Configurable Galton Board by larry009

Last crawled date: 3 years ago

This is a device for performing statistical experiments.
Here's a video of the operation: http://youtu.be/0tp26ChmDxA
Have fun while learning about combinatorics, Pascal's triangle, probability, and the binomial distribution.
Balls are poured into the funnel and allowed to fall and collide into pegs along their journey. Ideally when a ball hits a peg head-on it has a 1/2 chance of going left or right until it finally falls into one of the bins.
The number of paths to each bin is given by C( N, x ).
N is number of rows of pegs (including the top edge of the bins) and x takes values from 0 to N (say 0 is the leftmost bin and N is the rightmost).
There is a triangle overlay that shows all of these numbers and the number of paths through each intermediate peg. This also happens to be Pascal's triangle. You can lay the overlay right over the pegs but take it off when performing experiments.
This particular Galton board will allow you to adjust N anywhere from 1 to 8 and so you can run experiments with as little as 2 bins or up to 9 bins. This is done by plugging the funnel into the corresponding holes aligned above the triangle of pegs.
Ideally and over the long run the number of balls in each bin will follow the binomial distribution.