Hi It would be better if you provided either str(yourdata) or dput(yourdata)
(or a part illustrating those 2 kinds of missing values) Anyway I would use NA for missing and some other identifier for empty. temp a b c 1 1 empty 2 NA filled xx 3 2 filled xx is.na(temp) a b c [1,] FALSE FALSE FALSE [2,] TRUE FALSE FALSE [3,] FALSE FALSE FALSE dput(temp) structure(list(a = c(1L, NA, 2L), b = structure(c(1L, 2L, 2L), .Label = c("empty", "filled"), class = "factor"), c = structure(c(1L, 2L, 2L), .Label = c("", "xx"), class = "factor")), .Names = c("a", "b", "c"), class = "data.frame", row.names = c(NA, -3L)) str(temp) 'data.frame': 3 obs. of 3 variables: $ a: int 1 NA 2 $ b: Factor w/ 2 levels "empty","filled": 1 2 2 $ c: Factor w/ 2 levels "","xx": 1 2 2 The only real NA value which can be used for imputation is in first column. Regards Petr > -----Original Message----- > From: r-help-boun...@r-project.org [mailto:r-help-bounces@r- > project.org] On Behalf Of Ma Teresa Martinez Soriano > Sent: Friday, July 19, 2013 11:28 AM > To: r-help@R-project.org > Subject: [R] R Help > > Hi > everyone, > > I have > a dataset which I am handling with > R . Unfortunately I have two kinds of empty cells, one corresponds to > missing values and the other one is empty because it has to. > > I 'm going > to put an example (just a part of my dataset ) to try to clarify my > question: > > missing > values are represented withNAs > > > Enterprise > Data of Stablishment Earnings > 2005 earning > 2006 earnings 2007 earning 2008 > > Enterprise > 1 > 05/06/2007 > It has to be empty It has to be > empty > 2,3 > NA > > Enterprise > 2 > 09/08/2005 > 2.3 > 3,6 > NA > 1.6 > > > > My intention is to find this missing values using imputation (library > VIM) . How could I differenciate this NA with Cells that have to be > empty?? I have tried putting Na for missing values and Nan for the > others but it doesn't work because R imputes everythitng. > Could you answer me > to this e-mail > > Thanks in > advance > > > [[alternative HTML version deleted]] ______________________________________________ R-help@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.