Bean machine
（重定向自Galton board）
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![A working replica of the machine (following a slightly modified design.)](/Images/godic/202501/14/Planche_de_Galton0553.jpg")
The bean machine, also known as the quincunx or Galton box, is a device invented by Sir Francis Galton to demonstrate the central limit theorem, in particular that the normal distribution is approximate to the binomial distribution. Among its applications, it afforded insight into regression to the mean or "regression to mediocrity".