Erin Hodgess wrote: > Hi Robert! > > Could you please check > str(data.b) > > and see what you have for porosity? It needs to be a factor > > Thanks, > Erin > > Erin, Yes, porosity is a factor. See output below.
> str(data.b) 'data.frame': 96 obs. of 7 variables: $ system : Factor w/ 6 levels ... $ block : int ... $ position: Factor w/ 3 levels "inrow","interrow",.. $ depth : Factor w/ 2 levels "0-7.5cm","7-5-15cm": ... $ porosity: Factor w/ 2 levels "macro ","micro":... $ x : num 1.41 1.5 1.3 1.53 ... $ y : num 12.10 14.60 23.30 ... Robert >> >> ______________________________________________ >> 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. >> > > > ______________________________________________ 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.