DEFINITION of 'Copula'
A statistical measure that represents a multivariate uniform distribution, which examines the association or dependence between many variables. Although the statistical calculation of a copula was invented in 1957, it was not applied to financial markets and finance until the late '90s.
INVESTOPEDIA EXPLAINS 'Copula'
Copulas are a mathematical tool used in finance to help identify economic capital adequacy, market risk, credit risk and operational risk. Interdependence of returns of two or more assets is usually calculated using the correlation coefficient. However, correlation only works well with normal distributions, while distributions in financial markets are mostly skewed. The copula, therefore, has been applied to areas of finance such as option pricing and portfolio valueatrisk to deal with the skewness.

Skewness
Describe asymmetry from the normal distribution in a set of statistical ... 
Correlation
In the world of finance, a statistical measure of how two securities ... 
Correlation Coefficient
A measure that determines the degree to which two variable's ... 
Credit Risk
The risk of loss of principal or loss of a financial reward stemming ... 
Covariance
A measure of the degree to which returns on two risky assets ... 
Value At Risk  VaR
A statistical technique used to measure and quantify the level ...

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