You can use predict() by specifying a complete data.frame() for prediction to
the argument newdata=. Look:
da <- expand.grid(x1=LETTERS[1:4], x2=1:9)
da$y <- rnorm(da$x1)
da$y[sample(length(da$y), 5)] <- NA
m0 <- lm(y~x1+x2, data=da)
predict(m0) # NA not predicted
predict(m0, newdata=da) # NA predicted
Sincerely.
Walmes.
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..(....)... 0ooo... Walmes Zeviani
...\..(.....(.....)... Master in Statistics and Agricultural
Experimentation
....\_)..... )../.... walmeszeviani at hotmail.com, Lavras - MG, Brasil
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