Hello everyone, I feel ashamed to be asking someone to explain such simple notation to me, but I’m having serious problems understanding it. Any help would be deeply appreciated. Thank you.//<![CDATA[ aax_getad_mpb({ "slot_uuid":"f485bc30-20f5-4c34-b261-5f2d6f6142cb" }); //]]>

I’ll use “u” and “n” to denote Union and Intercept as I don’t know how to make the symbols.

What I can understand of the notation is as follow.

If A and B are two events and P(A) = 0.6, P(B) = 0.3 and P(AuB) = 0.8

P(A) would be the probability of event A occurring by itself and

P(B) would be the probability of B occurring by itself.

P(AuB) would be either A or B occurring.

P(AnB) would be when A and B occurs at the same time.

P(A’) when A does not occur, so 1 – P(A)

P(B’) when B does not occur, so 1 – P(B)

Now the confusing part…

P(A’nB) What I can understand from the “n” notation is that it represents events happening at the same time, so this would be when A does not occur at all but B does.

What would P(A’uB), P(AuB’) be ?? I’m very confused now.

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# Probability notation

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