Suppose that a binary message M ∈ {1,0} is to be communicated from location A to location B via a channel, where M is a Bernoulli random variable with pM(1) = 1 − pM(0) = q. If M = 1 we will transmit the signal X = +2, and if M = 0 we will transmit the signal X = −2. The transmitted signal X, via channel, is corrupted by an additive normal noise W ∼ N(1, 2), so the received signal Y at location B is given by Y = X + W. Assume the receiver decodes the message according to the following rule:
• if Y ≥ 1, then decode the message as M = 1;
• if Y < 1, then decode the message as M = 0.
Find the probability of decoding error. [You can express the answer in terms of the cumulative distribution function of a standard normal random variable Φ(a) = 1/√2π ∫−∞ to a e^(−z^2/2)dz.]