I'm working in R and need to formula to calculate correlation coefficient between x and y. This is without using mean, sd, cor, or lm. So the long form. I tried to work it and it wouldn't process in R.

This is what I tried: sum(length(x)-(mean(x)))(length(x)-mean(y))/sqrt(sum(length(x)-mean(x)^2))sum(length(x)-mean(y)^2)