Hello everyone. My task is set certain levels (that is all rows of that level) as missing values in factor B20_A. Excuse the notation, it happens to be a question number in a survey. So I thought it would work easily by defining the levels and their labels using the 'factor' function.
> levels(B20_A) [1] " " "5.6" "No " "Yes" #as you can see 'No' is a level. #I below define the levels, I expect 5.6 and blank to be set as NA B20_A<-factor(B20_A,levels=c('No','Yes'),labels=c('No','Yes')) summary(B20_A) No Yes NA's 0 149 580 to my surprise, 'No' is also set as NA, why is this happening? I am a frequent SPSS user and I am surprised that this operation does not seem to be so straight forward in R. Thanks my object is defined below. structure(c(4L, 1L, 4L, 4L, 1L, 3L, 1L, 3L, 1L, 1L, 1L, 3L, 1L, 3L, 3L, 1L, 1L, 4L, 1L, 4L, 4L, 3L, 1L, 3L, 4L, 3L, 4L, 3L, 3L, 1L, 1L, 3L, 1L, 3L, 4L, 4L, 3L, 1L, 1L, 4L, 4L, 3L, 3L, 3L, 1L, 3L, 3L, 3L, 1L, 4L, 1L, 4L, 1L, 1L, 1L, 3L, 3L, 1L, 4L, 4L, 3L, 1L, 1L, 4L, 4L, 3L, 1L, 1L, 3L, 1L, 4L, 3L, 3L, 3L, 1L, 4L, 3L, 3L, 4L, 4L, 4L, 4L, 1L, 3L, 1L, 1L, 1L, 1L, 3L, 3L, 1L, 3L, 1L, 1L, 1L, 3L, 1L, 1L, 4L, 3L, 1L, 4L, 4L, 4L, 4L, 4L, 3L, 3L, 3L, 3L, 1L, 3L, 3L, 4L, 3L, 1L, 1L, 1L, 1L, 1L, 3L, 3L, 1L, 1L, 1L, 4L, 1L, 3L, 3L, 1L, 3L, 1L, 1L, 1L, 1L, 3L, 3L, 3L, 1L, 1L, 1L, 4L, 4L, 1L, 1L, 1L, 1L, 1L, 3L, 3L, 1L, 1L, 3L, 3L, 4L, 4L, 1L, 1L, 3L, 3L, 1L, 1L, 1L, 3L, 1L, 1L, 1L, 1L, 1L, 4L, 1L, 1L, 4L, 3L, 3L, 1L, 3L, 4L, 3L, 1L, 1L, 3L, 1L, 1L, 1L, 3L, 4L, 1L, 3L, 4L, 1L, 4L, 1L, 4L, 1L, 3L, 1L, 3L, 1L, 4L, 4L, 1L, 1L, 4L, 4L, 4L, 4L, 4L, 4L, 1L, 1L, 1L, 1L, 4L, 3L, 4L, 1L, 3L, 1L, 4L, 4L, 1L, 1L, 1L, 1L, 1L, 1L, 3L, 3L, 1L, 3L, 1L, 1L, 4L, 1L, 1L, 3L, 1L, 1L, 4L, 1L, 1L, 1L, 4L, 1L, 1L, 3L, 1L, 1L, 4L, 3L, 1L, 1L, 4L, 1L, 4L, 1L, 1L, 1L, 3L, 3L, 4L, 1L, 1L, 3L, 1L, 3L, 1L, 1L, 4L, 4L, 1L, 1L, 4L, 4L, 1L, 1L, 3L, 1L, 3L, 3L, 3L, 3L, 1L, 4L, 1L, 1L, 3L, 1L, 1L, 1L, 3L, 3L, 4L, 4L, 1L, 1L, 4L, 4L, 3L, 1L, 3L, 1L, 4L, 1L, 1L, 1L, 1L, 3L, 4L, 2L, 1L, 1L, 1L, 1L, 3L, 4L, 1L, 3L, 1L, 