In this case, once we add our assumptions that (1) every toss is independent of the other tosses and (2) the probability of W is the same on every toss, probability theory provides a unique answer, known as the binomial distribution. This is the common “coin tossing” distribution. And so the probability of observing w W’s in n tosses, with a probability p of W, is: Pr(w|n, p) = n! w!(n − w)!p w (1 − p) n−w
