`  ::I agree that there is turbelence and a million other processes involved in the flipping of a real coin, and that it would be quite inconceivable for a computer to simulate all of these processes.  But that's boringly obvious.  Why even mention it?  ::Perhaps ``calculate`` the probability would be a term that communicates my point better?  The probability is a computable number.  These probabilities can be manipulated and composed every which way, without involving random numbers, in what may be called a ``simulation``.  The end result is a discrete probability distribution which is an exact solution, not an outcome or event.  ::However, a computer cannot produce an exact solution if the probability model involves a poission distribution.  ::If the coin is biased and the resulting probability is an uncomputable number, this implies that it was biased by an uncomputable number.  But nondimensionalizing solves this problem.  Essentially, we're not really concerned with ``numbers`` when we're talking about a computer.  We're talking, rather, about finite states.  So long as the problem can be coded by a finite number of states, it is discrete, and can be operated on by a turing machine.  ::The poission distribution is often represented in the form:  :::  ::A special case of the poission distribution is the exponential distribution, where the x parameter is 1:  :::  ::-  `