Standard Deviation:

Standard deviation of regression (that means. the measure of the dispersion around the regression line) may be determined as

                    σ = (1/ n - 2)[∑Y ²  - a ∑Y - b ∑ X Y ]^{1/ 2}

Correlation Coefficient

Correlation expresses the degree of relationship among two or more variables. In other words, it expresses how well a linear (or other) equation describes the relationship. The correlation coefficient r is a number between - 1 and + 1 and it is designated as positive if Y increases with increase in X, and negative if Y reduce with increase in X. r = 0 indicates the lack of any relationship among the two variables.