Like the Pearson correlation coefficient, the Spearman correlation coefficient
is used to assess the extent to which a variable (x) is correlated with protected
status (y). The Spearman coefficient, however, can detect relationships that the
Pearson coefficient cannot. For example, when comparing the extent to which
a variable like debt-to-income is correlated to protected status, the correlation
may remain low as DTI increases, until it suddenly rises rapidly — a non-linear
relationship that a simple Pearson’s correlation coefficient may not readily capture
but Spearman’s does.
