Coarsening Factors
Murray Jorgensen <maj at waikato.ac.nz> writes:
It is not uncommon to want to coarsen a factor by grouping levels together. I have found one way to do this in R:
> sites
[1] F A A D A A B F C F A D E E D C F A E D F C E D E F F D B C Levels: A B C D E F
> regions <- list(I = c("A","B","C"), II = "D", III = c("E","F"))
> library(Epi)
> region <- Relevel(sites,regions)
> region
[1] III I I II I I I III I III I II III III II I III I III [20] II III I III II III III III II I I Levels: I II III However this seems like using a sledgehammer to crack a nut. Can someone suggest a simpler way to do this task?
Yes,
regions <- list(I = c("A","B","C"), II = "D", III = c("E","F"))
levels(sites) <- regions
sites
[1] III I I II I I I III I III I II III III II I III I III [20] II III I III II III III III II I I Levels: I II III
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