6.2 More formally
In the last section, there were initially four different possible outcomes, those being the four kinds of cookies that could pop out of our machine. In this situation, our sample space is the collection
{chocolate, sugar, oatmeal, coconut}.
We also say that these four are the values of a random variable. Random variables usually have names like X and Y.
The sample space for getting one cookie and then another has size 16. A probability distribution assigns a probability to each of the possible outcomes, which are the values of the random variable. The probability distribution for the basic balanced case is
chocolate → 0.25 | sugar → 0.25 | |
oatmeal → 0.25 | coconut → 0.25 . |