Also have a look at this thread from last week https://stat.ethz.ch/pipermail/r-help/2005-July/074550.html
Regards, Adai On Thu, 2005-07-28 at 18:59 +0200, Petr Pikal wrote: > Hallo > > On 28 Jul 2005 at 18:44, Andreas Cordes wrote: > > > Hi, > > I have a problem that is hopefully easily solvable, but I dont find > > the clue in the documentation. I am examining a linear model. One of > > the variables has NA values. Even though na.action=na.omit, i get NA > > as results for this variable. Can I use lm in such a case to get > > estimates? Or do I have to do some form of imputation before doing so? > > Here is the call and the results, hope you can help. Best regards, > > Andreas > > ---------------------------------------------------------------------- > > ----------------------- lm(formula = ESSIK ~ ALTER + as.factor(S2) + > > as.factor(S15A) + > > as.factor(S8) + as.factor(LAND) + as.factor(S18B) + > > as.factor(BERUF) + as.factor(KIRCHE) + as.factor(H_EINKOM) + > > as.factor(PARTNERS), na.action = na.omit) > > > > Residuals: > > Min 1Q Median 3Q Max > > -17.0675 -2.0151 0.4267 2.7644 9.7333 > > > > Coefficients: (2 not defined because of singularities) > > Problem is not in NA handling but that some of your coeficients > can be represented as linear combination of other coeficients. You > have to omit them. > > HTH > Petr > > > > Estimate Std. Error t value Pr(>|t|) > > (Intercept) 23.755915 1.844110 12.882 < 2e-16 *** > > [...] > > as.factor(BERUF)7 -1.236836 0.701323 -1.764 0.077942 . > > as.factor(KIRCHE)1 -0.811751 0.237699 -3.415 0.000649 *** > > as.factor(H_EINKOM)2 NA NA NA NA > > as.factor(H_EINKOM)3 NA NA NA NA > > as.factor(PARTNERS)1 2.057070 0.342546 6.005 2.23e-09 *** > > > > ______________________________________________ > > [email protected] mailing list > > https://stat.ethz.ch/mailman/listinfo/r-help > > PLEASE do read the posting guide! > > http://www.R-project.org/posting-guide.html > > Petr Pikal > [EMAIL PROTECTED] > > ______________________________________________ > [email protected] mailing list > https://stat.ethz.ch/mailman/listinfo/r-help > PLEASE do read the posting guide! http://www.R-project.org/posting-guide.html > ______________________________________________ [email protected] mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide! http://www.R-project.org/posting-guide.html
