Rank association is a fundamental tool to express dependence for ordinal data. Measures of rank correlation have been developed in several contexts for more than a century and we were able to cite more than thirty of these coefficients, from simple ones to relatively complicated definitions...

In a less widely known contribution, Béla Martos (1966, Hungarian Academy of Sciences) introduced a generalized notion of concavity that is closely related to what is nowadays known as r-concavity in the operations research literature, and that is identical to what is nowadays known as...