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#1 2013-02-03 08:35:26
- ElGreco
- Guest
[PROBABILITY] Conditional Independence does not imply Independence
Hello everybody, I have a probability question.
Could you please help me prove that "Conditional Independence does not imply Independence", and vice-versa "(Absolute) Independence does not imply Conditional Independence"?
Every book and online resource seems to take it for granted. They only offer simple counter examples, but I haven't found a formal proof, e.g., by contradiction.
If you can reference a book chapter or post the basics of the proof(s) it would help a lot :-)
Thank you for your time!
~ElGreco
#2 2013-02-03 08:39:44
- anonimnystefy
- Real Member
Offline
Re: [PROBABILITY] Conditional Independence does not imply Independence
Hi ElGreco
A counter-example is all you need. If it is not true in one case, it is not true.
And, welcome to the forum! 
Last edited by anonimnystefy (2013-02-03 08:40:08)
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