## Function Correlation-From-Summaries

(

**correlation-from-summaries** < n > < x > < x2 > < y > < y2 > < xy > )

Computes the correlation of two variables given summary statistics of the

variables. All of these arguments are summed over the variable: ` x' is the sum<br> of the x's, `

x2' is the sum of the squares of the x's, and ` xy' is the sum of<br> the cross-products, which is also known as the inner product of the variables x<br> and y. Of course, `

n' is the number of data values in each variable.