[R] how to compare a null model with a model with NAs?

[Ronaldo Reis-Jr.]

Hi,

I make a model:

m.null <- glm(y~1)

m.comp <- glm(y~x1+x2+x3)

I try make a anova like this

anova(m.null,m.comp,test="F")

The result:

Erro em anova.glmlist(c(list(object), dotargs), dispersion = dispersion,  : 
    models were not all fitted to the same size of dataset

The problem is that I have some NAs in x1, x2 and x3 and is not teh same row 
fo NAs. How to set is in a null model without I need to remove these rows?

Thansk
Ronaldo
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