jrflanders
2009-Sep-18 23:49 UTC
[R] Why don't formulas that work for lm() work for plotmeans?
I know that simple line plots showing a point representing the mean + an error bar are difficult in R, but I am clearly missing something. I simply want to show how a the mean and 95% CI of a chemical concentration (y) vary over space (x) under four temperature regimes (T; a categorical factor). plotmeans, in the gplots library, should allow for such a figure, right? After all, it invokes lm() in the help file for the formula, so any formula that works in lm() (e.g., y~x | T) should work in plotmeans. Obviously this is not so - can anyone suggest an alternative command or help me understand how the syntac differs? Thanks... -- View this message in context: http://www.nabble.com/Why-don%27t-formulas-that-work-for-lm%28%29-work-for-plotmeans--tp25517081p25517081.html Sent from the R help mailing list archive at Nabble.com.
Peter Ehlers
2009-Sep-19 13:30 UTC
[R] Why don't formulas that work for lm() work for plotmeans?
Did lm(y ~ x | T) work for you? Let's see a reproducible example. Peter jrflanders wrote:> I know that simple line plots showing a point representing the mean + an > error bar are difficult in R, but I am clearly missing something. I simply > want to show how a the mean and 95% CI of a chemical concentration (y) vary > over space (x) under four temperature regimes (T; a categorical factor). > plotmeans, in the gplots library, should allow for such a figure, right? > After all, it invokes lm() in the help file for the formula, so any formula > that works in lm() (e.g., y~x | T) should work in plotmeans. Obviously this > is not so - can anyone suggest an alternative command or help me understand > how the syntac differs? Thanks...