Georgina Sarah Humphreys <g.humphreys.1 <at> research.gla.ac.uk> writes:
> > Can anyone advise a good transformation for this data below to produce a normalised distribution? > > Many thanks, > Georgina > > Depending on how "normal" you want it to be, this may be impossible because about a third of your data set (14/47) has the same value (1). There's no transformation that can spread out a peak consisting of identical values. d <- c(1,12,1,12,6,17,54,1,12,2,22,27,1,27,1, 1,6,24,10,54,12,5,27,68,1,4,6,27, 1,1,1,1,68,1,7,1,10,5,4,1,7,9,3,19,22,10,4) table(d) > table(d) d 1 2 3 4 5 6 7 9 10 12 17 19 22 24 27 54 68 14 1 1 3 2 3 2 1 3 4 1 1 2 1 4 2 2 Naively, the Box-Cox transformation says you should be using a log transformation (lambda=0) library(MASS) boxcox(d~1) good luck, Ben Bolker ______________________________________________ [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 and provide commented, minimal, self-contained, reproducible code.
