Background Story:

Sir Francis Galton, who is the cousin of Charles Darwin was an English Victoria polymath, eugenicist and statistician. He proved the linear combination of normal distribution is still normal distribution and he is also,the inventor of the triangle device – quincunx. Here, we will talk about the research that he has implemented long time ago(1885).

library(UsingR)
data(galton)
par(mfrow=c(1,1))
plot(galton$parent, galton$child, pch=19, col=”blue”)
m <- lm(galton$child ~ galton$parent)
lines(galton$parent, m$fitted, col=”red”, lwd=3)