Re: [R] median and joint distribution

2003-07-24 Thread Roger Koenker
For distribution functions F and G we have the (Frechet) bounds: max{0, F(x)+G(y) -1} = H(x,y) = min{F(x),F(y)} where H is the joint df of (X,Y) having marginals F and G. If X and Y are comonotonic (Schmeidler (Econometrica, 1989)), that is if there is a random variable Z, such that X =

RE: [R] median and joint distribution

2003-07-24 Thread Hotz, T.
Dear Salvatore, Assuming that you mean convolution when you write additive linkage, the answer is that there is no general answer. It will depend heavily on the joint distribution of the two random variables. Just to give a simple example, let X~f, Y~g, and P(X=0.4)=P(Y=0.4)=1. Then, X and Y