In the physical version of the Galton board there are balls falling on pins that are in rows. The first row has only one pin, and each subsequent row has one more pin. Each ball falls to the right or to the left. In normal conditions the probability of falling to the right is a half. The Galton board is really a binomial probability experiment. Each ball falls on n pins, always with a probability p of falling to the right. The random variable X is the number of times a ball falls to the right. X is binomially distributed with parameters n and p. The box where the ball ends up shows the number of times the ball fell to the right. Using several balls means that you have a repeated binomial experiment, so the result is an approximation of the binomial distribution.
In the computer simulation you can define the properties of the Galton board: the number of rows, the probability of falling to the right, and the number of balls. The result of the simulation can be compared with the theoretical result which is presented in yellow. This can be done in a table or a bar chart (vertical line graph).
Settings and buttons
You choose the number of rows in the grid, the probability of each ball falling to the right, and the number of balls going through the grid.
View
With Count you see the results in the form of a table.
With Graph you see the results in the form of a bar chart (vertical line graph).
With Theory you also see the theoretical distribution.
Tempo bar
With the tempo bar you can change the speed of the simulation before and during the simulation.
With Step you can track the experiment step by step.
Fast is designed to enable you to create lots of data.
Interrupt/continue
With the space bar you can interrupt or resume the simulation.
With the print button you obtain a complete preview, and you have the options to copy the complete tree to the clipboard, send it to Word, or print it immediately.