Data

sales.summer <- rnorm(26, mean=5, sd=1)
drowns.summer <- rnorm(26, mean=5, sd=1)
sales.winter <- rnorm(26, mean=3, sd=1)
drowns.winter <- rnorm(26, mean=3, sd=1)

Scatter Diagram for all

plot(c(sales.winter, sales.summer), c(drowns.winter, drowns.summer), xlim=c(0, 9), ylim=c(0, 9), ann=FALSE)
title(main="청량음료 판매량과 익사자수", xlab="청량음료 판매고", ylab="익사자수")
text(x=2, y=8, labels=paste("r=", round(cor(c(sales.winter, sales.summer), c(drowns.winter, drowns.summer)), digits=2)))

Scatter Diagram in winter

plot(sales.winter, drowns.winter, xlim=c(0, 9), ylim=c(0, 9), col="red")

cor(sales.winter, drowns.winter)
## [1] 0.05668075

Scatter Diagram in winter

plot(sales.winter, drowns.winter, xlim=c(0, 9), ylim=c(0, 9), col="red", ann=FALSE)
points(sales.summer, drowns.summer, col="blue")
title(main="청량음료 판매량과 익사자수", xlab="청량음료 판매고", ylab="익사자수")
text(x=8, y=8, labels=paste("r =", round(cor(sales.winter, drowns.winter), digits=2)))
text(x=1, y=1, labels=paste("r =", round(cor(sales.summer, drowns.summer),2)))

```