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0 pointsbonoboTP6y ago0 comments

Hm, I googled it now, the issue is discussed in detail here: https://math.stackexchange.com/questions/612468/how-to-forma...

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NougatRillettes6y ago

Thanks for your comments! I don't see how what is discussed here conflicts with the notation I introduced into the post, do you still believe there is a soundness issue in what I have written?

bonoboTPOP6y ago

I'm just saying that the notation of say A * X|Y * B seemed unfamiliar to me. I only know conditional notation within a P(...). Or an expectation, etc. Apparently your way of writing is used by others as well, but it may be good to know that it is not fully rigorous.

Again, there are different people preferring different presentations. I as a student was often frustrated by abused notations and was often confused by such things when trying to understand something in detail. For a more cursory and "practical" understanding it could be good enough.

kgwgk6y ago

> it may be good to know that it is not fully rigorous

What is the problem with A|B=b being a random variable? (Apart from you unfamiliarity with the concept, I mean.)

Edit: I don’t say there are no problems, I ask what do you think the problem is? There is no problem in the discrete case. In the continuous setting things are indeed more complicated (but if the limiting process is well defined there are no issues).

Note that the same lack of rigour that you find in conditional ramdom variables affects conditional probabilities. If you can accept the latter there is no reason to reject the former.

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