Parameters of Distributions 11/3

I spent alot of today's lecture going on about the subteleties of detecting which were the parameters and which were the random value's paricular value that we wanted to compute the pobability at.

The example I did is know as Banach's matchbox problem. A pipe-smoking mathematican has two boxes of matches one in the left pocket, one in the right, what is the probability that when he discovers the right box is empty, there are k matches in the other box?

I showed how to solve this with the Negative Binomial distribution with parameters $(r=N+1,p=\frac{1}{2})$.