# Probability

Let A be an event, and let IA be the associated indicator random variable ( IA is 1 if A occurs, and zero if A does not occur). Similarly, let IB be the indicator of another event, B . Suppose that P(A)=p , P(B)=q , and P(A∩B)=r.

Find the variance of IA−IB , in terms of p , q , r .

Var(IA−IB)=

1. 👍 2
2. 👎 0
3. 👁 301
1. Var(IA−IB)=p−2r+q−(p−q)^2

1. 👍 0
2. 👎 0

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