Hi again On Fri, Oct 8, 2010 at 1:13 PM, David Winsemius <dwinsem...@comcast.net> wrote: > > On Oct 8, 2010, at 1:09 PM, Alison Callahan wrote: > >> See below. >> >> On Fri, Oct 8, 2010 at 1:01 PM, David Winsemius <dwinsem...@comcast.net> >> wrote: >>> >>> On Oct 8, 2010, at 12:46 PM, Alison Callahan wrote: >>> >>>> Hello all, >>>> >>>> I am trying to perform an ANOVA on some data in a data frame, but when >>>> I try to use lm(), I get the following error: > > The question that should have been posed was how did you use lm()? > > It could be that the inappropriate use of a factor as a dependent variable > was the cause. Did you use something like: > > lm(island_id ~ refseq_better, data=dfrm) # ?? > My usage of lm() was as follows:
lmout <- lm(refseq_proportion~fiveprime,data=props_df) > Example: >> dfrm <- data.frame(a=factor(rnorm(10)), b=rnorm(10)) >> lm(a ~ b, data=dfrm) > Error in storage.mode(y) <- "double" : > invalid to change the storage mode of a factor > In addition: Warning message: > In model.response(mf, "numeric") : > using type="numeric" with a factor response will be ignored > > >>>> >>>> Error in storage.mode(y) <- "double" : >>>> invalid to change the storage mode of a factor >>>> In addition: Warning message: >>>> In model.response(mf, "numeric") : >>>> using type="numeric" with a factor response will be ignored >>>> >>>> Here is a subset of my data: >>>> >>>> island_id refseq_better total refseq_proportion >>>> fiveprime threeprime island_size >>>> 1a 29 57 0.508771929824561 >>>> 11127 201378 190251 >>>> 1c 27 90 0.3 >>>> 6303879 6600994 297115 >>>> 1d 33 115 0.28695652173913 >>>> 7001283 7421591 420308 >>>> 2b 11 42 0.261904761904762 >>>> 4381375 4520137 138762 >>>> 2d 27 81 0.333333333333333 >>>> 5203929 5497271 293342 >>>> 3a 44 141 0.312056737588652 >>>> 28792 552044 523252 >>>> >>>> When I use sapply(dataframe,mode) to check the modes of the columns, >>>> this is my output: >>>> >>>> island_id refseq_better total >>>> refseq_proportion >>>> "numeric" "numeric" "numeric" "numeric" >>>> fiveprime threeprime island_size >>>> "numeric" "numeric" "numeric" >>> >>> So? >>> >>>> mode(factor(1:10)) >>> >>> [1] "numeric" >>> >>> Storage mode is not the right question. "class" is the correct question. >>> Best would be to try is.factor() >> >> Looking at the error message, the problem does appear to be with >> storage mode ... is this affected by whether the variables are >> factors? Note this part of the error: >> >> Error in storage.mode(y) <- "double" : >> invalid to change the storage mode of a factor >> >>> >>> >>>> How do I need to change the format of my data frame so that I do not >>>> get the above error? >>> >>> Figure out which of your columns are factors and apply the FAQ 7.12 >>> >>> -- >>> David. >>>> >>>> Thanks! >>>> >>>> Alison Callahan >>>> PhD candidate >>> >>> >>> David Winsemius, MD >>> West Hartford, CT >>> >>> >> Thanks, >> >> Alison > > David Winsemius, MD > West Hartford, CT > > ______________________________________________ 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.
