[R-sig-eco] t-test with inverse variance weighting in R

[Manuel Spínola]

Dear list members,

I have 4 estimates (each estimate have its se or variance), 2 from 
treatment units and 2 from control units.  I want to do a t-test with 
inverse variance weighting to compare treatment vs control units.
Does anybody knows if there is an R function to do this type of analysis?
I am trying to get the confidence interval of the difference (I am not 
interested in the t and P values).
Thank you very much in advance.
Best,

Manuel Spínola

-- 
Manuel Spínola, Ph.D.
Instituto Internacional en Conservación y Manejo de Vida Silvestre
Universidad Nacional
Apartado 1350-3000
Heredia
COSTA RICA
mspinola at una.ac.cr
mspinola10 at gmail.com
Teléfono: 277-3598
Fax: 237-7036