TITLE: Is there a symbol for "dependent"?
QUESTION [5 upvotes]: For random variables $A$ and $B$, $A \perp B$ is sometimes used to denote "A is independent of B".  Is there a symbol that is commonly used to mean "A is not independent of B"?

REPLY [3 votes]: It seems that a crossed ⫫ would do it. In latex code \nBigCI or Unicode U+2aeb. 
Check its use at this nice lecture on causality https://www.youtube.com/watch?v=bHOGP5o3Vu0&t=2941s