Notation question for probability measures on product spaces

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In the context of probability measures on product spaces, a unique probability measure \mu on (A×B, \mathcal A⊗\mathcal B) can be defined based on a probability measure p on (A, \mathcal A) and a measurable function q that assigns probability measures on (B, \mathcal B). The discussion centers around the lack of a standard nomenclature or notation for this measure \mu, with suggestions like pq, p⊗q, q∘p, and q^p being considered but deemed potentially misleading. The original poster ultimately chose the notation \mu_{p,q} for clarity in their work, acknowledging the absence of a widely accepted term. The conversation highlights the need for consistent terminology in the field of probability theory. Further exploration may yield a more established name in the future.
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Let (A,\mathcal A), (B,\mathcal B) be measurable spaces. Let p be a probability measure on (A,\mathcal A), and let q:A\to\mathcal P(B,\mathcal B) be a measurable function which takes each a\in A to some probability measure q(\cdot|a) on (B,\mathcal B). Then there is a unique probability measure \mu on (A\times B, \mathcal A\otimes\mathcal B) which has \mu(\hat A\times \hat B) = \int_{\hat A} q(\hat B|\cdot)\text{ d}p for every \hat A\in\mathcal A, \hat B\in\mathcal B.

The question: Is there a typical thing to call \mu? Does it have a name, in terms of p and q? How about notation? pq? p\otimes q (which would be misleading)? q\circ p? q^p? I looked around and couldn't find anything consistent.
 
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I'm sorry you are not generating any responses at the moment. Is there any additional information you can share with us? Any new findings?
 
No such luck. In the thing I'm writing, I just named it ##\mu_{p,q}## and fully defined it, since I couldn't find a standard name for it. I figured I'll fix it later if I stumble on a good name elsewhere.
 
I was reading documentation about the soundness and completeness of logic formal systems. Consider the following $$\vdash_S \phi$$ where ##S## is the proof-system making part the formal system and ##\phi## is a wff (well formed formula) of the formal language. Note the blank on left of the turnstile symbol ##\vdash_S##, as far as I can tell it actually represents the empty set. So what does it mean ? I guess it actually means ##\phi## is a theorem of the formal system, i.e. there is a...

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