[R] BLUP with missing data

Marcio Resende mresendeufv at yahoo.com.br
Wed Sep 23 03:02:08 CEST 2009


hello guys, I need to do a BLUP in the simplest model
y = Xm + Zg + e
however I have missing data in the analysis which I can´t consider as
0(zero). So I need to generate the matrix X'Z, Z'X and Z'Z step by step; I
can´t use 
crossprod(x) #neither
X'X <- t(x)%*%x

because I should skip the elements with missing data in the matrix

I´ll try to be more clear,
supposing
a matrix x and a z
dim (t(x)) = 2275 788
dim (z) = 788 1

but I have in my matrix the effect 0(zero) which is not missing, therefore I
can´t just replace the missing values by 0(zero) and i can´t just remove it
from the matrix because it would unbalance it

A way to do it could be generate Z'X step by step e.g
Z'X [1, 1] is equal the sum of the product between the elements in the first
collumn of X and the first collumn of Z skipping the elements whenever there
is a missing data

However I can´t do this in R

Does anybody know how to do it this way or an easier way to do it?
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