my posts were all in response to people keeping this thread alive after that. I’m using Kent Clark’s number because it is in the range you gave but is specific enough for what I need.