2. Theory
2.1 Copulas
2.1.1. Concept of Copula and properties of Copulas
Every joint distribution function of random variables contains information about its margins and dependence structure between them. Concept of Copula comes in handy when it is needed to isolate that dependence structure from margins. Copula is a function that links univariate margins and their joint multivariate distributions. Let us consider the properties that a function must satisfy in order to be a copula.