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Fit values for NA's in linear regression

2 messages · Luca Wacker, Spencer Graves

#
Hi,

To obtain estimates for some missing values in my data I fitted a 
linear regression and then used the command fitted(model) to get the 
fitted values from the model, but R doesn't return any values for the 
NA's. I can calculate the fitted values from the estimates obtained 
from the summary of model, but that's not very handy. Is there a way to 
include the missing values in the analysis and get fitted values for 
the NA's? I tried to use with the function na.action, but that didn't 
work.


thanks

Luca
#
Have you considered:

 > set.seed(1)
 > tstDF <- data.frame(x=1:4, y=c(NA, 2:4+rnorm(3)))
 > fit <- lm(y~x, tstDF)
 > predict(fit)
        2        3        4
1.678441 2.573854 3.469266
 > predict(fit, tstDF)
         1         2         3         4
0.7830284 1.6784410 2.5738536 3.4692662

	  spencer graves
Luca Wacker wrote: