The behaviour of each of these elements is described by a simple linear relationship between two of the four basic variables describing a circuit: current, voltage, charge and magnetic flux.

Regression refers to a quantitative measure of the relationship between ... two independent variables such as the example discussed above will produce a formula with this basic structure: If ...

Covariance indicates the relationship of two variables whenever ... When graphed on a X/Y axis, covariance between two variables displays visually as both variables mirror similar changes at ...