1L, 1L, 3L, 1L, 1L, 1L, 4L, 3L, 1L, 3L, 1L, 4L, 4L, 1L, 1L, 4L, 1L, 1L, 1L, 1L, 1L, 1L, 4L, 1L, 1L, 3L, 3L, 1L, 1L, 4L, 4L, 1L, 3L, 1L, 3L, 1L, 3L, 3L, 1L, 1L, 4L, 1L, 3L, 4L, 1L, 1L, 4L, 3L, 1L, 3L, 1L, 3L, 4L, 1L, 3L, 3L, 3L, 1L, 1L, 1L, 1L, 1L, 3L, 1L, 4L, 3L, 1L, 1L, 1L, 3L, 1L, 4L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 3L, 1L, 4L, 4L, 4L, 1L, 1L, 1L, 4L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 3L, 1L, 3L, 4L, 1L, 1L, 4L, 1L, 4L, 1L, 3L, 1L, 3L, 1L, 3L, 1L, 1L, 1L, 1L, 1L, 4L, 1L, 3L, 4L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 3L, 3L, 4L, 1L, 1L, 3L, 1L, 1L, 1L, 3L, 4L, 1L, 1L, 1L, 3L, 3L, 1L, 1L, 1L, 3L, 4L, 3L, 1L, 4L, 3L, 1L, 1L, 3L, 1L, 1L, 1L, 4L, 1L, 3L, 4L, 4L, 3L, 3L, 1L, 1L, 3L, 1L, 3L, 1L, 1L, 1L, 3L, 1L, 4L, 1L, 1L, 1L, 1L, 4L, 4L, 1L, 1L, 4L, 1L, 4L, 3L, 3L, 1L, 3L, 3L, 1L, 4L, 4L, 1L, 3L, 3L, 4L, 3L, 4L, 3L, 3L, 1L, 3L, 1L, 3L, 4L, 3L, 3L, 3L, 1L, 4L, 3L, 3L, 3L, 1L, 1L, 3L, 4L, 3L, 3L, 1L, 1L, 4L, 3L, 1L, 4L, 1L, 3L, 3L, 1L, 1L, 1L, 3L, 1L, 3L, 3L, 3L, 1L, 1L, 3L, 4L, 1L, 3L, 3L, 1L, 1L, 3L, 3L, 1L, 3L, 1L, 3L, 4L, 1L, 1L, 3L, 1L, 1L, 3L, 3L, 1L, 3L, 4L, 1L, 3L, 3L, 1L, 1L, 3L, 1L, 1L, 3L, 1L, 1L, 4L, 1L, 3L, 1L, 4L, 4L, 3L, 4L, 1L, 1L, 4L, 4L, 4L, 4L, 4L, 3L, 3L, 1L, 1L, 1L, 4L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 4L, 1L, 3L, 3L, 1L, 1L, 3L, 3L, 1L, 4L, 1L, 4L, 1L, 3L, 3L, 1L, 1L, 1L, 1L, 3L, 4L, 3L, 3L, 3L, 4L, 4L, 3L, 4L, 1L, 3L, 1L, 1L, 1L, 1L, 4L, 1L, 4L, 4L, 1L, 3L, 4L, 1L, 1L, 1L, 1L, 3L, 1L, 1L, 1L, 3L, 3L, 1L, 1L, 1L, 1L, 3L, 4L, 1L, 1L, 3L, 3L, 4L, 4L, 1L, 3L, 1L, 4L, 1L, 3L, 1L, 1L, 1L, 1L, 3L, 3L, 1L, 3L, 4L, 1L, 1L, 4L, 3L, 1L, 3L, 1L, 1L, 3L, 1L, 1L, 4L, 1L, 1L, 1L, 4L, 3L, 1L, 3L), .Label = c(" ", "5.6", "No ", "Yes"), class = "factor") Pancho Mulongeni Research Assistant PharmAccess Foundation 1 Fouchè Street Windhoek West Windhoek Namibia Tel: +264 61 419 000 Fax: +264 61 419 001/2 Mob: +264 81 276 6075 ______________________________________________ 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.