# Notations: probability

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Hello everyone

In class, we saw some stuff in probability and I wondered if they could also be written with these symbols:

$P(A \; \text{and}\; B)=P(A\cap B)$

$P(A \; \text{or}\; B)=P(A\cup B)$

And so I also wondered if they could also be written with proposition logic symbols

$P(A\wedge B)$ and $P(A\vee B)$

For the chance of 'not A', we saw this notation: $P(\bar{A})$, but I wonder if this: $P(\neg A)$ is also good, and which one is the 'best' (best known, most correct one).

Thanks.

F

Edited by Function
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What we have is a set of potential outcomes of an experiment (the "sample space"), which we'll denote with Ω, and individual outcomes are subsets of the sample space. In addition, we have a function P : Ω → [0,1] assigning a probability to each outcome. So when we say P(AB), we're talking about a union of subsets being assigned a probability. The propositional logic symbols don't entirely make sense in this context.

I suppose you could have a situation where you're randomly generating strings of logical symbols along with the two statements A and B, in which case the string "AB" would be one potential output. But of course, that's not the meaning you're asking about.

Edit: I should note, as always, that notation isn't sacred. You could use P(AB) to denote the probability of two events A and B both happening. But it'd be a little strange.

Edited by John

Thanks

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