Posts Tagged ‘ dependence ’

Copulas and tail dependence, part 3

September 18, 2012
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Copulas and tail dependence, part 3

We have seen extreme value copulas in the section where we did consider general families of copulas. In the bivariate case, an extreme value can be writtenwhere is Pickands dependence function, which is a convex function satisfyingObserve that in ...

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Copulas and tail dependence, part 2

September 18, 2012
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Copulas and tail dependence, part 2

An alternative to describe tail dependence can be found in the Ledford & Tawn (1996) for instance. The intuition behind can be found in Fischer & Klein (2007)). Assume that and have the same distribution. Now, if we assume that those vari...

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Non transitivity of correlation for random vectors in dimension 3

May 18, 2012
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Non transitivity of correlation for random vectors in dimension 3

Dependence in dimension 2 is difficult. But one has to admit that dimension 2 is way more simple than dimension 3 ! I recently rediscovered a nice paper, Langford, Schwertman & Owens (2001), on transitivity of the property of being positively c...

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