• ## Statistics Tables: Craps for the Normal Distribution

By Eric Nielsen

This series of statistical examples is intended to inform students about the statistics (and how it relates to the psychology) casinos use on table games to make them a more informed consumer. This series is not intended to be a “how to beat the house” or any other sort of get rich quick scheme. If I had a way to beat the house, don’t you think I would be doing it and not giving up the secrets? Overall, it is good to think of casino games as forms of entertainment, and you are encouraged to treat them as such. If you have or know someone who has a gambling problem, please use resources, and reach out to a professional for help.

Often students do not have a concept for the Normal Distribution when it comes to the sampling chapter, and the Galton Board is used to give students the visual reference in the classroom for discrete random variables showing a normal distribution when enough observations are dropped through the board. Unless students are soon to be contestants on The Price Is Right and are faced with Plinko, or NBC’s game show The Wall, they are not likely to encounter the board in their life outside the class. A more accessible way for students to see the normal distribution and understand the importance of sample size is the Craps Table.

The casino game of Craps is simplistic: the act of throwing two dice and summing up the showing faces is the experiment in the game of craps. While using the full casino game with payouts and their corresponding probabilities creates a valued learning activity, this activity focuses only on the act of rolling the dice. To emphasize the previous chapters (discrete random variables categorization and visualization)  the image below shows the number of ways the dice total can occur: