Empirical correlation for fuzzy data
For classical two-dimensional data (xi, yi) ∈ 2, i = 1(1)n the empirical correlation coefficient r is defined by
For r the following holds:
a. −1 ≤ r ≤ 1.
b. |r| = 1 if and only if all points (xi, yi) are on a line in the (x, y)-plane.