Question : X and Y are indicator variables for whether or not the events A and B occur, i.e.

$\displaystyle X = \begin{cases} 1 & if \ A \ occur \\ 0 & otherwise \end{cases}$

$\displaystyle Y = \begin{cases} 1 & if \ B \ occur \\ 0 & otherwise \end{cases}$

Compute cov(X,Y) If cov(X,Y)>0, show that P(Y=1|X=1)> P(Y=1)

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$\displaystyle cov(X,Y) = E[(X- \mu_x)(Y - \mu_y)]$......for cov(X,Y)>0 and others