ABSTRACT
To obtain a quantitative index of the strength of a relationship, the Pearson r statistic would be calculated. The correlation between two variables, X and Y is denoted rXY. An equation for computing r which is an analogue of the correlation formula for Spearman’s correlation shown in Chapter 7 is,
where X and Y are two random quantitative variables. This formula is equivalent to the cross product sums of squares (SSXY) divided by the square root of the sums of squares for X (SSXX) multiplied by the sums of squares for Y (SSYY). This can be written as,
