Two random variables Law of Iterated Expectations (LIE): E(Y) = E[E(Y | X)] E[E(Y | X)] take the expectation with respect to Y given X take the expectation with respect to X E(X) = E[E(X | Y)] In the discrete case E(X) = ?[E(X | Y = y_i) ? p(Y = y_i)] E(Y) = ?[E(Y | X = x_i) ? p(X = x_i)]
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First, we need to understand the Law of Iterated Expectations (LIE). LIE states that the expectation of a random variable Y can be found by taking the expectation of the conditional expectation of Y given another random variable X. Mathematically, this can be Show more…
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