The Galton board was invented in 1876 by the Victorian genius Sir Francis Galton and presented an elegant demonstration of how a normal distribution arises from the combination of a large number of random events. It gave Galton key insights into the distribution of human characteristics during his studies on heredity. It also played a pivotal role in his development of statistical theory, concepts that remain fundamental today.
The distribution forms as beads navigate through a forest of pegs, arranged so that each time a bead hits a peg, it has randomly deflected the left or the right with equal likelihood. This means beads can take many different paths before it exits the pattern and rests in one of the bins below.
Looking at the pattern’s middle, you will see many different pathways that take the beads to the middle bins. The further out you go, the fewer pathways there are.
There are so many combinations. So when you have 12 rows of pegs to get to the middle two bins…
