used quality control training
creation of frequency distributions. It consists of a rectangular box with an upper chamber containing a large number of beads which are fed into a triangular hopper through a horizontal sliding bar. Beads tumble over several rows of pins which force
the bead to go either left or right
. After a random journey
, beads drop into several vertical slots to create
a frequency distribution
. Invented by the UK scientist Francis Galton in 1890s.