[R] mean and variance of ratio

[Moshe Olshansky]

Hi Irene,

The result depends on the joint distribution of
x1,x2,y1,y2. The mean (or the variance) not always
exist (if, for example, all of them are independent
and normally distributed).
One possibility to estimate mean and variance is to
use simulation (once you verify that they exist!!!).

Regards,

Moshe.

--- Irene Mantzouni <ima at difres.dk> wrote:

> Hi all!
> 
>  
> 
> I try to estimate a statistic of the form:
> (x1-x2)/(y1-y2), where
> x1,x2,y1,y2 represent variable means, so each has an
> estimate and
> standard error associated with it. 
> 
> How is it possible to estimate the mean and the
> variance of this ratio? 
> 
>  
> 
> Thank you!
> 
> 
> 	[[alternative HTML version deleted]]
> 
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